Subroutine */ int igraphdnapps_(integer *n, integer *kev, integer *np,
doublereal *shiftr, doublereal *shifti, doublereal *v, integer *ldv,
doublereal *h__, integer *ldh, doublereal *resid, doublereal *q,
integer *ldq, doublereal *workl, doublereal *workd)
{
/* Initialized data */
IGRAPH_F77_SAVE logical first = TRUE_;
/* System generated locals */
integer h_dim1, h_offset, v_dim1, v_offset, q_dim1, q_offset, i__1, i__2,
i__3, i__4;
doublereal d__1, d__2;
/* Local variables */
doublereal c__, f, g;
integer i__, j;
doublereal r__, s, t, u[3];
real t0, t1;
doublereal h11, h12, h21, h22, h32;
integer jj, ir, nr;
doublereal tau;
IGRAPH_F77_SAVE doublereal ulp;
doublereal tst1;
integer iend;
IGRAPH_F77_SAVE doublereal unfl, ovfl;
extern /* Subroutine */ int igraphdscal_(integer *, doublereal *, doublereal *,
integer *), igraphdlarf_(char *, integer *, integer *, doublereal *,
integer *, doublereal *, doublereal *, integer *, doublereal *);
logical cconj;
extern /* Subroutine */ int igraphdgemv_(char *, integer *, integer *,
doublereal *, doublereal *, integer *, doublereal *, integer *,
doublereal *, doublereal *, integer *), igraphdcopy_(integer *,
doublereal *, integer *, doublereal *, integer *), igraphdaxpy_(integer
*, doublereal *, doublereal *, integer *, doublereal *, integer *)
, igraphdmout_(integer *, integer *, integer *, doublereal *, integer *,
integer *, char *, ftnlen), igraphdvout_(integer *, integer *,
doublereal *, integer *, char *, ftnlen), igraphivout_(integer *,
integer *, integer *, integer *, char *, ftnlen);
extern doublereal igraphdlapy2_(doublereal *, doublereal *);
extern /* Subroutine */ int igraphdlabad_(doublereal *, doublereal *);
extern doublereal igraphdlamch_(char *);
extern /* Subroutine */ int igraphdlarfg_(integer *, doublereal *, doublereal *,
integer *, doublereal *);
doublereal sigmai;
extern doublereal igraphdlanhs_(char *, integer *, doublereal *, integer *,
doublereal *);
extern /* Subroutine */ int igraphsecond_(real *), igraphdlacpy_(char *, integer *,
integer *, doublereal *, integer *, doublereal *, integer *), igraphdlaset_(char *, integer *, integer *, doublereal *,
doublereal *, doublereal *, integer *), igraphdlartg_(
doublereal *, doublereal *, doublereal *, doublereal *,
doublereal *);
integer logfil, ndigit;
doublereal sigmar;
integer mnapps = 0, msglvl;
real tnapps = 0.;
integer istart;
IGRAPH_F77_SAVE doublereal smlnum;
integer kplusp;
/* %----------------------------------------------------%
| Include files for debugging and timing information |
%----------------------------------------------------%
%------------------%
| Scalar Arguments |
%------------------%
%-----------------%
| Array Arguments |
%-----------------%
%------------%
| Parameters |
%------------%
%------------------------%
| Local Scalars & Arrays |
%------------------------%
%----------------------%
| External Subroutines |
%----------------------%
%--------------------%
| External Functions |
%--------------------%
%----------------------%
| Intrinsics Functions |
%----------------------%
%----------------%
| Data statments |
%----------------%
Parameter adjustments */
--workd;
--resid;
--workl;
--shifti;
--shiftr;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
h_dim1 = *ldh;
h_offset = 1 + h_dim1;
h__ -= h_offset;
q_dim1 = *ldq;
q_offset = 1 + q_dim1;
q -= q_offset;
/* Function Body
%-----------------------%
| Executable Statements |
%-----------------------% */
if (first) {
/* %-----------------------------------------------%
| Set machine-dependent constants for the |
| stopping criterion. If norm(H) <= sqrt(OVFL), |
| overflow should not occur. |
| REFERENCE: LAPACK subroutine dlahqr |
%-----------------------------------------------% */
unfl = igraphdlamch_("safe minimum");
ovfl = 1. / unfl;
igraphdlabad_(&unfl, &ovfl);
ulp = igraphdlamch_("precision");
smlnum = unfl * (*n / ulp);
first = FALSE_;
}
/* %-------------------------------%
| Initialize timing statistics |
| & message level for debugging |
%-------------------------------% */
igraphsecond_(&t0);
msglvl = mnapps;
kplusp = *kev + *np;
/* %--------------------------------------------%
| Initialize Q to the identity to accumulate |
| the rotations and reflections |
%--------------------------------------------% */
igraphdlaset_("All", &kplusp, &kplusp, &c_b5, &c_b6, &q[q_offset], ldq);
/* %----------------------------------------------%
| Quick return if there are no shifts to apply |
%----------------------------------------------% */
if (*np == 0) {
goto L9000;
}
/* %----------------------------------------------%
| Chase the bulge with the application of each |
| implicit shift. Each shift is applied to the |
| whole matrix including each block. |
%----------------------------------------------% */
cconj = FALSE_;
i__1 = *np;
for (jj = 1; jj <= i__1; ++jj) {
sigmar = shiftr[jj];
sigmai = shifti[jj];
if (msglvl > 2) {
igraphivout_(&logfil, &c__1, &jj, &ndigit, "_napps: shift number.", (
ftnlen)21);
igraphdvout_(&logfil, &c__1, &sigmar, &ndigit, "_napps: The real part "
"of the shift ", (ftnlen)35);
igraphdvout_(&logfil, &c__1, &sigmai, &ndigit, "_napps: The imaginary "
"part of the shift ", (ftnlen)40);
}
/* %-------------------------------------------------%
| The following set of conditionals is necessary |
| in order that complex conjugate pairs of shifts |
| are applied together or not at all. |
%-------------------------------------------------% */
if (cconj) {
/* %-----------------------------------------%
| cconj = .true. means the previous shift |
| had non-zero imaginary part. |
%-----------------------------------------% */
cconj = FALSE_;
goto L110;
} else if (jj < *np && abs(sigmai) > 0.) {
/* %------------------------------------%
| Start of a complex conjugate pair. |
%------------------------------------% */
cconj = TRUE_;
} else if (jj == *np && abs(sigmai) > 0.) {
/* %----------------------------------------------%
| The last shift has a nonzero imaginary part. |
| Don't apply it; thus the order of the |
| compressed H is order KEV+1 since only np-1 |
| were applied. |
%----------------------------------------------% */
++(*kev);
goto L110;
}
istart = 1;
L20:
/* %--------------------------------------------------%
| if sigmai = 0 then |
| Apply the jj-th shift ... |
| else |
| Apply the jj-th and (jj+1)-th together ... |
| (Note that jj < np at this point in the code) |
| end |
| to the current block of H. The next do loop |
| determines the current block ; |
%--------------------------------------------------% */
i__2 = kplusp - 1;
for (i__ = istart; i__ <= i__2; ++i__) {
/* %----------------------------------------%
| Check for splitting and deflation. Use |
| a standard test as in the QR algorithm |
| REFERENCE: LAPACK subroutine dlahqr |
%----------------------------------------% */
tst1 = (d__1 = h__[i__ + i__ * h_dim1], abs(d__1)) + (d__2 = h__[
i__ + 1 + (i__ + 1) * h_dim1], abs(d__2));
if (tst1 == 0.) {
i__3 = kplusp - jj + 1;
tst1 = igraphdlanhs_("1", &i__3, &h__[h_offset], ldh, &workl[1]);
}
/* Computing MAX */
d__2 = ulp * tst1;
if ((d__1 = h__[i__ + 1 + i__ * h_dim1], abs(d__1)) <= max(d__2,
smlnum)) {
if (msglvl > 0) {
igraphivout_(&logfil, &c__1, &i__, &ndigit, "_napps: matrix sp"
"litting at row/column no.", (ftnlen)42);
igraphivout_(&logfil, &c__1, &jj, &ndigit, "_napps: matrix spl"
"itting with shift number.", (ftnlen)43);
igraphdvout_(&logfil, &c__1, &h__[i__ + 1 + i__ * h_dim1], &
ndigit, "_napps: off diagonal element.", (ftnlen)
29);
}
iend = i__;
h__[i__ + 1 + i__ * h_dim1] = 0.;
goto L40;
}
/* L30: */
}
iend = kplusp;
L40:
if (msglvl > 2) {
igraphivout_(&logfil, &c__1, &istart, &ndigit, "_napps: Start of curre"
"nt block ", (ftnlen)31);
igraphivout_(&logfil, &c__1, &iend, &ndigit, "_napps: End of current b"
"lock ", (ftnlen)29);
}
/* %------------------------------------------------%
| No reason to apply a shift to block of order 1 |
%------------------------------------------------% */
if (istart == iend) {
goto L100;
}
/* %------------------------------------------------------%
| If istart + 1 = iend then no reason to apply a |
| complex conjugate pair of shifts on a 2 by 2 matrix. |
%------------------------------------------------------% */
if (istart + 1 == iend && abs(sigmai) > 0.) {
goto L100;
}
h11 = h__[istart + istart * h_dim1];
h21 = h__[istart + 1 + istart * h_dim1];
if (abs(sigmai) <= 0.) {
/* %---------------------------------------------%
| Real-valued shift ==> apply single shift QR |
%---------------------------------------------% */
f = h11 - sigmar;
g = h21;
i__2 = iend - 1;
for (i__ = istart; i__ <= i__2; ++i__) {
/* %-----------------------------------------------------%
| Contruct the plane rotation G to zero out the bulge |
%-----------------------------------------------------% */
igraphdlartg_(&f, &g, &c__, &s, &r__);
if (i__ > istart) {
/* %-------------------------------------------%
| The following ensures that h(1:iend-1,1), |
| the first iend-2 off diagonal of elements |
| H, remain non negative. |
%-------------------------------------------% */
if (r__ < 0.) {
r__ = -r__;
c__ = -c__;
s = -s;
}
h__[i__ + (i__ - 1) * h_dim1] = r__;
h__[i__ + 1 + (i__ - 1) * h_dim1] = 0.;
}
/* %---------------------------------------------%
| Apply rotation to the left of H; H <- G'*H |
%---------------------------------------------% */
i__3 = kplusp;
for (j = i__; j <= i__3; ++j) {
t = c__ * h__[i__ + j * h_dim1] + s * h__[i__ + 1 + j *
h_dim1];
h__[i__ + 1 + j * h_dim1] = -s * h__[i__ + j * h_dim1] +
c__ * h__[i__ + 1 + j * h_dim1];
h__[i__ + j * h_dim1] = t;
/* L50: */
}
/* %---------------------------------------------%
| Apply rotation to the right of H; H <- H*G |
%---------------------------------------------%
Computing MIN */
i__4 = i__ + 2;
i__3 = min(i__4,iend);
for (j = 1; j <= i__3; ++j) {
t = c__ * h__[j + i__ * h_dim1] + s * h__[j + (i__ + 1) *
h_dim1];
h__[j + (i__ + 1) * h_dim1] = -s * h__[j + i__ * h_dim1]
+ c__ * h__[j + (i__ + 1) * h_dim1];
h__[j + i__ * h_dim1] = t;
/* L60: */
}
/* %----------------------------------------------------%
| Accumulate the rotation in the matrix Q; Q <- Q*G |
%----------------------------------------------------%
Computing MIN */
i__4 = j + jj;
i__3 = min(i__4,kplusp);
for (j = 1; j <= i__3; ++j) {
t = c__ * q[j + i__ * q_dim1] + s * q[j + (i__ + 1) *
q_dim1];
q[j + (i__ + 1) * q_dim1] = -s * q[j + i__ * q_dim1] +
c__ * q[j + (i__ + 1) * q_dim1];
q[j + i__ * q_dim1] = t;
/* L70: */
}
/* %---------------------------%
| Prepare for next rotation |
%---------------------------% */
if (i__ < iend - 1) {
f = h__[i__ + 1 + i__ * h_dim1];
g = h__[i__ + 2 + i__ * h_dim1];
}
/* L80: */
}
/* %-----------------------------------%
| Finished applying the real shift. |
%-----------------------------------% */
} else {
/* %----------------------------------------------------%
| Complex conjugate shifts ==> apply double shift QR |
%----------------------------------------------------% */
h12 = h__[istart + (istart + 1) * h_dim1];
h22 = h__[istart + 1 + (istart + 1) * h_dim1];
h32 = h__[istart + 2 + (istart + 1) * h_dim1];
/* %---------------------------------------------------------%
| Compute 1st column of (H - shift*I)*(H - conj(shift)*I) |
%---------------------------------------------------------% */
s = sigmar * 2.f;
t = igraphdlapy2_(&sigmar, &sigmai);
u[0] = (h11 * (h11 - s) + t * t) / h21 + h12;
u[1] = h11 + h22 - s;
u[2] = h32;
i__2 = iend - 1;
for (i__ = istart; i__ <= i__2; ++i__) {
/* Computing MIN */
i__3 = 3, i__4 = iend - i__ + 1;
nr = min(i__3,i__4);
/* %-----------------------------------------------------%
| Construct Householder reflector G to zero out u(1). |
| G is of the form I - tau*( 1 u )' * ( 1 u' ). |
%-----------------------------------------------------% */
igraphdlarfg_(&nr, u, &u[1], &c__1, &tau);
if (i__ > istart) {
h__[i__ + (i__ - 1) * h_dim1] = u[0];
h__[i__ + 1 + (i__ - 1) * h_dim1] = 0.;
if (i__ < iend - 1) {
h__[i__ + 2 + (i__ - 1) * h_dim1] = 0.;
}
}
u[0] = 1.;
/* %--------------------------------------%
| Apply the reflector to the left of H |
%--------------------------------------% */
i__3 = kplusp - i__ + 1;
igraphdlarf_("Left", &nr, &i__3, u, &c__1, &tau, &h__[i__ + i__ *
h_dim1], ldh, &workl[1]);
/* %---------------------------------------%
| Apply the reflector to the right of H |
%---------------------------------------%
Computing MIN */
i__3 = i__ + 3;
ir = min(i__3,iend);
igraphdlarf_("Right", &ir, &nr, u, &c__1, &tau, &h__[i__ * h_dim1 +
1], ldh, &workl[1]);
/* %-----------------------------------------------------%
| Accumulate the reflector in the matrix Q; Q <- Q*G |
%-----------------------------------------------------% */
igraphdlarf_("Right", &kplusp, &nr, u, &c__1, &tau, &q[i__ * q_dim1
+ 1], ldq, &workl[1]);
/* %----------------------------%
| Prepare for next reflector |
%----------------------------% */
if (i__ < iend - 1) {
u[0] = h__[i__ + 1 + i__ * h_dim1];
u[1] = h__[i__ + 2 + i__ * h_dim1];
if (i__ < iend - 2) {
u[2] = h__[i__ + 3 + i__ * h_dim1];
}
}
/* L90: */
}
/* %--------------------------------------------%
| Finished applying a complex pair of shifts |
| to the current block |
%--------------------------------------------% */
}
L100:
/* %---------------------------------------------------------%
| Apply the same shift to the next block if there is any. |
%---------------------------------------------------------% */
istart = iend + 1;
if (iend < kplusp) {
goto L20;
}
/* %---------------------------------------------%
| Loop back to the top to get the next shift. |
%---------------------------------------------% */
L110:
;
}
/* %--------------------------------------------------%
| Perform a similarity transformation that makes |
| sure that H will have non negative sub diagonals |
%--------------------------------------------------% */
i__1 = *kev;
for (j = 1; j <= i__1; ++j) {
if (h__[j + 1 + j * h_dim1] < 0.) {
i__2 = kplusp - j + 1;
igraphdscal_(&i__2, &c_b43, &h__[j + 1 + j * h_dim1], ldh);
/* Computing MIN */
i__3 = j + 2;
i__2 = min(i__3,kplusp);
igraphdscal_(&i__2, &c_b43, &h__[(j + 1) * h_dim1 + 1], &c__1);
/* Computing MIN */
i__3 = j + *np + 1;
i__2 = min(i__3,kplusp);
igraphdscal_(&i__2, &c_b43, &q[(j + 1) * q_dim1 + 1], &c__1);
}
/* L120: */
}
i__1 = *kev;
for (i__ = 1; i__ <= i__1; ++i__) {
/* %--------------------------------------------%
| Final check for splitting and deflation. |
| Use a standard test as in the QR algorithm |
| REFERENCE: LAPACK subroutine dlahqr |
%--------------------------------------------% */
tst1 = (d__1 = h__[i__ + i__ * h_dim1], abs(d__1)) + (d__2 = h__[i__
+ 1 + (i__ + 1) * h_dim1], abs(d__2));
if (tst1 == 0.) {
tst1 = igraphdlanhs_("1", kev, &h__[h_offset], ldh, &workl[1]);
}
/* Computing MAX */
d__1 = ulp * tst1;
if (h__[i__ + 1 + i__ * h_dim1] <= max(d__1,smlnum)) {
h__[i__ + 1 + i__ * h_dim1] = 0.;
}
/* L130: */
}
/* %-------------------------------------------------%
| Compute the (kev+1)-st column of (V*Q) and |
| temporarily store the result in WORKD(N+1:2*N). |
| This is needed in the residual update since we |
| cannot GUARANTEE that the corresponding entry |
| of H would be zero as in exact arithmetic. |
%-------------------------------------------------% */
if (h__[*kev + 1 + *kev * h_dim1] > 0.) {
igraphdgemv_("N", n, &kplusp, &c_b6, &v[v_offset], ldv, &q[(*kev + 1) *
q_dim1 + 1], &c__1, &c_b5, &workd[*n + 1], &c__1);
}
/* %----------------------------------------------------------%
| Compute column 1 to kev of (V*Q) in backward order |
| taking advantage of the upper Hessenberg structure of Q. |
%----------------------------------------------------------% */
i__1 = *kev;
for (i__ = 1; i__ <= i__1; ++i__) {
i__2 = kplusp - i__ + 1;
igraphdgemv_("N", n, &i__2, &c_b6, &v[v_offset], ldv, &q[(*kev - i__ + 1) *
q_dim1 + 1], &c__1, &c_b5, &workd[1], &c__1);
igraphdcopy_(n, &workd[1], &c__1, &v[(kplusp - i__ + 1) * v_dim1 + 1], &
c__1);
/* L140: */
}
/* %-------------------------------------------------%
| Move v(:,kplusp-kev+1:kplusp) into v(:,1:kev). |
%-------------------------------------------------% */
igraphdlacpy_("A", n, kev, &v[(kplusp - *kev + 1) * v_dim1 + 1], ldv, &v[
v_offset], ldv);
/* %--------------------------------------------------------------%
| Copy the (kev+1)-st column of (V*Q) in the appropriate place |
%--------------------------------------------------------------% */
if (h__[*kev + 1 + *kev * h_dim1] > 0.) {
igraphdcopy_(n, &workd[*n + 1], &c__1, &v[(*kev + 1) * v_dim1 + 1], &c__1);
}
/* %-------------------------------------%
| Update the residual vector: |
| r <- sigmak*r + betak*v(:,kev+1) |
| where |
| sigmak = (e_{kplusp}'*Q)*e_{kev} |
| betak = e_{kev+1}'*H*e_{kev} |
%-------------------------------------% */
igraphdscal_(n, &q[kplusp + *kev * q_dim1], &resid[1], &c__1);
if (h__[*kev + 1 + *kev * h_dim1] > 0.) {
igraphdaxpy_(n, &h__[*kev + 1 + *kev * h_dim1], &v[(*kev + 1) * v_dim1 + 1],
&c__1, &resid[1], &c__1);
}
if (msglvl > 1) {
igraphdvout_(&logfil, &c__1, &q[kplusp + *kev * q_dim1], &ndigit, "_napps:"
" sigmak = (e_{kev+p}^T*Q)*e_{kev}", (ftnlen)40);
igraphdvout_(&logfil, &c__1, &h__[*kev + 1 + *kev * h_dim1], &ndigit, "_na"
"pps: betak = e_{kev+1}^T*H*e_{kev}", (ftnlen)37);
igraphivout_(&logfil, &c__1, kev, &ndigit, "_napps: Order of the final Hes"
"senberg matrix ", (ftnlen)45);
if (msglvl > 2) {
igraphdmout_(&logfil, kev, kev, &h__[h_offset], ldh, &ndigit, "_napps:"
" updated Hessenberg matrix H for next iteration", (ftnlen)
54);
}
}
L9000:
igraphsecond_(&t1);
tnapps += t1 - t0;
return 0;
/* %---------------%
| End of dnapps |
%---------------% */
} /* igraphdnapps_ */
Subroutine */ int igraphdnaupd_(integer *ido, char *bmat, integer *n, char *
which, integer *nev, doublereal *tol, doublereal *resid, integer *ncv,
doublereal *v, integer *ldv, integer *iparam, integer *ipntr,
doublereal *workd, doublereal *workl, integer *lworkl, integer *info)
{
/* Format strings */
static char fmt_1000[] = "(//,5x,\002==================================="
"==========\002,/5x,\002= Nonsymmetric implicit Arnoldi update co"
"de =\002,/5x,\002= Version Number: \002,\002 2.4\002,21x,\002 "
"=\002,/5x,\002= Version Date: \002,\002 07/31/96\002,16x,\002 ="
"\002,/5x,\002=============================================\002,/"
"5x,\002= Summary of timing statistics =\002,/5x,"
"\002=============================================\002,//)";
static char fmt_1100[] = "(5x,\002Total number update iterations "
" = \002,i5,/5x,\002Total number of OP*x operations "
" = \002,i5,/5x,\002Total number of B*x operations = "
"\002,i5,/5x,\002Total number of reorthogonalization steps = "
"\002,i5,/5x,\002Total number of iterative refinement steps = "
"\002,i5,/5x,\002Total number of restart steps = "
"\002,i5,/5x,\002Total time in user OP*x operation = "
"\002,f12.6,/5x,\002Total time in user B*x operation ="
" \002,f12.6,/5x,\002Total time in Arnoldi update routine = "
"\002,f12.6,/5x,\002Total time in naup2 routine ="
" \002,f12.6,/5x,\002Total time in basic Arnoldi iteration loop = "
"\002,f12.6,/5x,\002Total time in reorthogonalization phase ="
" \002,f12.6,/5x,\002Total time in (re)start vector generation = "
"\002,f12.6,/5x,\002Total time in Hessenberg eig. subproblem ="
" \002,f12.6,/5x,\002Total time in getting the shifts = "
"\002,f12.6,/5x,\002Total time in applying the shifts ="
" \002,f12.6,/5x,\002Total time in convergence testing = "
"\002,f12.6,/5x,\002Total time in computing final Ritz vectors ="
" \002,f12.6/)";
/* System generated locals */
integer v_dim1, v_offset, i__1, i__2;
/* Builtin functions */
integer s_cmp(char *, char *, ftnlen, ftnlen), s_wsfe(cilist *), e_wsfe(
void), do_fio(integer *, char *, ftnlen);
/* Local variables */
integer j;
real t0, t1;
IGRAPH_F77_SAVE integer nb, ih, iq, np, iw, ldh, ldq;
integer nbx = 0;
IGRAPH_F77_SAVE integer nev0, mode;
integer ierr;
IGRAPH_F77_SAVE integer iupd, next;
integer nopx = 0;
IGRAPH_F77_SAVE integer levec;
real trvec, tmvbx;
IGRAPH_F77_SAVE integer ritzi;
extern /* Subroutine */ int igraphdvout_(integer *, integer *, doublereal *,
integer *, char *, ftnlen), igraphivout_(integer *, integer *, integer *
, integer *, char *, ftnlen);
IGRAPH_F77_SAVE integer ritzr;
extern /* Subroutine */ int igraphdnaup2_(integer *, char *, integer *, char *,
integer *, integer *, doublereal *, doublereal *, integer *,
integer *, integer *, integer *, doublereal *, integer *,
doublereal *, integer *, doublereal *, doublereal *, doublereal *,
doublereal *, integer *, doublereal *, integer *, doublereal *,
integer *);
real tnaup2, tgetv0;
extern doublereal igraphdlamch_(char *);
extern /* Subroutine */ int igraphsecond_(real *);
integer logfil, ndigit;
real tneigh;
integer mnaupd = 0;
IGRAPH_F77_SAVE integer ishift;
integer nitref;
IGRAPH_F77_SAVE integer bounds;
real tnaupd;
extern /* Subroutine */ int igraphdstatn_(void);
real titref, tnaitr;
IGRAPH_F77_SAVE integer msglvl;
real tngets, tnapps, tnconv;
IGRAPH_F77_SAVE integer mxiter;
integer nrorth = 0, nrstrt = 0;
real tmvopx;
/* Fortran I/O blocks */
static cilist io___30 = { 0, 6, 0, fmt_1000, 0 };
static cilist io___31 = { 0, 6, 0, fmt_1100, 0 };
/* %----------------------------------------------------%
| Include files for debugging and timing information |
%----------------------------------------------------%
%------------------%
| Scalar Arguments |
%------------------%
%-----------------%
| Array Arguments |
%-----------------%
%------------%
| Parameters |
%------------%
%---------------%
| Local Scalars |
%---------------%
%----------------------%
| External Subroutines |
%----------------------%
%--------------------%
| External Functions |
%--------------------%
%-----------------------%
| Executable Statements |
%-----------------------%
Parameter adjustments */
--workd;
--resid;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
--iparam;
--ipntr;
--workl;
/* Function Body */
if (*ido == 0) {
/* %-------------------------------%
| Initialize timing statistics |
| & message level for debugging |
%-------------------------------% */
igraphdstatn_();
igraphsecond_(&t0);
msglvl = mnaupd;
/* %----------------%
| Error checking |
%----------------% */
ierr = 0;
ishift = iparam[1];
levec = iparam[2];
mxiter = iparam[3];
nb = iparam[4];
/* %--------------------------------------------%
| Revision 2 performs only implicit restart. |
%--------------------------------------------% */
iupd = 1;
mode = iparam[7];
if (*n <= 0) {
ierr = -1;
} else if (*nev <= 0) {
ierr = -2;
} else if (*ncv <= *nev + 1 || *ncv > *n) {
ierr = -3;
} else if (mxiter <= 0) {
ierr = -4;
} else if (s_cmp(which, "LM", (ftnlen)2, (ftnlen)2) != 0 && s_cmp(
which, "SM", (ftnlen)2, (ftnlen)2) != 0 && s_cmp(which, "LR",
(ftnlen)2, (ftnlen)2) != 0 && s_cmp(which, "SR", (ftnlen)2, (
ftnlen)2) != 0 && s_cmp(which, "LI", (ftnlen)2, (ftnlen)2) !=
0 && s_cmp(which, "SI", (ftnlen)2, (ftnlen)2) != 0) {
ierr = -5;
} else if (*(unsigned char *)bmat != 'I' && *(unsigned char *)bmat !=
'G') {
ierr = -6;
} else /* if(complicated condition) */ {
/* Computing 2nd power */
i__1 = *ncv;
if (*lworkl < i__1 * i__1 * 3 + *ncv * 6) {
ierr = -7;
} else if (mode < 1 || mode > 5) {
ierr = -10;
} else if (mode == 1 && *(unsigned char *)bmat == 'G') {
ierr = -11;
} else if (ishift < 0 || ishift > 1) {
ierr = -12;
}
}
/* %------------%
| Error Exit |
%------------% */
if (ierr != 0) {
*info = ierr;
*ido = 99;
goto L9000;
}
/* %------------------------%
| Set default parameters |
%------------------------% */
if (nb <= 0) {
nb = 1;
}
if (*tol <= 0.) {
*tol = igraphdlamch_("EpsMach");
}
/* %----------------------------------------------%
| NP is the number of additional steps to |
| extend the length NEV Lanczos factorization. |
| NEV0 is the local variable designating the |
| size of the invariant subspace desired. |
%----------------------------------------------% */
np = *ncv - *nev;
nev0 = *nev;
/* %-----------------------------%
| Zero out internal workspace |
%-----------------------------%
Computing 2nd power */
i__2 = *ncv;
i__1 = i__2 * i__2 * 3 + *ncv * 6;
for (j = 1; j <= i__1; ++j) {
workl[j] = 0.;
/* L10: */
}
/* %-------------------------------------------------------------%
| Pointer into WORKL for address of H, RITZ, BOUNDS, Q |
| etc... and the remaining workspace. |
| Also update pointer to be used on output. |
| Memory is laid out as follows: |
| workl(1:ncv*ncv) := generated Hessenberg matrix |
| workl(ncv*ncv+1:ncv*ncv+2*ncv) := real and imaginary |
| parts of ritz values |
| workl(ncv*ncv+2*ncv+1:ncv*ncv+3*ncv) := error bounds |
| workl(ncv*ncv+3*ncv+1:2*ncv*ncv+3*ncv) := rotation matrix Q |
| workl(2*ncv*ncv+3*ncv+1:3*ncv*ncv+6*ncv) := workspace |
| The final workspace is needed by subroutine dneigh called |
| by dnaup2. Subroutine dneigh calls LAPACK routines for |
| calculating eigenvalues and the last row of the eigenvector |
| matrix. |
%-------------------------------------------------------------% */
ldh = *ncv;
ldq = *ncv;
ih = 1;
ritzr = ih + ldh * *ncv;
ritzi = ritzr + *ncv;
bounds = ritzi + *ncv;
iq = bounds + *ncv;
iw = iq + ldq * *ncv;
/* Computing 2nd power */
i__1 = *ncv;
next = iw + i__1 * i__1 + *ncv * 3;
ipntr[4] = next;
ipntr[5] = ih;
ipntr[6] = ritzr;
ipntr[7] = ritzi;
ipntr[8] = bounds;
ipntr[14] = iw;
}
/* %-------------------------------------------------------%
| Carry out the Implicitly restarted Arnoldi Iteration. |
%-------------------------------------------------------% */
igraphdnaup2_(ido, bmat, n, which, &nev0, &np, tol, &resid[1], &mode, &iupd, &
ishift, &mxiter, &v[v_offset], ldv, &workl[ih], &ldh, &workl[
ritzr], &workl[ritzi], &workl[bounds], &workl[iq], &ldq, &workl[
iw], &ipntr[1], &workd[1], info);
/* %--------------------------------------------------%
| ido .ne. 99 implies use of reverse communication |
| to compute operations involving OP or shifts. |
%--------------------------------------------------% */
if (*ido == 3) {
iparam[8] = np;
}
if (*ido != 99) {
goto L9000;
}
iparam[3] = mxiter;
iparam[5] = np;
iparam[9] = nopx;
iparam[10] = nbx;
iparam[11] = nrorth;
/* %------------------------------------%
| Exit if there was an informational |
| error within dnaup2. |
%------------------------------------% */
if (*info < 0) {
goto L9000;
}
if (*info == 2) {
*info = 3;
}
if (msglvl > 0) {
igraphivout_(&logfil, &c__1, &mxiter, &ndigit, "_naupd: Number of update i"
"terations taken", (ftnlen)41);
igraphivout_(&logfil, &c__1, &np, &ndigit, "_naupd: Number of wanted \"con"
"verged\" Ritz values", (ftnlen)48);
igraphdvout_(&logfil, &np, &workl[ritzr], &ndigit, "_naupd: Real part of t"
"he final Ritz values", (ftnlen)42);
igraphdvout_(&logfil, &np, &workl[ritzi], &ndigit, "_naupd: Imaginary part"
" of the final Ritz values", (ftnlen)47);
igraphdvout_(&logfil, &np, &workl[bounds], &ndigit, "_naupd: Associated Ri"
"tz estimates", (ftnlen)33);
}
igraphsecond_(&t1);
tnaupd = t1 - t0;
if (msglvl > 0) {
/* %--------------------------------------------------------%
| Version Number & Version Date are defined in version.h |
%--------------------------------------------------------% */
s_wsfe(&io___30);
e_wsfe();
s_wsfe(&io___31);
do_fio(&c__1, (char *)&mxiter, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nopx, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nbx, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nrorth, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nitref, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nrstrt, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&tmvopx, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tmvbx, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tnaupd, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tnaup2, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tnaitr, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&titref, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tgetv0, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tneigh, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tngets, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tnapps, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tnconv, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&trvec, (ftnlen)sizeof(real));
e_wsfe();
}
L9000:
return 0;
/* %---------------%
| End of dnaupd |
%---------------% */
} /* igraphdnaupd_ */
Subroutine */ int igraphdsgets_(integer *ishift, char *which, integer *kev,
integer *np, doublereal *ritz, doublereal *bounds, doublereal *shifts)
{
/* System generated locals */
integer i__1;
/* Builtin functions */
integer s_cmp(char *, char *, ftnlen, ftnlen);
/* Local variables */
real t0, t1;
integer kevd2;
extern /* Subroutine */ int igraphdswap_(integer *, doublereal *, integer *,
doublereal *, integer *), igraphdcopy_(integer *, doublereal *, integer
*, doublereal *, integer *), igraphdvout_(integer *, integer *,
doublereal *, integer *, char *, ftnlen), igraphivout_(integer *,
integer *, integer *, integer *, char *, ftnlen), igraphsecond_(real *);
integer logfil=0, ndigit, msgets=0, msglvl;
real tsgets;
extern /* Subroutine */ int igraphdsortr_(char *, logical *, integer *,
doublereal *, doublereal *);
/* %----------------------------------------------------%
| Include files for debugging and timing information |
%----------------------------------------------------%
%------------------%
| Scalar Arguments |
%------------------%
%-----------------%
| Array Arguments |
%-----------------%
%------------%
| Parameters |
%------------%
%---------------%
| Local Scalars |
%---------------%
%----------------------%
| External Subroutines |
%----------------------%
%---------------------%
| Intrinsic Functions |
%---------------------%
%-----------------------%
| Executable Statements |
%-----------------------%
%-------------------------------%
| Initialize timing statistics |
| & message level for debugging |
%-------------------------------%
Parameter adjustments */
--shifts;
--bounds;
--ritz;
/* Function Body */
igraphsecond_(&t0);
msglvl = msgets;
if (s_cmp(which, "BE", (ftnlen)2, (ftnlen)2) == 0) {
/* %-----------------------------------------------------%
| Both ends of the spectrum are requested. |
| Sort the eigenvalues into algebraically increasing |
| order first then swap high end of the spectrum next |
| to low end in appropriate locations. |
| NOTE: when np < floor(kev/2) be careful not to swap |
| overlapping locations. |
%-----------------------------------------------------% */
i__1 = *kev + *np;
igraphdsortr_("LA", &c_true, &i__1, &ritz[1], &bounds[1]);
kevd2 = *kev / 2;
if (*kev > 1) {
i__1 = min(kevd2,*np);
igraphdswap_(&i__1, &ritz[1], &c__1, &ritz[max(kevd2,*np) + 1], &c__1);
i__1 = min(kevd2,*np);
igraphdswap_(&i__1, &bounds[1], &c__1, &bounds[max(kevd2,*np) + 1], &
c__1);
}
} else {
/* %----------------------------------------------------%
| LM, SM, LA, SA case. |
| Sort the eigenvalues of H into the desired order |
| and apply the resulting order to BOUNDS. |
| The eigenvalues are sorted so that the wanted part |
| are always in the last KEV locations. |
%----------------------------------------------------% */
i__1 = *kev + *np;
igraphdsortr_(which, &c_true, &i__1, &ritz[1], &bounds[1]);
}
if (*ishift == 1 && *np > 0) {
/* %-------------------------------------------------------%
| Sort the unwanted Ritz values used as shifts so that |
| the ones with largest Ritz estimates are first. |
| This will tend to minimize the effects of the |
| forward instability of the iteration when the shifts |
| are applied in subroutine dsapps. |
%-------------------------------------------------------% */
igraphdsortr_("SM", &c_true, np, &bounds[1], &ritz[1]);
igraphdcopy_(np, &ritz[1], &c__1, &shifts[1], &c__1);
}
igraphsecond_(&t1);
tsgets += t1 - t0;
if (msglvl > 0) {
igraphivout_(&logfil, &c__1, kev, &ndigit, "_sgets: KEV is", (ftnlen)14);
igraphivout_(&logfil, &c__1, np, &ndigit, "_sgets: NP is", (ftnlen)13);
i__1 = *kev + *np;
igraphdvout_(&logfil, &i__1, &ritz[1], &ndigit, "_sgets: Eigenvalues of cu"
"rrent H matrix", (ftnlen)39);
i__1 = *kev + *np;
igraphdvout_(&logfil, &i__1, &bounds[1], &ndigit, "_sgets: Associated Ritz"
" estimates", (ftnlen)33);
}
return 0;
/* %---------------%
| End of dsgets |
%---------------% */
} /* igraphdsgets_ */
/* ----------------------------------------------------------------------- */
/* Subroutine */ int igraphdneupd_(logical *rvec, char *howmny, logical *select,
doublereal *dr, doublereal *di, doublereal *z__, integer *ldz,
doublereal *sigmar, doublereal *sigmai, doublereal *workev, char *
bmat, integer *n, char *which, integer *nev, doublereal *tol,
doublereal *resid, integer *ncv, doublereal *v, integer *ldv, integer
*iparam, integer *ipntr, doublereal *workd, doublereal *workl,
integer *lworkl, integer *info)
{
/* System generated locals */
integer v_dim1, v_offset, z_dim1, z_offset, i__1;
doublereal d__1, d__2;
/* Builtin functions */
double igraphpow_dd(doublereal *, doublereal *);
integer igraphs_cmp(char *, char *, ftnlen, ftnlen);
/* Subroutine */ int igraphs_copy(char *, char *, ftnlen, ftnlen);
/* Local variables */
static integer j, k, ih, jj, np;
static doublereal vl[1] /* was [1][1] */;
static integer ibd, ldh, ldq, iri;
static doublereal sep;
static integer irr, wri, wrr;
extern /* Subroutine */ int igraphdger_(integer *, integer *, doublereal *,
doublereal *, integer *, doublereal *, integer *, doublereal *,
integer *);
static integer mode;
static doublereal eps23;
static integer ierr;
static doublereal temp;
static integer iwev;
static char type__[6];
extern doublereal igraphdnrm2_(integer *, doublereal *, integer *);
static doublereal temp1;
extern /* Subroutine */ int igraphdscal_(integer *, doublereal *, doublereal *,
integer *);
static integer ihbds, iconj;
extern /* Subroutine */ int igraphdgemv_(char *, integer *, integer *,
doublereal *, doublereal *, integer *, doublereal *, integer *,
doublereal *, doublereal *, integer *);
static doublereal conds;
static logical reord;
extern /* Subroutine */ int igraphdcopy_(integer *, doublereal *, integer *,
doublereal *, integer *);
static integer nconv;
extern /* Subroutine */ int igraphdtrmm_(char *, char *, char *, char *,
integer *, integer *, doublereal *, doublereal *, integer *,
doublereal *, integer *), igraphdmout_(
integer *, integer *, integer *, doublereal *, integer *, integer
*, char *);
static integer iwork[1];
static doublereal rnorm;
static integer ritzi;
extern /* Subroutine */ int igraphdvout_(integer *, integer *, doublereal *,
integer *, char *), igraphivout_(integer *, integer *, integer *
, integer *, char *);
static integer ritzr;
extern /* Subroutine */ int igraphdgeqr2_(integer *, integer *, doublereal *,
integer *, doublereal *, doublereal *, integer *);
extern doublereal igraphdlapy2_(doublereal *, doublereal *);
extern /* Subroutine */ int igraphdorm2r_(char *, char *, integer *, integer *,
integer *, doublereal *, integer *, doublereal *, doublereal *,
integer *, doublereal *, integer *);
extern doublereal igraphdlamch_(char *);
static integer iheigi, iheigr, bounds, invsub, iuptri, msglvl, outncv,
ishift, numcnv;
extern /* Subroutine */ int igraphdlacpy_(char *, integer *, integer *,
doublereal *, integer *, doublereal *, integer *),
igraphdlahqr_(logical *, logical *, integer *, integer *, integer *,
doublereal *, integer *, doublereal *, doublereal *, integer *,
integer *, doublereal *, integer *, integer *), igraphdlaset_(char *,
integer *, integer *, doublereal *, doublereal *, doublereal *,
integer *), igraphdtrevc_(char *, char *, logical *, integer *,
doublereal *, integer *, doublereal *, integer *, doublereal *,
integer *, integer *, integer *, doublereal *, integer *
), igraphdtrsen_(char *, char *, logical *, integer *, doublereal
*, integer *, doublereal *, integer *, doublereal *, doublereal *,
integer *, doublereal *, doublereal *, doublereal *, integer *,
integer *, integer *, integer *), igraphdngets_(integer
*, char *, integer *, integer *, doublereal *, doublereal *,
doublereal *, doublereal *, doublereal *);
/* %----------------------------------------------------% */
/* | Include files for debugging and timing information | */
/* %----------------------------------------------------% */
/* \SCCS Information: @(#) */
/* FILE: debug.h SID: 2.3 DATE OF SID: 11/16/95 RELEASE: 2 */
/* %---------------------------------% */
/* | See debug.doc for documentation | */
/* %---------------------------------% */
/* %------------------% */
/* | Scalar Arguments | */
/* %------------------% */
/* %--------------------------------% */
/* | See stat.doc for documentation | */
/* %--------------------------------% */
/* \SCCS Information: @(#) */
/* FILE: stat.h SID: 2.2 DATE OF SID: 11/16/95 RELEASE: 2 */
/* %-----------------% */
/* | Array Arguments | */
/* %-----------------% */
/* %------------% */
/* | Parameters | */
/* %------------% */
/* %---------------% */
/* | Local Scalars | */
/* %---------------% */
/* %----------------------% */
/* | External Subroutines | */
/* %----------------------% */
/* %--------------------% */
/* | External Functions | */
/* %--------------------% */
/* %---------------------% */
/* | Intrinsic Functions | */
/* %---------------------% */
/* %-----------------------% */
/* | Executable Statements | */
/* %-----------------------% */
/* %------------------------% */
/* | Set default parameters | */
/* %------------------------% */
/* Parameter adjustments */
z_dim1 = *ldz;
z_offset = 1 + z_dim1;
z__ -= z_offset;
--workd;
--resid;
--di;
--dr;
--workev;
--select;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
--iparam;
--ipntr;
--workl;
/* Function Body */
msglvl = debug_1.mneupd;
mode = iparam[7];
nconv = iparam[5];
*info = 0;
/* %---------------------------------% */
/* | Get machine dependent constant. | */
/* %---------------------------------% */
eps23 = igraphdlamch_("Epsilon-Machine");
eps23 = igraphpow_dd(&eps23, &c_b3);
/* %--------------% */
/* | Quick return | */
/* %--------------% */
ierr = 0;
if (nconv <= 0) {
ierr = -14;
} else if (*n <= 0) {
ierr = -1;
} else if (*nev <= 0) {
ierr = -2;
} else if (*ncv <= *nev + 1 || *ncv > *n) {
ierr = -3;
} else if (igraphs_cmp(which, "LM", (ftnlen)2, (ftnlen)2) != 0 && igraphs_cmp(which,
"SM", (ftnlen)2, (ftnlen)2) != 0 && igraphs_cmp(which, "LR", (ftnlen)2, (ftnlen)2
) != 0 && igraphs_cmp(which, "SR", (ftnlen)2, (ftnlen)2) != 0
&& igraphs_cmp(which, "LI", (ftnlen)2, (ftnlen)2) != 0 && igraphs_cmp(which,
"SI", (ftnlen)2, (ftnlen)2) != 0) {
ierr = -5;
} else if (*(unsigned char *)bmat != 'I' && *(unsigned char *)bmat != 'G')
{
ierr = -6;
} else /* if(complicated condition) */ {
/* Computing 2nd power */
i__1 = *ncv;
if (*lworkl < i__1 * i__1 * 3 + *ncv * 6) {
ierr = -7;
} else if (*(unsigned char *)howmny != 'A' && *(unsigned char *)
howmny != 'P' && *(unsigned char *)howmny != 'S' && *rvec) {
ierr = -13;
} else if (*(unsigned char *)howmny == 'S') {
ierr = -12;
}
}
if (mode == 1 || mode == 2) {
igraphs_copy(type__, "REGULR", (ftnlen)6, (ftnlen)6);
} else if (mode == 3 && *sigmai == 0.) {
igraphs_copy(type__, "SHIFTI", (ftnlen)6, (ftnlen)6);
} else if (mode == 3) {
igraphs_copy(type__, "REALPT", (ftnlen)6, (ftnlen)6);
} else if (mode == 4) {
igraphs_copy(type__, "IMAGPT", (ftnlen)6, (ftnlen)6);
} else {
ierr = -10;
}
if (mode == 1 && *(unsigned char *)bmat == 'G') {
ierr = -11;
}
/* %------------% */
/* | Error Exit | */
/* %------------% */
if (ierr != 0) {
*info = ierr;
goto L9000;
}
/* %--------------------------------------------------------% */
/* | Pointer into WORKL for address of H, RITZ, BOUNDS, Q | */
/* | etc... and the remaining workspace. | */
/* | Also update pointer to be used on output. | */
/* | Memory is laid out as follows: | */
/* | workl(1:ncv*ncv) := generated Hessenberg matrix | */
/* | workl(ncv*ncv+1:ncv*ncv+2*ncv) := real and imaginary | */
/* | parts of ritz values | */
/* | workl(ncv*ncv+2*ncv+1:ncv*ncv+3*ncv) := error bounds | */
/* %--------------------------------------------------------% */
/* %-----------------------------------------------------------% */
/* | The following is used and set by DNEUPD . | */
/* | workl(ncv*ncv+3*ncv+1:ncv*ncv+4*ncv) := The untransformed | */
/* | real part of the Ritz values. | */
/* | workl(ncv*ncv+4*ncv+1:ncv*ncv+5*ncv) := The untransformed | */
/* | imaginary part of the Ritz values. | */
/* | workl(ncv*ncv+5*ncv+1:ncv*ncv+6*ncv) := The untransformed | */
/* | error bounds of the Ritz values | */
/* | workl(ncv*ncv+6*ncv+1:2*ncv*ncv+6*ncv) := Holds the upper | */
/* | quasi-triangular matrix for H | */
/* | workl(2*ncv*ncv+6*ncv+1: 3*ncv*ncv+6*ncv) := Holds the | */
/* | associated matrix representation of the invariant | */
/* | subspace for H. | */
/* | GRAND total of NCV * ( 3 * NCV + 6 ) locations. | */
/* %-----------------------------------------------------------% */
ih = ipntr[5];
ritzr = ipntr[6];
ritzi = ipntr[7];
bounds = ipntr[8];
ldh = *ncv;
ldq = *ncv;
iheigr = bounds + ldh;
iheigi = iheigr + ldh;
ihbds = iheigi + ldh;
iuptri = ihbds + ldh;
invsub = iuptri + ldh * *ncv;
ipntr[9] = iheigr;
ipntr[10] = iheigi;
ipntr[11] = ihbds;
ipntr[12] = iuptri;
ipntr[13] = invsub;
wrr = 1;
wri = *ncv + 1;
iwev = wri + *ncv;
/* %-----------------------------------------% */
/* | irr points to the REAL part of the Ritz | */
/* | values computed by _neigh before | */
/* | exiting _naup2. | */
/* | iri points to the IMAGINARY part of the | */
/* | Ritz values computed by _neigh | */
/* | before exiting _naup2. | */
/* | ibd points to the Ritz estimates | */
/* | computed by _neigh before exiting | */
/* | _naup2. | */
/* %-----------------------------------------% */
irr = ipntr[14] + *ncv * *ncv;
iri = irr + *ncv;
ibd = iri + *ncv;
/* %------------------------------------% */
/* | RNORM is B-norm of the RESID(1:N). | */
/* %------------------------------------% */
rnorm = workl[ih + 2];
workl[ih + 2] = 0.;
if (msglvl > 2) {
igraphdvout_(&debug_1.logfil, ncv, &workl[irr], &debug_1.ndigit, "_neupd: "
"Real part of Ritz values passed in from _NAUPD.");
igraphdvout_(&debug_1.logfil, ncv, &workl[iri], &debug_1.ndigit, "_neupd: "
"Imag part of Ritz values passed in from _NAUPD.");
igraphdvout_(&debug_1.logfil, ncv, &workl[ibd], &debug_1.ndigit, "_neupd: "
"Ritz estimates passed in from _NAUPD.");
}
if (*rvec) {
reord = FALSE_;
/* %---------------------------------------------------% */
/* | Use the temporary bounds array to store indices | */
/* | These will be used to mark the select array later | */
/* %---------------------------------------------------% */
i__1 = *ncv;
for (j = 1; j <= i__1; ++j) {
workl[bounds + j - 1] = (doublereal) j;
select[j] = FALSE_;
/* L10: */
}
/* %-------------------------------------% */
/* | Select the wanted Ritz values. | */
/* | Sort the Ritz values so that the | */
/* | wanted ones appear at the tailing | */
/* | NEV positions of workl(irr) and | */
/* | workl(iri). Move the corresponding | */
/* | error estimates in workl(bound) | */
/* | accordingly. | */
/* %-------------------------------------% */
np = *ncv - *nev;
ishift = 0;
igraphdngets_(&ishift, which, nev, &np, &workl[irr], &workl[iri], &workl[
bounds], &workl[1], &workl[np + 1]);
if (msglvl > 2) {
igraphdvout_(&debug_1.logfil, ncv, &workl[irr], &debug_1.ndigit, "_neu"
"pd: Real part of Ritz values after calling _NGETS.");
igraphdvout_(&debug_1.logfil, ncv, &workl[iri], &debug_1.ndigit, "_neu"
"pd: Imag part of Ritz values after calling _NGETS.");
igraphdvout_(&debug_1.logfil, ncv, &workl[bounds], &debug_1.ndigit,
"_neupd: Ritz value indices after calling _NGETS.");
}
/* %-----------------------------------------------------% */
/* | Record indices of the converged wanted Ritz values | */
/* | Mark the select array for possible reordering | */
/* %-----------------------------------------------------% */
numcnv = 0;
i__1 = *ncv;
for (j = 1; j <= i__1; ++j) {
/* Computing MAX */
d__1 = eps23, d__2 = igraphdlapy2_(&workl[irr + *ncv - j], &workl[iri +
*ncv - j]);
temp1 = max(d__1,d__2);
jj = (integer) workl[bounds + *ncv - j];
if (numcnv < nconv && workl[ibd + jj - 1] <= *tol * temp1) {
select[jj] = TRUE_;
++numcnv;
if (jj > *nev) {
reord = TRUE_;
}
}
/* L11: */
}
/* %-----------------------------------------------------------% */
/* | Check the count (numcnv) of converged Ritz values with | */
/* | the number (nconv) reported by igraphdnaupd. If these two | */
/* | are different then there has probably been an error | */
/* | caused by incorrect passing of the igraphdnaupd data. | */
/* %-----------------------------------------------------------% */
if (msglvl > 2) {
igraphivout_(&debug_1.logfil, &c__1, &numcnv, &debug_1.ndigit, "_neupd"
": Number of specified eigenvalues");
igraphivout_(&debug_1.logfil, &c__1, &nconv, &debug_1.ndigit, "_neupd:"
" Number of \"converged\" eigenvalues");
}
if (numcnv != nconv) {
*info = -15;
goto L9000;
}
/* %-----------------------------------------------------------% */
/* | Call LAPACK routine dlahqr to compute the real Schur form | */
/* | of the upper Hessenberg matrix returned by DNAUPD . | */
/* | Make a copy of the upper Hessenberg matrix. | */
/* | Initialize the Schur vector matrix Q to the identity. | */
/* %-----------------------------------------------------------% */
i__1 = ldh * *ncv;
igraphdcopy_(&i__1, &workl[ih], &c__1, &workl[iuptri], &c__1);
igraphdlaset_("All", ncv, ncv, &c_b37, &c_b38, &workl[invsub], &ldq);
igraphdlahqr_(&c_true, &c_true, ncv, &c__1, ncv, &workl[iuptri], &ldh, &
workl[iheigr], &workl[iheigi], &c__1, ncv, &workl[invsub], &
ldq, &ierr);
igraphdcopy_(ncv, &workl[invsub + *ncv - 1], &ldq, &workl[ihbds], &c__1);
if (ierr != 0) {
*info = -8;
goto L9000;
}
if (msglvl > 1) {
igraphdvout_(&debug_1.logfil, ncv, &workl[iheigr], &debug_1.ndigit,
"_neupd: Real part of the eigenvalues of H");
igraphdvout_(&debug_1.logfil, ncv, &workl[iheigi], &debug_1.ndigit,
"_neupd: Imaginary part of the Eigenvalues of H");
igraphdvout_(&debug_1.logfil, ncv, &workl[ihbds], &debug_1.ndigit,
"_neupd: Last row of the Schur vector matrix");
if (msglvl > 3) {
igraphdmout_(&debug_1.logfil, ncv, ncv, &workl[iuptri], &ldh, &
debug_1.ndigit, "_neupd: The upper quasi-triangular "
"matrix ");
}
}
if (reord) {
/* %-----------------------------------------------------% */
/* | Reorder the computed upper quasi-triangular matrix. | */
/* %-----------------------------------------------------% */
igraphdtrsen_("None", "V", &select[1], ncv, &workl[iuptri], &ldh, &
workl[invsub], &ldq, &workl[iheigr], &workl[iheigi], &
nconv, &conds, &sep, &workl[ihbds], ncv, iwork, &c__1, &
ierr);
if (ierr == 1) {
*info = 1;
goto L9000;
}
if (msglvl > 2) {
igraphdvout_(&debug_1.logfil, ncv, &workl[iheigr], &debug_1.ndigit,
"_neupd: Real part of the eigenvalues of H--reordered");
igraphdvout_(&debug_1.logfil, ncv, &workl[iheigi], &debug_1.ndigit,
"_neupd: Imag part of the eigenvalues of H--reordered");
if (msglvl > 3) {
igraphdmout_(&debug_1.logfil, ncv, ncv, &workl[iuptri], &ldq, &
debug_1.ndigit, "_neupd: Quasi-triangular matrix"
" after re-ordering");
}
}
}
/* %---------------------------------------% */
/* | Copy the last row of the Schur vector | */
/* | into workl(ihbds). This will be used | */
/* | to compute the Ritz estimates of | */
/* | converged Ritz values. | */
/* %---------------------------------------% */
igraphdcopy_(ncv, &workl[invsub + *ncv - 1], &ldq, &workl[ihbds], &c__1);
/* %----------------------------------------------------% */
/* | Place the computed eigenvalues of H into DR and DI | */
/* | if a spectral transformation was not used. | */
/* %----------------------------------------------------% */
if (igraphs_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) == 0) {
igraphdcopy_(&nconv, &workl[iheigr], &c__1, &dr[1], &c__1);
igraphdcopy_(&nconv, &workl[iheigi], &c__1, &di[1], &c__1);
}
/* %----------------------------------------------------------% */
/* | Compute the QR factorization of the matrix representing | */
/* | the wanted invariant subspace located in the first NCONV | */
/* | columns of workl(invsub,ldq). | */
/* %----------------------------------------------------------% */
igraphdgeqr2_(ncv, &nconv, &workl[invsub], &ldq, &workev[1], &workev[*ncv +
1], &ierr);
/* %---------------------------------------------------------% */
/* | * Postmultiply V by Q using dorm2r . | */
/* | * Copy the first NCONV columns of VQ into Z. | */
/* | * Postmultiply Z by R. | */
/* | The N by NCONV matrix Z is now a matrix representation | */
/* | of the approximate invariant subspace associated with | */
/* | the Ritz values in workl(iheigr) and workl(iheigi) | */
/* | The first NCONV columns of V are now approximate Schur | */
/* | vectors associated with the real upper quasi-triangular | */
/* | matrix of order NCONV in workl(iuptri) | */
/* %---------------------------------------------------------% */
igraphdorm2r_("Right", "Notranspose", n, ncv, &nconv, &workl[invsub], &ldq,
&workev[1], &v[v_offset], ldv, &workd[*n + 1], &ierr);
igraphdlacpy_("All", n, &nconv, &v[v_offset], ldv, &z__[z_offset], ldz);
i__1 = nconv;
for (j = 1; j <= i__1; ++j) {
/* %---------------------------------------------------% */
/* | Perform both a column and row scaling if the | */
/* | diagonal element of workl(invsub,ldq) is negative | */
/* | I'm lazy and don't take advantage of the upper | */
/* | quasi-triangular form of workl(iuptri,ldq) | */
/* | Note that since Q is orthogonal, R is a diagonal | */
/* | matrix consisting of plus or minus ones | */
/* %---------------------------------------------------% */
if (workl[invsub + (j - 1) * ldq + j - 1] < 0.) {
igraphdscal_(&nconv, &c_b64, &workl[iuptri + j - 1], &ldq);
igraphdscal_(&nconv, &c_b64, &workl[iuptri + (j - 1) * ldq], &c__1);
}
/* L20: */
}
if (*(unsigned char *)howmny == 'A') {
/* %--------------------------------------------% */
/* | Compute the NCONV wanted eigenvectors of T | */
/* | located in workl(iuptri,ldq). | */
/* %--------------------------------------------% */
i__1 = *ncv;
for (j = 1; j <= i__1; ++j) {
if (j <= nconv) {
select[j] = TRUE_;
} else {
select[j] = FALSE_;
}
/* L30: */
}
igraphdtrevc_("Right", "Select", &select[1], ncv, &workl[iuptri], &ldq,
vl, &c__1, &workl[invsub], &ldq, ncv, &outncv, &workev[1],
&ierr);
if (ierr != 0) {
*info = -9;
goto L9000;
}
/* %------------------------------------------------% */
/* | Scale the returning eigenvectors so that their | */
/* | Euclidean norms are all one. LAPACK subroutine | */
/* | igraphdtrevc returns each eigenvector normalized so | */
/* | that the element of largest magnitude has | */
/* | magnitude 1; | */
/* %------------------------------------------------% */
iconj = 0;
i__1 = nconv;
for (j = 1; j <= i__1; ++j) {
if (workl[iheigi + j - 1] == 0.) {
/* %----------------------% */
/* | real eigenvalue case | */
/* %----------------------% */
temp = igraphdnrm2_(ncv, &workl[invsub + (j - 1) * ldq], &c__1);
d__1 = 1. / temp;
igraphdscal_(ncv, &d__1, &workl[invsub + (j - 1) * ldq], &c__1);
} else {
/* %-------------------------------------------% */
/* | Complex conjugate pair case. Note that | */
/* | since the real and imaginary part of | */
/* | the eigenvector are stored in consecutive | */
/* | columns, we further normalize by the | */
/* | square root of two. | */
/* %-------------------------------------------% */
if (iconj == 0) {
d__1 = igraphdnrm2_(ncv, &workl[invsub + (j - 1) * ldq], &
c__1);
d__2 = igraphdnrm2_(ncv, &workl[invsub + j * ldq], &c__1);
temp = igraphdlapy2_(&d__1, &d__2);
d__1 = 1. / temp;
igraphdscal_(ncv, &d__1, &workl[invsub + (j - 1) * ldq], &
c__1);
d__1 = 1. / temp;
igraphdscal_(ncv, &d__1, &workl[invsub + j * ldq], &c__1);
iconj = 1;
} else {
iconj = 0;
}
}
/* L40: */
}
igraphdgemv_("T", ncv, &nconv, &c_b38, &workl[invsub], &ldq, &workl[
ihbds], &c__1, &c_b37, &workev[1], &c__1);
iconj = 0;
i__1 = nconv;
for (j = 1; j <= i__1; ++j) {
if (workl[iheigi + j - 1] != 0.) {
/* %-------------------------------------------% */
/* | Complex conjugate pair case. Note that | */
/* | since the real and imaginary part of | */
/* | the eigenvector are stored in consecutive | */
/* %-------------------------------------------% */
if (iconj == 0) {
workev[j] = igraphdlapy2_(&workev[j], &workev[j + 1]);
workev[j + 1] = workev[j];
iconj = 1;
} else {
iconj = 0;
}
}
/* L45: */
}
if (msglvl > 2) {
igraphdcopy_(ncv, &workl[invsub + *ncv - 1], &ldq, &workl[ihbds], &
c__1);
igraphdvout_(&debug_1.logfil, ncv, &workl[ihbds], &debug_1.ndigit,
"_neupd: Last row of the eigenvector matrix for T");
if (msglvl > 3) {
igraphdmout_(&debug_1.logfil, ncv, ncv, &workl[invsub], &ldq, &
debug_1.ndigit, "_neupd: The eigenvector matrix "
"for T");
}
}
/* %---------------------------------------% */
/* | Copy Ritz estimates into workl(ihbds) | */
/* %---------------------------------------% */
igraphdcopy_(&nconv, &workev[1], &c__1, &workl[ihbds], &c__1);
/* %---------------------------------------------------------% */
/* | Compute the QR factorization of the eigenvector matrix | */
/* | associated with leading portion of T in the first NCONV | */
/* | columns of workl(invsub,ldq). | */
/* %---------------------------------------------------------% */
igraphdgeqr2_(ncv, &nconv, &workl[invsub], &ldq, &workev[1], &workev[*
ncv + 1], &ierr);
/* %----------------------------------------------% */
/* | * Postmultiply Z by Q. | */
/* | * Postmultiply Z by R. | */
/* | The N by NCONV matrix Z is now contains the | */
/* | Ritz vectors associated with the Ritz values | */
/* | in workl(iheigr) and workl(iheigi). | */
/* %----------------------------------------------% */
igraphdorm2r_("Right", "Notranspose", n, ncv, &nconv, &workl[invsub], &
ldq, &workev[1], &z__[z_offset], ldz, &workd[*n + 1], &
ierr);
igraphdtrmm_("Right", "Upper", "No transpose", "Non-unit", n, &nconv, &
c_b38, &workl[invsub], &ldq, &z__[z_offset], ldz);
}
} else {
/* %------------------------------------------------------% */
/* | An approximate invariant subspace is not needed. | */
/* | Place the Ritz values computed DNAUPD into DR and DI | */
/* %------------------------------------------------------% */
igraphdcopy_(&nconv, &workl[ritzr], &c__1, &dr[1], &c__1);
igraphdcopy_(&nconv, &workl[ritzi], &c__1, &di[1], &c__1);
igraphdcopy_(&nconv, &workl[ritzr], &c__1, &workl[iheigr], &c__1);
igraphdcopy_(&nconv, &workl[ritzi], &c__1, &workl[iheigi], &c__1);
igraphdcopy_(&nconv, &workl[bounds], &c__1, &workl[ihbds], &c__1);
}
/* %------------------------------------------------% */
/* | Transform the Ritz values and possibly vectors | */
/* | and corresponding error bounds of OP to those | */
/* | of A*x = lambda*B*x. | */
/* %------------------------------------------------% */
if (igraphs_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) == 0) {
if (*rvec) {
igraphdscal_(ncv, &rnorm, &workl[ihbds], &c__1);
}
} else {
/* %---------------------------------------% */
/* | A spectral transformation was used. | */
/* | * Determine the Ritz estimates of the | */
/* | Ritz values in the original system. | */
/* %---------------------------------------% */
if (igraphs_cmp(type__, "SHIFTI", (ftnlen)6, (ftnlen)6) == 0) {
if (*rvec) {
igraphdscal_(ncv, &rnorm, &workl[ihbds], &c__1);
}
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
temp = igraphdlapy2_(&workl[iheigr + k - 1], &workl[iheigi + k - 1])
;
workl[ihbds + k - 1] = (d__1 = workl[ihbds + k - 1], abs(d__1)
) / temp / temp;
/* L50: */
}
} else if (igraphs_cmp(type__, "REALPT", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
/* L60: */
}
} else if (igraphs_cmp(type__, "IMAGPT", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
/* L70: */
}
}
/* %-----------------------------------------------------------% */
/* | * Transform the Ritz values back to the original system. | */
/* | For TYPE = 'SHIFTI' the transformation is | */
/* | lambda = 1/theta + sigma | */
/* | For TYPE = 'REALPT' or 'IMAGPT' the user must from | */
/* | Rayleigh quotients or a projection. See remark 3 above.| */
/* | NOTES: | */
/* | *The Ritz vectors are not affected by the transformation. | */
/* %-----------------------------------------------------------% */
if (igraphs_cmp(type__, "SHIFTI", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
temp = igraphdlapy2_(&workl[iheigr + k - 1], &workl[iheigi + k - 1])
;
workl[iheigr + k - 1] = workl[iheigr + k - 1] / temp / temp +
*sigmar;
workl[iheigi + k - 1] = -workl[iheigi + k - 1] / temp / temp
+ *sigmai;
/* L80: */
}
igraphdcopy_(&nconv, &workl[iheigr], &c__1, &dr[1], &c__1);
igraphdcopy_(&nconv, &workl[iheigi], &c__1, &di[1], &c__1);
} else if (igraphs_cmp(type__, "REALPT", (ftnlen)6, (ftnlen)6) == 0 ||
igraphs_cmp(type__, "IMAGPT", (ftnlen)6, (ftnlen)6) == 0) {
igraphdcopy_(&nconv, &workl[iheigr], &c__1, &dr[1], &c__1);
igraphdcopy_(&nconv, &workl[iheigi], &c__1, &di[1], &c__1);
}
}
if (igraphs_cmp(type__, "SHIFTI", (ftnlen)6, (ftnlen)6) == 0 && msglvl > 1) {
igraphdvout_(&debug_1.logfil, &nconv, &dr[1], &debug_1.ndigit, "_neupd: Un"
"transformed real part of the Ritz valuess.");
igraphdvout_(&debug_1.logfil, &nconv, &di[1], &debug_1.ndigit, "_neupd: Un"
"transformed imag part of the Ritz valuess.");
igraphdvout_(&debug_1.logfil, &nconv, &workl[ihbds], &debug_1.ndigit, "_ne"
"upd: Ritz estimates of untransformed Ritz values.");
} else if (igraphs_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) == 0 && msglvl >
1) {
igraphdvout_(&debug_1.logfil, &nconv, &dr[1], &debug_1.ndigit, "_neupd: Re"
"al parts of converged Ritz values.");
igraphdvout_(&debug_1.logfil, &nconv, &di[1], &debug_1.ndigit, "_neupd: Im"
"ag parts of converged Ritz values.");
igraphdvout_(&debug_1.logfil, &nconv, &workl[ihbds], &debug_1.ndigit, "_ne"
"upd: Associated Ritz estimates.");
}
/* %-------------------------------------------------% */
/* | Eigenvector Purification step. Formally perform | */
/* | one of inverse subspace iteration. Only used | */
/* | for MODE = 2. | */
/* %-------------------------------------------------% */
if (*rvec && *(unsigned char *)howmny == 'A' && igraphs_cmp(type__, "SHIFTI"
, (ftnlen)6, (ftnlen)6) == 0) {
/* %------------------------------------------------% */
/* | Purify the computed Ritz vectors by adding a | */
/* | little bit of the residual vector: | */
/* | T | */
/* | resid(:)*( e s ) / theta | */
/* | NCV | */
/* | where H s = s theta. Remember that when theta | */
/* | has nonzero imaginary part, the corresponding | */
/* | Ritz vector is stored across two columns of Z. | */
/* %------------------------------------------------% */
iconj = 0;
i__1 = nconv;
for (j = 1; j <= i__1; ++j) {
if (workl[iheigi + j - 1] == 0.) {
workev[j] = workl[invsub + (j - 1) * ldq + *ncv - 1] / workl[
iheigr + j - 1];
} else if (iconj == 0) {
temp = igraphdlapy2_(&workl[iheigr + j - 1], &workl[iheigi + j - 1])
;
workev[j] = (workl[invsub + (j - 1) * ldq + *ncv - 1] * workl[
iheigr + j - 1] + workl[invsub + j * ldq + *ncv - 1] *
workl[iheigi + j - 1]) / temp / temp;
workev[j + 1] = (workl[invsub + j * ldq + *ncv - 1] * workl[
iheigr + j - 1] - workl[invsub + (j - 1) * ldq + *ncv
- 1] * workl[iheigi + j - 1]) / temp / temp;
iconj = 1;
} else {
iconj = 0;
}
/* L110: */
}
/* %---------------------------------------% */
/* | Perform a rank one update to Z and | */
/* | purify all the Ritz vectors together. | */
/* %---------------------------------------% */
igraphdger_(n, &nconv, &c_b38, &resid[1], &c__1, &workev[1], &c__1, &z__[
z_offset], ldz);
}
L9000:
return 0;
/* %---------------% */
/* | End of DNEUPD | */
/* %---------------% */
} /* dneupd_ */
/* Subroutine */ int igraphdnaitr_(integer *ido, char *bmat, integer *n, integer *k,
integer *np, integer *nb, doublereal *resid, doublereal *rnorm,
doublereal *v, integer *ldv, doublereal *h__, integer *ldh, integer *
ipntr, doublereal *workd, integer *info)
{
/* Initialized data */
static logical first = TRUE_;
/* System generated locals */
integer h_dim1, h_offset, v_dim1, v_offset, i__1, i__2;
doublereal d__1, d__2;
/* Builtin functions */
double sqrt(doublereal);
/* Local variables */
static integer i__, j;
static real t0, t1, t2, t3, t4, t5;
static integer jj, ipj, irj, ivj;
static doublereal ulp, tst1;
extern doublereal igraphddot_(integer *, doublereal *, integer *, doublereal *,
integer *);
static integer ierr, iter;
static doublereal unfl, ovfl;
static integer itry;
extern doublereal igraphdnrm2_(integer *, doublereal *, integer *);
static doublereal temp1;
static logical orth1, orth2, step3, step4;
static doublereal betaj;
extern /* Subroutine */ int igraphdscal_(integer *, doublereal *, doublereal *,
integer *), igraphdgemv_(char *, integer *, integer *, doublereal *,
doublereal *, integer *, doublereal *, integer *, doublereal *,
doublereal *, integer *);
static integer infol;
extern /* Subroutine */ int igraphdcopy_(integer *, doublereal *, integer *,
doublereal *, integer *), igraphdaxpy_(integer *, doublereal *,
doublereal *, integer *, doublereal *, integer *), igraphdmout_(integer
*, integer *, integer *, doublereal *, integer *, integer *, char
*);
static doublereal xtemp[2];
extern /* Subroutine */ int igraphdvout_(integer *, integer *, doublereal *,
integer *, char *);
static doublereal wnorm;
extern /* Subroutine */ int igraphivout_(integer *, integer *, integer *,
integer *, char *), igraphdgetv0_(integer *, char *, integer *,
logical *, integer *, integer *, doublereal *, integer *,
doublereal *, doublereal *, integer *, doublereal *, integer *
), igraphdlabad_(doublereal *, doublereal *);
static doublereal rnorm1;
extern doublereal igraphdlamch_(char *);
extern /* Subroutine */ int igraphdlascl_(char *, integer *, integer *,
doublereal *, doublereal *, integer *, integer *, doublereal *,
integer *, integer *);
extern doublereal igraphdlanhs_(char *, integer *, doublereal *, integer *,
doublereal *);
extern /* Subroutine */ int igraphsecond_(real *);
static logical rstart;
static integer msglvl;
static doublereal smlnum;
/* %----------------------------------------------------% */
/* | Include files for debugging and timing information | */
/* %----------------------------------------------------% */
/* \SCCS Information: @(#) */
/* FILE: debug.h SID: 2.3 DATE OF SID: 11/16/95 RELEASE: 2 */
/* %---------------------------------% */
/* | See debug.doc for documentation | */
/* %---------------------------------% */
/* %------------------% */
/* | Scalar Arguments | */
/* %------------------% */
/* %--------------------------------% */
/* | See stat.doc for documentation | */
/* %--------------------------------% */
/* \SCCS Information: @(#) */
/* FILE: stat.h SID: 2.2 DATE OF SID: 11/16/95 RELEASE: 2 */
/* %-----------------% */
/* | Array Arguments | */
/* %-----------------% */
/* %------------% */
/* | Parameters | */
/* %------------% */
/* %---------------% */
/* | Local Scalars | */
/* %---------------% */
/* %-----------------------% */
/* | Local Array Arguments | */
/* %-----------------------% */
/* %----------------------% */
/* | External Subroutines | */
/* %----------------------% */
/* %--------------------% */
/* | External Functions | */
/* %--------------------% */
/* %---------------------% */
/* | Intrinsic Functions | */
/* %---------------------% */
/* %-----------------% */
/* | Data statements | */
/* %-----------------% */
/* Parameter adjustments */
--workd;
--resid;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
h_dim1 = *ldh;
h_offset = 1 + h_dim1;
h__ -= h_offset;
--ipntr;
/* Function Body */
/* %-----------------------% */
/* | Executable Statements | */
/* %-----------------------% */
if (first) {
/* %-----------------------------------------% */
/* | Set machine-dependent constants for the | */
/* | the splitting and deflation criterion. | */
/* | If norm(H) <= sqrt(OVFL), | */
/* | overflow should not occur. | */
/* | REFERENCE: LAPACK subroutine dlahqr | */
/* %-----------------------------------------% */
unfl = igraphdlamch_("safe minimum");
ovfl = 1. / unfl;
igraphdlabad_(&unfl, &ovfl);
ulp = igraphdlamch_("precision");
smlnum = unfl * (*n / ulp);
first = FALSE_;
}
if (*ido == 0) {
/* %-------------------------------% */
/* | Initialize timing statistics | */
/* | & message level for debugging | */
/* %-------------------------------% */
igraphsecond_(&t0);
msglvl = debug_1.mnaitr;
/* %------------------------------% */
/* | Initial call to this routine | */
/* %------------------------------% */
*info = 0;
step3 = FALSE_;
step4 = FALSE_;
rstart = FALSE_;
orth1 = FALSE_;
orth2 = FALSE_;
j = *k + 1;
ipj = 1;
irj = ipj + *n;
ivj = irj + *n;
}
/* %-------------------------------------------------% */
/* | When in reverse communication mode one of: | */
/* | STEP3, STEP4, ORTH1, ORTH2, RSTART | */
/* | will be .true. when .... | */
/* | STEP3: return from computing OP*v_{j}. | */
/* | STEP4: return from computing B-norm of OP*v_{j} | */
/* | ORTH1: return from computing B-norm of r_{j+1} | */
/* | ORTH2: return from computing B-norm of | */
/* | correction to the residual vector. | */
/* | RSTART: return from OP computations needed by | */
/* | dgetv0. | */
/* %-------------------------------------------------% */
if (step3) {
goto L50;
}
if (step4) {
goto L60;
}
if (orth1) {
goto L70;
}
if (orth2) {
goto L90;
}
if (rstart) {
goto L30;
}
/* %-----------------------------% */
/* | Else this is the first step | */
/* %-----------------------------% */
/* %--------------------------------------------------------------% */
/* | | */
/* | A R N O L D I I T E R A T I O N L O O P | */
/* | | */
/* | Note: B*r_{j-1} is already in WORKD(1:N)=WORKD(IPJ:IPJ+N-1) | */
/* %--------------------------------------------------------------% */
L1000:
if (msglvl > 1) {
igraphivout_(&debug_1.logfil, &c__1, &j, &debug_1.ndigit, "_naitr: generat"
"ing Arnoldi vector number");
igraphdvout_(&debug_1.logfil, &c__1, rnorm, &debug_1.ndigit, "_naitr: B-no"
"rm of the current residual is");
}
/* %---------------------------------------------------% */
/* | STEP 1: Check if the B norm of j-th residual | */
/* | vector is zero. Equivalent to determing whether | */
/* | an exact j-step Arnoldi factorization is present. | */
/* %---------------------------------------------------% */
betaj = *rnorm;
if (*rnorm > 0.) {
goto L40;
}
/* %---------------------------------------------------% */
/* | Invariant subspace found, generate a new starting | */
/* | vector which is orthogonal to the current Arnoldi | */
/* | basis and continue the iteration. | */
/* %---------------------------------------------------% */
if (msglvl > 0) {
igraphivout_(&debug_1.logfil, &c__1, &j, &debug_1.ndigit, "_naitr: ****** "
"RESTART AT STEP ******");
}
/* %---------------------------------------------% */
/* | ITRY is the loop variable that controls the | */
/* | maximum amount of times that a restart is | */
/* | attempted. NRSTRT is used by stat.h | */
/* %---------------------------------------------% */
betaj = 0.;
++timing_1.nrstrt;
itry = 1;
L20:
rstart = TRUE_;
*ido = 0;
L30:
/* %--------------------------------------% */
/* | If in reverse communication mode and | */
/* | RSTART = .true. flow returns here. | */
/* %--------------------------------------% */
igraphdgetv0_(ido, bmat, &itry, &c_false, n, &j, &v[v_offset], ldv, &resid[1],
rnorm, &ipntr[1], &workd[1], &ierr);
if (*ido != 99) {
goto L9000;
}
if (ierr < 0) {
++itry;
if (itry <= 3) {
goto L20;
}
/* %------------------------------------------------% */
/* | Give up after several restart attempts. | */
/* | Set INFO to the size of the invariant subspace | */
/* | which spans OP and exit. | */
/* %------------------------------------------------% */
*info = j - 1;
igraphsecond_(&t1);
timing_1.tnaitr += t1 - t0;
*ido = 99;
goto L9000;
}
L40:
/* %---------------------------------------------------------% */
/* | STEP 2: v_{j} = r_{j-1}/rnorm and p_{j} = p_{j}/rnorm | */
/* | Note that p_{j} = B*r_{j-1}. In order to avoid overflow | */
/* | when reciprocating a small RNORM, test against lower | */
/* | machine bound. | */
/* %---------------------------------------------------------% */
igraphdcopy_(n, &resid[1], &c__1, &v[j * v_dim1 + 1], &c__1);
if (*rnorm >= unfl) {
temp1 = 1. / *rnorm;
igraphdscal_(n, &temp1, &v[j * v_dim1 + 1], &c__1);
igraphdscal_(n, &temp1, &workd[ipj], &c__1);
} else {
/* %-----------------------------------------% */
/* | To scale both v_{j} and p_{j} carefully | */
/* | use LAPACK routine SLASCL | */
/* %-----------------------------------------% */
igraphdlascl_("General", &i__, &i__, rnorm, &c_b25, n, &c__1, &v[j * v_dim1
+ 1], n, &infol);
igraphdlascl_("General", &i__, &i__, rnorm, &c_b25, n, &c__1, &workd[ipj],
n, &infol);
}
/* %------------------------------------------------------% */
/* | STEP 3: r_{j} = OP*v_{j}; Note that p_{j} = B*v_{j} | */
/* | Note that this is not quite yet r_{j}. See STEP 4 | */
/* %------------------------------------------------------% */
step3 = TRUE_;
++timing_1.nopx;
igraphsecond_(&t2);
igraphdcopy_(n, &v[j * v_dim1 + 1], &c__1, &workd[ivj], &c__1);
ipntr[1] = ivj;
ipntr[2] = irj;
ipntr[3] = ipj;
*ido = 1;
/* %-----------------------------------% */
/* | Exit in order to compute OP*v_{j} | */
/* %-----------------------------------% */
goto L9000;
L50:
/* %----------------------------------% */
/* | Back from reverse communication; | */
/* | WORKD(IRJ:IRJ+N-1) := OP*v_{j} | */
/* | if step3 = .true. | */
/* %----------------------------------% */
igraphsecond_(&t3);
timing_1.tmvopx += t3 - t2;
step3 = FALSE_;
/* %------------------------------------------% */
/* | Put another copy of OP*v_{j} into RESID. | */
/* %------------------------------------------% */
igraphdcopy_(n, &workd[irj], &c__1, &resid[1], &c__1);
/* %---------------------------------------% */
/* | STEP 4: Finish extending the Arnoldi | */
/* | factorization to length j. | */
/* %---------------------------------------% */
igraphsecond_(&t2);
if (*(unsigned char *)bmat == 'G') {
++timing_1.nbx;
step4 = TRUE_;
ipntr[1] = irj;
ipntr[2] = ipj;
*ido = 2;
/* %-------------------------------------% */
/* | Exit in order to compute B*OP*v_{j} | */
/* %-------------------------------------% */
goto L9000;
} else if (*(unsigned char *)bmat == 'I') {
igraphdcopy_(n, &resid[1], &c__1, &workd[ipj], &c__1);
}
L60:
/* %----------------------------------% */
/* | Back from reverse communication; | */
/* | WORKD(IPJ:IPJ+N-1) := B*OP*v_{j} | */
/* | if step4 = .true. | */
/* %----------------------------------% */
if (*(unsigned char *)bmat == 'G') {
igraphsecond_(&t3);
timing_1.tmvbx += t3 - t2;
}
step4 = FALSE_;
/* %-------------------------------------% */
/* | The following is needed for STEP 5. | */
/* | Compute the B-norm of OP*v_{j}. | */
/* %-------------------------------------% */
if (*(unsigned char *)bmat == 'G') {
wnorm = igraphddot_(n, &resid[1], &c__1, &workd[ipj], &c__1);
wnorm = sqrt((abs(wnorm)));
} else if (*(unsigned char *)bmat == 'I') {
wnorm = igraphdnrm2_(n, &resid[1], &c__1);
}
/* %-----------------------------------------% */
/* | Compute the j-th residual corresponding | */
/* | to the j step factorization. | */
/* | Use Classical Gram Schmidt and compute: | */
/* | w_{j} <- V_{j}^T * B * OP * v_{j} | */
/* | r_{j} <- OP*v_{j} - V_{j} * w_{j} | */
/* %-----------------------------------------% */
/* %------------------------------------------% */
/* | Compute the j Fourier coefficients w_{j} | */
/* | WORKD(IPJ:IPJ+N-1) contains B*OP*v_{j}. | */
/* %------------------------------------------% */
igraphdgemv_("T", n, &j, &c_b25, &v[v_offset], ldv, &workd[ipj], &c__1, &c_b47,
&h__[j * h_dim1 + 1], &c__1);
/* %--------------------------------------% */
/* | Orthogonalize r_{j} against V_{j}. | */
/* | RESID contains OP*v_{j}. See STEP 3. | */
/* %--------------------------------------% */
igraphdgemv_("N", n, &j, &c_b50, &v[v_offset], ldv, &h__[j * h_dim1 + 1], &c__1,
&c_b25, &resid[1], &c__1);
if (j > 1) {
h__[j + (j - 1) * h_dim1] = betaj;
}
igraphsecond_(&t4);
orth1 = TRUE_;
igraphsecond_(&t2);
if (*(unsigned char *)bmat == 'G') {
++timing_1.nbx;
igraphdcopy_(n, &resid[1], &c__1, &workd[irj], &c__1);
ipntr[1] = irj;
ipntr[2] = ipj;
*ido = 2;
/* %----------------------------------% */
/* | Exit in order to compute B*r_{j} | */
/* %----------------------------------% */
goto L9000;
} else if (*(unsigned char *)bmat == 'I') {
igraphdcopy_(n, &resid[1], &c__1, &workd[ipj], &c__1);
}
L70:
/* %---------------------------------------------------% */
/* | Back from reverse communication if ORTH1 = .true. | */
/* | WORKD(IPJ:IPJ+N-1) := B*r_{j}. | */
/* %---------------------------------------------------% */
if (*(unsigned char *)bmat == 'G') {
igraphsecond_(&t3);
timing_1.tmvbx += t3 - t2;
}
orth1 = FALSE_;
/* %------------------------------% */
/* | Compute the B-norm of r_{j}. | */
/* %------------------------------% */
if (*(unsigned char *)bmat == 'G') {
*rnorm = igraphddot_(n, &resid[1], &c__1, &workd[ipj], &c__1);
*rnorm = sqrt((abs(*rnorm)));
} else if (*(unsigned char *)bmat == 'I') {
*rnorm = igraphdnrm2_(n, &resid[1], &c__1);
}
/* %-----------------------------------------------------------% */
/* | STEP 5: Re-orthogonalization / Iterative refinement phase | */
/* | Maximum NITER_ITREF tries. | */
/* | | */
/* | s = V_{j}^T * B * r_{j} | */
/* | r_{j} = r_{j} - V_{j}*s | */
/* | alphaj = alphaj + s_{j} | */
/* | | */
/* | The stopping criteria used for iterative refinement is | */
/* | discussed in Parlett's book SEP, page 107 and in Gragg & | */
/* | Reichel ACM TOMS paper; Algorithm 686, Dec. 1990. | */
/* | Determine if we need to correct the residual. The goal is | */
/* | to enforce ||v(:,1:j)^T * r_{j}|| .le. eps * || r_{j} || | */
/* | The following test determines whether the sine of the | */
/* | angle between OP*x and the computed residual is less | */
/* | than or equal to 0.717. | */
/* %-----------------------------------------------------------% */
if (*rnorm > wnorm * .717f) {
goto L100;
}
iter = 0;
++timing_1.nrorth;
/* %---------------------------------------------------% */
/* | Enter the Iterative refinement phase. If further | */
/* | refinement is necessary, loop back here. The loop | */
/* | variable is ITER. Perform a step of Classical | */
/* | Gram-Schmidt using all the Arnoldi vectors V_{j} | */
/* %---------------------------------------------------% */
L80:
if (msglvl > 2) {
xtemp[0] = wnorm;
xtemp[1] = *rnorm;
igraphdvout_(&debug_1.logfil, &c__2, xtemp, &debug_1.ndigit, "_naitr: re-o"
"rthonalization; wnorm and rnorm are");
igraphdvout_(&debug_1.logfil, &j, &h__[j * h_dim1 + 1], &debug_1.ndigit,
"_naitr: j-th column of H");
}
/* %----------------------------------------------------% */
/* | Compute V_{j}^T * B * r_{j}. | */
/* | WORKD(IRJ:IRJ+J-1) = v(:,1:J)'*WORKD(IPJ:IPJ+N-1). | */
/* %----------------------------------------------------% */
igraphdgemv_("T", n, &j, &c_b25, &v[v_offset], ldv, &workd[ipj], &c__1, &c_b47,
&workd[irj], &c__1);
/* %---------------------------------------------% */
/* | Compute the correction to the residual: | */
/* | r_{j} = r_{j} - V_{j} * WORKD(IRJ:IRJ+J-1). | */
/* | The correction to H is v(:,1:J)*H(1:J,1:J) | */
/* | + v(:,1:J)*WORKD(IRJ:IRJ+J-1)*e'_j. | */
/* %---------------------------------------------% */
igraphdgemv_("N", n, &j, &c_b50, &v[v_offset], ldv, &workd[irj], &c__1, &c_b25,
&resid[1], &c__1);
igraphdaxpy_(&j, &c_b25, &workd[irj], &c__1, &h__[j * h_dim1 + 1], &c__1);
orth2 = TRUE_;
igraphsecond_(&t2);
if (*(unsigned char *)bmat == 'G') {
++timing_1.nbx;
igraphdcopy_(n, &resid[1], &c__1, &workd[irj], &c__1);
ipntr[1] = irj;
ipntr[2] = ipj;
*ido = 2;
/* %-----------------------------------% */
/* | Exit in order to compute B*r_{j}. | */
/* | r_{j} is the corrected residual. | */
/* %-----------------------------------% */
goto L9000;
} else if (*(unsigned char *)bmat == 'I') {
igraphdcopy_(n, &resid[1], &c__1, &workd[ipj], &c__1);
}
L90:
/* %---------------------------------------------------% */
/* | Back from reverse communication if ORTH2 = .true. | */
/* %---------------------------------------------------% */
if (*(unsigned char *)bmat == 'G') {
igraphsecond_(&t3);
timing_1.tmvbx += t3 - t2;
}
/* %-----------------------------------------------------% */
/* | Compute the B-norm of the corrected residual r_{j}. | */
/* %-----------------------------------------------------% */
if (*(unsigned char *)bmat == 'G') {
rnorm1 = igraphddot_(n, &resid[1], &c__1, &workd[ipj], &c__1);
rnorm1 = sqrt((abs(rnorm1)));
} else if (*(unsigned char *)bmat == 'I') {
rnorm1 = igraphdnrm2_(n, &resid[1], &c__1);
}
if (msglvl > 0 && iter > 0) {
igraphivout_(&debug_1.logfil, &c__1, &j, &debug_1.ndigit, "_naitr: Iterati"
"ve refinement for Arnoldi residual");
if (msglvl > 2) {
xtemp[0] = *rnorm;
xtemp[1] = rnorm1;
igraphdvout_(&debug_1.logfil, &c__2, xtemp, &debug_1.ndigit, "_naitr: "
"iterative refinement ; rnorm and rnorm1 are");
}
}
/* %-----------------------------------------% */
/* | Determine if we need to perform another | */
/* | step of re-orthogonalization. | */
/* %-----------------------------------------% */
if (rnorm1 > *rnorm * .717f) {
/* %---------------------------------------% */
/* | No need for further refinement. | */
/* | The cosine of the angle between the | */
/* | corrected residual vector and the old | */
/* | residual vector is greater than 0.717 | */
/* | In other words the corrected residual | */
/* | and the old residual vector share an | */
/* | angle of less than arcCOS(0.717) | */
/* %---------------------------------------% */
*rnorm = rnorm1;
} else {
/* %-------------------------------------------% */
/* | Another step of iterative refinement step | */
/* | is required. NITREF is used by stat.h | */
/* %-------------------------------------------% */
++timing_1.nitref;
*rnorm = rnorm1;
++iter;
if (iter <= 1) {
goto L80;
}
/* %-------------------------------------------------% */
/* | Otherwise RESID is numerically in the span of V | */
/* %-------------------------------------------------% */
i__1 = *n;
for (jj = 1; jj <= i__1; ++jj) {
resid[jj] = 0.;
/* L95: */
}
*rnorm = 0.;
}
/* %----------------------------------------------% */
/* | Branch here directly if iterative refinement | */
/* | wasn't necessary or after at most NITER_REF | */
/* | steps of iterative refinement. | */
/* %----------------------------------------------% */
L100:
rstart = FALSE_;
orth2 = FALSE_;
igraphsecond_(&t5);
timing_1.titref += t5 - t4;
/* %------------------------------------% */
/* | STEP 6: Update j = j+1; Continue | */
/* %------------------------------------% */
++j;
if (j > *k + *np) {
igraphsecond_(&t1);
timing_1.tnaitr += t1 - t0;
*ido = 99;
i__1 = *k + *np - 1;
for (i__ = max(1,*k); i__ <= i__1; ++i__) {
/* %--------------------------------------------% */
/* | Check for splitting and deflation. | */
/* | Use a standard test as in the QR algorithm | */
/* | REFERENCE: LAPACK subroutine dlahqr | */
/* %--------------------------------------------% */
tst1 = (d__1 = h__[i__ + i__ * h_dim1], abs(d__1)) + (d__2 = h__[
i__ + 1 + (i__ + 1) * h_dim1], abs(d__2));
if (tst1 == 0.) {
i__2 = *k + *np;
tst1 = igraphdlanhs_("1", &i__2, &h__[h_offset], ldh, &workd[*n + 1]);
}
/* Computing MAX */
d__2 = ulp * tst1;
if ((d__1 = h__[i__ + 1 + i__ * h_dim1], abs(d__1)) <= max(d__2,
smlnum)) {
h__[i__ + 1 + i__ * h_dim1] = 0.;
}
/* L110: */
}
if (msglvl > 2) {
i__1 = *k + *np;
i__2 = *k + *np;
igraphdmout_(&debug_1.logfil, &i__1, &i__2, &h__[h_offset], ldh, &
debug_1.ndigit, "_naitr: Final upper Hessenberg matrix H"
" of order K+NP");
}
goto L9000;
}
/* %--------------------------------------------------------% */
/* | Loop back to extend the factorization by another step. | */
/* %--------------------------------------------------------% */
goto L1000;
/* %---------------------------------------------------------------% */
/* | | */
/* | E N D O F M A I N I T E R A T I O N L O O P | */
/* | | */
/* %---------------------------------------------------------------% */
L9000:
return 0;
/* %---------------% */
/* | End of igraphdnaitr | */
/* %---------------% */
} /* igraphdnaitr_ */
Subroutine */ int igraphdsaup2_(integer *ido, char *bmat, integer *n, char *
which, integer *nev, integer *np, doublereal *tol, doublereal *resid,
integer *mode, integer *iupd, integer *ishift, integer *mxiter,
doublereal *v, integer *ldv, doublereal *h__, integer *ldh,
doublereal *ritz, doublereal *bounds, doublereal *q, integer *ldq,
doublereal *workl, integer *ipntr, doublereal *workd, integer *info)
{
/* System generated locals */
integer h_dim1, h_offset, q_dim1, q_offset, v_dim1, v_offset, i__1, i__2,
i__3;
doublereal d__1, d__2, d__3;
/* Builtin functions */
double pow_dd(doublereal *, doublereal *);
integer s_cmp(char *, char *, ftnlen, ftnlen);
/* Subroutine */ int s_copy(char *, char *, ftnlen, ftnlen);
double sqrt(doublereal);
/* Local variables */
integer j;
real t0, t1, t2, t3;
integer kp[3];
IGRAPH_F77_SAVE integer np0;
integer nbx = 0;
IGRAPH_F77_SAVE integer nev0;
extern doublereal igraphddot_(integer *, doublereal *, integer *, doublereal *,
integer *);
IGRAPH_F77_SAVE doublereal eps23;
integer ierr;
IGRAPH_F77_SAVE integer iter;
doublereal temp;
integer nevd2;
extern doublereal igraphdnrm2_(integer *, doublereal *, integer *);
IGRAPH_F77_SAVE logical getv0;
integer nevm2;
IGRAPH_F77_SAVE logical cnorm;
extern /* Subroutine */ int igraphdcopy_(integer *, doublereal *, integer *,
doublereal *, integer *), igraphdswap_(integer *, doublereal *, integer
*, doublereal *, integer *);
IGRAPH_F77_SAVE integer nconv;
IGRAPH_F77_SAVE logical initv;
IGRAPH_F77_SAVE doublereal rnorm;
real tmvbx = 0.0;
extern /* Subroutine */ int igraphdvout_(integer *, integer *, doublereal *,
integer *, char *, ftnlen), igraphivout_(integer *, integer *, integer *
, integer *, char *, ftnlen), igraphdgetv0_(integer *, char *, integer *
, logical *, integer *, integer *, doublereal *, integer *,
doublereal *, doublereal *, integer *, doublereal *, integer *);
integer msaup2 = 0;
real tsaup2;
extern doublereal igraphdlamch_(char *);
integer nevbef;
extern /* Subroutine */ int igraphsecond_(real *);
integer logfil, ndigit;
extern /* Subroutine */ int igraphdseigt_(doublereal *, integer *, doublereal *,
integer *, doublereal *, doublereal *, doublereal *, integer *);
IGRAPH_F77_SAVE logical update;
extern /* Subroutine */ int igraphdsaitr_(integer *, char *, integer *, integer
*, integer *, integer *, doublereal *, doublereal *, doublereal *,
integer *, doublereal *, integer *, integer *, doublereal *,
integer *), igraphdsgets_(integer *, char *, integer *, integer
*, doublereal *, doublereal *, doublereal *), igraphdsapps_(
integer *, integer *, integer *, doublereal *, doublereal *,
integer *, doublereal *, integer *, doublereal *, doublereal *,
integer *, doublereal *), igraphdsconv_(integer *, doublereal *,
doublereal *, doublereal *, integer *);
IGRAPH_F77_SAVE logical ushift;
char wprime[2];
IGRAPH_F77_SAVE integer msglvl;
integer nptemp;
extern /* Subroutine */ int igraphdsortr_(char *, logical *, integer *,
doublereal *, doublereal *);
IGRAPH_F77_SAVE integer kplusp;
/* %----------------------------------------------------%
| Include files for debugging and timing information |
%----------------------------------------------------%
%------------------%
| Scalar Arguments |
%------------------%
%-----------------%
| Array Arguments |
%-----------------%
%------------%
| Parameters |
%------------%
%---------------%
| Local Scalars |
%---------------%
%----------------------%
| External Subroutines |
%----------------------%
%--------------------%
| External Functions |
%--------------------%
%---------------------%
| Intrinsic Functions |
%---------------------%
%-----------------------%
| Executable Statements |
%-----------------------%
Parameter adjustments */
--workd;
--resid;
--workl;
--bounds;
--ritz;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
h_dim1 = *ldh;
h_offset = 1 + h_dim1;
h__ -= h_offset;
q_dim1 = *ldq;
q_offset = 1 + q_dim1;
q -= q_offset;
--ipntr;
/* Function Body */
if (*ido == 0) {
/* %-------------------------------%
| Initialize timing statistics |
| & message level for debugging |
%-------------------------------% */
igraphsecond_(&t0);
msglvl = msaup2;
/* %---------------------------------%
| Set machine dependent constant. |
%---------------------------------% */
eps23 = igraphdlamch_("Epsilon-Machine");
eps23 = pow_dd(&eps23, &c_b3);
/* %-------------------------------------%
| nev0 and np0 are integer variables |
| hold the initial values of NEV & NP |
%-------------------------------------% */
nev0 = *nev;
np0 = *np;
/* %-------------------------------------%
| kplusp is the bound on the largest |
| Lanczos factorization built. |
| nconv is the current number of |
| "converged" eigenvlues. |
| iter is the counter on the current |
| iteration step. |
%-------------------------------------% */
kplusp = nev0 + np0;
nconv = 0;
iter = 0;
/* %--------------------------------------------%
| Set flags for computing the first NEV steps |
| of the Lanczos factorization. |
%--------------------------------------------% */
getv0 = TRUE_;
update = FALSE_;
ushift = FALSE_;
cnorm = FALSE_;
if (*info != 0) {
/* %--------------------------------------------%
| User provides the initial residual vector. |
%--------------------------------------------% */
initv = TRUE_;
*info = 0;
} else {
initv = FALSE_;
}
}
/* %---------------------------------------------%
| Get a possibly random starting vector and |
| force it into the range of the operator OP. |
%---------------------------------------------%
L10: */
if (getv0) {
igraphdgetv0_(ido, bmat, &c__1, &initv, n, &c__1, &v[v_offset], ldv, &resid[
1], &rnorm, &ipntr[1], &workd[1], info);
if (*ido != 99) {
goto L9000;
}
if (rnorm == 0.) {
/* %-----------------------------------------%
| The initial vector is zero. Error exit. |
%-----------------------------------------% */
*info = -9;
goto L1200;
}
getv0 = FALSE_;
*ido = 0;
}
/* %------------------------------------------------------------%
| Back from reverse communication: continue with update step |
%------------------------------------------------------------% */
if (update) {
goto L20;
}
/* %-------------------------------------------%
| Back from computing user specified shifts |
%-------------------------------------------% */
if (ushift) {
goto L50;
}
/* %-------------------------------------%
| Back from computing residual norm |
| at the end of the current iteration |
%-------------------------------------% */
if (cnorm) {
goto L100;
}
/* %----------------------------------------------------------%
| Compute the first NEV steps of the Lanczos factorization |
%----------------------------------------------------------% */
igraphdsaitr_(ido, bmat, n, &c__0, &nev0, mode, &resid[1], &rnorm, &v[v_offset],
ldv, &h__[h_offset], ldh, &ipntr[1], &workd[1], info);
/* %---------------------------------------------------%
| ido .ne. 99 implies use of reverse communication |
| to compute operations involving OP and possibly B |
%---------------------------------------------------% */
if (*ido != 99) {
goto L9000;
}
if (*info > 0) {
/* %-----------------------------------------------------%
| dsaitr was unable to build an Lanczos factorization |
| of length NEV0. INFO is returned with the size of |
| the factorization built. Exit main loop. |
%-----------------------------------------------------% */
*np = *info;
*mxiter = iter;
*info = -9999;
goto L1200;
}
/* %--------------------------------------------------------------%
| |
| M A I N LANCZOS I T E R A T I O N L O O P |
| Each iteration implicitly restarts the Lanczos |
| factorization in place. |
| |
%--------------------------------------------------------------% */
L1000:
++iter;
if (msglvl > 0) {
igraphivout_(&logfil, &c__1, &iter, &ndigit, "_saup2: **** Start of major "
"iteration number ****", (ftnlen)49);
}
if (msglvl > 1) {
igraphivout_(&logfil, &c__1, nev, &ndigit, "_saup2: The length of the curr"
"ent Lanczos factorization", (ftnlen)55);
igraphivout_(&logfil, &c__1, np, &ndigit, "_saup2: Extend the Lanczos fact"
"orization by", (ftnlen)43);
}
/* %------------------------------------------------------------%
| Compute NP additional steps of the Lanczos factorization. |
%------------------------------------------------------------% */
*ido = 0;
L20:
update = TRUE_;
igraphdsaitr_(ido, bmat, n, nev, np, mode, &resid[1], &rnorm, &v[v_offset], ldv,
&h__[h_offset], ldh, &ipntr[1], &workd[1], info);
/* %---------------------------------------------------%
| ido .ne. 99 implies use of reverse communication |
| to compute operations involving OP and possibly B |
%---------------------------------------------------% */
if (*ido != 99) {
goto L9000;
}
if (*info > 0) {
/* %-----------------------------------------------------%
| dsaitr was unable to build an Lanczos factorization |
| of length NEV0+NP0. INFO is returned with the size |
| of the factorization built. Exit main loop. |
%-----------------------------------------------------% */
*np = *info;
*mxiter = iter;
*info = -9999;
goto L1200;
}
update = FALSE_;
if (msglvl > 1) {
igraphdvout_(&logfil, &c__1, &rnorm, &ndigit, "_saup2: Current B-norm of r"
"esidual for factorization", (ftnlen)52);
}
/* %--------------------------------------------------------%
| Compute the eigenvalues and corresponding error bounds |
| of the current symmetric tridiagonal matrix. |
%--------------------------------------------------------% */
igraphdseigt_(&rnorm, &kplusp, &h__[h_offset], ldh, &ritz[1], &bounds[1], &
workl[1], &ierr);
if (ierr != 0) {
*info = -8;
goto L1200;
}
/* %----------------------------------------------------%
| Make a copy of eigenvalues and corresponding error |
| bounds obtained from _seigt. |
%----------------------------------------------------% */
igraphdcopy_(&kplusp, &ritz[1], &c__1, &workl[kplusp + 1], &c__1);
igraphdcopy_(&kplusp, &bounds[1], &c__1, &workl[(kplusp << 1) + 1], &c__1);
/* %---------------------------------------------------%
| Select the wanted Ritz values and their bounds |
| to be used in the convergence test. |
| The selection is based on the requested number of |
| eigenvalues instead of the current NEV and NP to |
| prevent possible misconvergence. |
| * Wanted Ritz values := RITZ(NP+1:NEV+NP) |
| * Shifts := RITZ(1:NP) := WORKL(1:NP) |
%---------------------------------------------------% */
*nev = nev0;
*np = np0;
igraphdsgets_(ishift, which, nev, np, &ritz[1], &bounds[1], &workl[1]);
/* %-------------------%
| Convergence test. |
%-------------------% */
igraphdcopy_(nev, &bounds[*np + 1], &c__1, &workl[*np + 1], &c__1);
igraphdsconv_(nev, &ritz[*np + 1], &workl[*np + 1], tol, &nconv);
if (msglvl > 2) {
kp[0] = *nev;
kp[1] = *np;
kp[2] = nconv;
igraphivout_(&logfil, &c__3, kp, &ndigit, "_saup2: NEV, NP, NCONV are", (
ftnlen)26);
igraphdvout_(&logfil, &kplusp, &ritz[1], &ndigit, "_saup2: The eigenvalues"
" of H", (ftnlen)28);
igraphdvout_(&logfil, &kplusp, &bounds[1], &ndigit, "_saup2: Ritz estimate"
"s of the current NCV Ritz values", (ftnlen)53);
}
/* %---------------------------------------------------------%
| Count the number of unwanted Ritz values that have zero |
| Ritz estimates. If any Ritz estimates are equal to zero |
| then a leading block of H of order equal to at least |
| the number of Ritz values with zero Ritz estimates has |
| split off. None of these Ritz values may be removed by |
| shifting. Decrease NP the number of shifts to apply. If |
| no shifts may be applied, then prepare to exit |
%---------------------------------------------------------% */
nptemp = *np;
i__1 = nptemp;
for (j = 1; j <= i__1; ++j) {
if (bounds[j] == 0.) {
--(*np);
++(*nev);
}
/* L30: */
}
if (nconv >= nev0 || iter > *mxiter || *np == 0) {
/* %------------------------------------------------%
| Prepare to exit. Put the converged Ritz values |
| and corresponding bounds in RITZ(1:NCONV) and |
| BOUNDS(1:NCONV) respectively. Then sort. Be |
| careful when NCONV > NP since we don't want to |
| swap overlapping locations. |
%------------------------------------------------% */
if (s_cmp(which, "BE", (ftnlen)2, (ftnlen)2) == 0) {
/* %-----------------------------------------------------%
| Both ends of the spectrum are requested. |
| Sort the eigenvalues into algebraically decreasing |
| order first then swap low end of the spectrum next |
| to high end in appropriate locations. |
| NOTE: when np < floor(nev/2) be careful not to swap |
| overlapping locations. |
%-----------------------------------------------------% */
s_copy(wprime, "SA", (ftnlen)2, (ftnlen)2);
igraphdsortr_(wprime, &c_true, &kplusp, &ritz[1], &bounds[1])
;
nevd2 = *nev / 2;
nevm2 = *nev - nevd2;
if (*nev > 1) {
i__1 = min(nevd2,*np);
/* Computing MAX */
i__2 = kplusp - nevd2 + 1, i__3 = kplusp - *np + 1;
igraphdswap_(&i__1, &ritz[nevm2 + 1], &c__1, &ritz[max(i__2,i__3)],
&c__1);
i__1 = min(nevd2,*np);
/* Computing MAX */
i__2 = kplusp - nevd2 + 1, i__3 = kplusp - *np;
igraphdswap_(&i__1, &bounds[nevm2 + 1], &c__1, &bounds[max(i__2,
i__3) + 1], &c__1);
}
} else {
/* %--------------------------------------------------%
| LM, SM, LA, SA case. |
| Sort the eigenvalues of H into the an order that |
| is opposite to WHICH, and apply the resulting |
| order to BOUNDS. The eigenvalues are sorted so |
| that the wanted part are always within the first |
| NEV locations. |
%--------------------------------------------------% */
if (s_cmp(which, "LM", (ftnlen)2, (ftnlen)2) == 0) {
s_copy(wprime, "SM", (ftnlen)2, (ftnlen)2);
}
if (s_cmp(which, "SM", (ftnlen)2, (ftnlen)2) == 0) {
s_copy(wprime, "LM", (ftnlen)2, (ftnlen)2);
}
if (s_cmp(which, "LA", (ftnlen)2, (ftnlen)2) == 0) {
s_copy(wprime, "SA", (ftnlen)2, (ftnlen)2);
}
if (s_cmp(which, "SA", (ftnlen)2, (ftnlen)2) == 0) {
s_copy(wprime, "LA", (ftnlen)2, (ftnlen)2);
}
igraphdsortr_(wprime, &c_true, &kplusp, &ritz[1], &bounds[1])
;
}
/* %--------------------------------------------------%
| Scale the Ritz estimate of each Ritz value |
| by 1 / max(eps23,magnitude of the Ritz value). |
%--------------------------------------------------% */
i__1 = nev0;
for (j = 1; j <= i__1; ++j) {
/* Computing MAX */
d__2 = eps23, d__3 = (d__1 = ritz[j], abs(d__1));
temp = max(d__2,d__3);
bounds[j] /= temp;
/* L35: */
}
/* %----------------------------------------------------%
| Sort the Ritz values according to the scaled Ritz |
| esitmates. This will push all the converged ones |
| towards the front of ritzr, ritzi, bounds |
| (in the case when NCONV < NEV.) |
%----------------------------------------------------% */
s_copy(wprime, "LA", (ftnlen)2, (ftnlen)2);
igraphdsortr_(wprime, &c_true, &nev0, &bounds[1], &ritz[1]);
/* %----------------------------------------------%
| Scale the Ritz estimate back to its original |
| value. |
%----------------------------------------------% */
i__1 = nev0;
for (j = 1; j <= i__1; ++j) {
/* Computing MAX */
d__2 = eps23, d__3 = (d__1 = ritz[j], abs(d__1));
temp = max(d__2,d__3);
bounds[j] *= temp;
/* L40: */
}
/* %--------------------------------------------------%
| Sort the "converged" Ritz values again so that |
| the "threshold" values and their associated Ritz |
| estimates appear at the appropriate position in |
| ritz and bound. |
%--------------------------------------------------% */
if (s_cmp(which, "BE", (ftnlen)2, (ftnlen)2) == 0) {
/* %------------------------------------------------%
| Sort the "converged" Ritz values in increasing |
| order. The "threshold" values are in the |
| middle. |
%------------------------------------------------% */
s_copy(wprime, "LA", (ftnlen)2, (ftnlen)2);
igraphdsortr_(wprime, &c_true, &nconv, &ritz[1], &bounds[1]);
} else {
/* %----------------------------------------------%
| In LM, SM, LA, SA case, sort the "converged" |
| Ritz values according to WHICH so that the |
| "threshold" value appears at the front of |
| ritz. |
%----------------------------------------------% */
igraphdsortr_(which, &c_true, &nconv, &ritz[1], &bounds[1]);
}
/* %------------------------------------------%
| Use h( 1,1 ) as storage to communicate |
| rnorm to _seupd if needed |
%------------------------------------------% */
h__[h_dim1 + 1] = rnorm;
if (msglvl > 1) {
igraphdvout_(&logfil, &kplusp, &ritz[1], &ndigit, "_saup2: Sorted Ritz"
" values.", (ftnlen)27);
igraphdvout_(&logfil, &kplusp, &bounds[1], &ndigit, "_saup2: Sorted ri"
"tz estimates.", (ftnlen)30);
}
/* %------------------------------------%
| Max iterations have been exceeded. |
%------------------------------------% */
if (iter > *mxiter && nconv < *nev) {
*info = 1;
}
/* %---------------------%
| No shifts to apply. |
%---------------------% */
if (*np == 0 && nconv < nev0) {
*info = 2;
}
*np = nconv;
goto L1100;
} else if (nconv < *nev && *ishift == 1) {
/* %---------------------------------------------------%
| Do not have all the requested eigenvalues yet. |
| To prevent possible stagnation, adjust the number |
| of Ritz values and the shifts. |
%---------------------------------------------------% */
nevbef = *nev;
/* Computing MIN */
i__1 = nconv, i__2 = *np / 2;
*nev += min(i__1,i__2);
if (*nev == 1 && kplusp >= 6) {
*nev = kplusp / 2;
} else if (*nev == 1 && kplusp > 2) {
*nev = 2;
}
*np = kplusp - *nev;
/* %---------------------------------------%
| If the size of NEV was just increased |
| resort the eigenvalues. |
%---------------------------------------% */
if (nevbef < *nev) {
igraphdsgets_(ishift, which, nev, np, &ritz[1], &bounds[1], &workl[1]);
}
}
if (msglvl > 0) {
igraphivout_(&logfil, &c__1, &nconv, &ndigit, "_saup2: no. of \"converge"
"d\" Ritz values at this iter.", (ftnlen)52);
if (msglvl > 1) {
kp[0] = *nev;
kp[1] = *np;
igraphivout_(&logfil, &c__2, kp, &ndigit, "_saup2: NEV and NP are", (
ftnlen)22);
igraphdvout_(&logfil, nev, &ritz[*np + 1], &ndigit, "_saup2: \"wante"
"d\" Ritz values.", (ftnlen)29);
igraphdvout_(&logfil, nev, &bounds[*np + 1], &ndigit, "_saup2: Ritz es"
"timates of the \"wanted\" values ", (ftnlen)46);
}
}
if (*ishift == 0) {
/* %-----------------------------------------------------%
| User specified shifts: reverse communication to |
| compute the shifts. They are returned in the first |
| NP locations of WORKL. |
%-----------------------------------------------------% */
ushift = TRUE_;
*ido = 3;
goto L9000;
}
L50:
/* %------------------------------------%
| Back from reverse communication; |
| User specified shifts are returned |
| in WORKL(1:*NP) |
%------------------------------------% */
ushift = FALSE_;
/* %---------------------------------------------------------%
| Move the NP shifts to the first NP locations of RITZ to |
| free up WORKL. This is for the non-exact shift case; |
| in the exact shift case, dsgets already handles this. |
%---------------------------------------------------------% */
if (*ishift == 0) {
igraphdcopy_(np, &workl[1], &c__1, &ritz[1], &c__1);
}
if (msglvl > 2) {
igraphivout_(&logfil, &c__1, np, &ndigit, "_saup2: The number of shifts to"
" apply ", (ftnlen)38);
igraphdvout_(&logfil, np, &workl[1], &ndigit, "_saup2: shifts selected", (
ftnlen)23);
if (*ishift == 1) {
igraphdvout_(&logfil, np, &bounds[1], &ndigit, "_saup2: corresponding "
"Ritz estimates", (ftnlen)36);
}
}
/* %---------------------------------------------------------%
| Apply the NP0 implicit shifts by QR bulge chasing. |
| Each shift is applied to the entire tridiagonal matrix. |
| The first 2*N locations of WORKD are used as workspace. |
| After dsapps is done, we have a Lanczos |
| factorization of length NEV. |
%---------------------------------------------------------% */
igraphdsapps_(n, nev, np, &ritz[1], &v[v_offset], ldv, &h__[h_offset], ldh, &
resid[1], &q[q_offset], ldq, &workd[1]);
/* %---------------------------------------------%
| Compute the B-norm of the updated residual. |
| Keep B*RESID in WORKD(1:N) to be used in |
| the first step of the next call to dsaitr. |
%---------------------------------------------% */
cnorm = TRUE_;
igraphsecond_(&t2);
if (*(unsigned char *)bmat == 'G') {
++nbx;
igraphdcopy_(n, &resid[1], &c__1, &workd[*n + 1], &c__1);
ipntr[1] = *n + 1;
ipntr[2] = 1;
*ido = 2;
/* %----------------------------------%
| Exit in order to compute B*RESID |
%----------------------------------% */
goto L9000;
} else if (*(unsigned char *)bmat == 'I') {
igraphdcopy_(n, &resid[1], &c__1, &workd[1], &c__1);
}
L100:
/* %----------------------------------%
| Back from reverse communication; |
| WORKD(1:N) := B*RESID |
%----------------------------------% */
if (*(unsigned char *)bmat == 'G') {
igraphsecond_(&t3);
tmvbx += t3 - t2;
}
if (*(unsigned char *)bmat == 'G') {
rnorm = igraphddot_(n, &resid[1], &c__1, &workd[1], &c__1);
rnorm = sqrt((abs(rnorm)));
} else if (*(unsigned char *)bmat == 'I') {
rnorm = igraphdnrm2_(n, &resid[1], &c__1);
}
cnorm = FALSE_;
/* L130: */
if (msglvl > 2) {
igraphdvout_(&logfil, &c__1, &rnorm, &ndigit, "_saup2: B-norm of residual "
"for NEV factorization", (ftnlen)48);
igraphdvout_(&logfil, nev, &h__[(h_dim1 << 1) + 1], &ndigit, "_saup2: main"
" diagonal of compressed H matrix", (ftnlen)44);
i__1 = *nev - 1;
igraphdvout_(&logfil, &i__1, &h__[h_dim1 + 2], &ndigit, "_saup2: subdiagon"
"al of compressed H matrix", (ftnlen)42);
}
goto L1000;
/* %---------------------------------------------------------------%
| |
| E N D O F M A I N I T E R A T I O N L O O P |
| |
%---------------------------------------------------------------% */
L1100:
*mxiter = iter;
*nev = nconv;
L1200:
*ido = 99;
/* %------------%
| Error exit |
%------------% */
igraphsecond_(&t1);
tsaup2 = t1 - t0;
L9000:
return 0;
/* %---------------%
| End of dsaup2 |
%---------------% */
} /* igraphdsaup2_ */
Subroutine */ int igraphdsaupd_(integer *ido, char *bmat, integer *n, char *
which, integer *nev, doublereal *tol, doublereal *resid, integer *ncv,
doublereal *v, integer *ldv, integer *iparam, integer *ipntr,
doublereal *workd, doublereal *workl, integer *lworkl, integer *info)
{
/* Format strings */
static char fmt_1000[] = "(//,5x,\002==================================="
"=======\002,/5x,\002= Symmetric implicit Arnoldi update code "
"=\002,/5x,\002= Version Number:\002,\002 2.4\002,19x,\002 =\002,"
"/5x,\002= Version Date: \002,\002 07/31/96\002,14x,\002 =\002,/"
"5x,\002==========================================\002,/5x,\002= "
"Summary of timing statistics =\002,/5x,\002==========="
"===============================\002,//)";
static char fmt_1100[] = "(5x,\002Total number update iterations "
" = \002,i5,/5x,\002Total number of OP*x operations "
" = \002,i5,/5x,\002Total number of B*x operations = "
"\002,i5,/5x,\002Total number of reorthogonalization steps = "
"\002,i5,/5x,\002Total number of iterative refinement steps = "
"\002,i5,/5x,\002Total number of restart steps = "
"\002,i5,/5x,\002Total time in user OP*x operation = "
"\002,f12.6,/5x,\002Total time in user B*x operation ="
" \002,f12.6,/5x,\002Total time in Arnoldi update routine = "
"\002,f12.6,/5x,\002Total time in saup2 routine ="
" \002,f12.6,/5x,\002Total time in basic Arnoldi iteration loop = "
"\002,f12.6,/5x,\002Total time in reorthogonalization phase ="
" \002,f12.6,/5x,\002Total time in (re)start vector generation = "
"\002,f12.6,/5x,\002Total time in trid eigenvalue subproblem ="
" \002,f12.6,/5x,\002Total time in getting the shifts = "
"\002,f12.6,/5x,\002Total time in applying the shifts ="
" \002,f12.6,/5x,\002Total time in convergence testing = "
"\002,f12.6)";
/* System generated locals */
integer v_dim1, v_offset, i__1, i__2;
/* Builtin functions */
integer s_cmp(char *, char *, ftnlen, ftnlen), s_wsfe(cilist *), e_wsfe(
void), do_fio(integer *, char *, ftnlen);
/* Local variables */
integer j;
real t0, t1;
IGRAPH_F77_SAVE integer nb, ih, iq, np, iw, ldh, ldq;
integer nbx;
IGRAPH_F77_SAVE integer nev0, mode, ierr, iupd, next;
integer nopx;
IGRAPH_F77_SAVE integer ritz;
real tmvbx;
extern /* Subroutine */ int igraphdvout_(integer *, integer *, doublereal *,
integer *, char *, ftnlen), igraphivout_(integer *, integer *, integer *
, integer *, char *, ftnlen), igraphdsaup2_(integer *, char *, integer *
, char *, integer *, integer *, doublereal *, doublereal *,
integer *, integer *, integer *, integer *, doublereal *, integer
*, doublereal *, integer *, doublereal *, doublereal *,
doublereal *, integer *, doublereal *, integer *, doublereal *,
integer *);
real tgetv0, tsaup2;
extern doublereal igraphdlamch_(char *);
extern /* Subroutine */ int igraphsecond_(real *);
integer logfil=0, ndigit;
IGRAPH_F77_SAVE integer ishift;
integer nitref, msaupd=0;
IGRAPH_F77_SAVE integer bounds;
real titref, tseigt, tsaupd;
extern /* Subroutine */ int igraphdstats_(void);
IGRAPH_F77_SAVE integer msglvl;
real tsaitr;
IGRAPH_F77_SAVE integer mxiter;
real tsgets, tsapps;
integer nrorth;
real tsconv;
integer nrstrt;
real tmvopx;
/* Fortran I/O blocks */
static cilist io___28 = { 0, 6, 0, fmt_1000, 0 };
static cilist io___29 = { 0, 6, 0, fmt_1100, 0 };
/* %----------------------------------------------------%
| Include files for debugging and timing information |
%----------------------------------------------------%
%------------------%
| Scalar Arguments |
%------------------%
%-----------------%
| Array Arguments |
%-----------------%
%------------%
| Parameters |
%------------%
%---------------%
| Local Scalars |
%---------------%
%----------------------%
| External Subroutines |
%----------------------%
%--------------------%
| External Functions |
%--------------------%
%-----------------------%
| Executable Statements |
%-----------------------%
Parameter adjustments */
--workd;
--resid;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
--iparam;
--ipntr;
--workl;
/* Function Body */
if (*ido == 0) {
/* %-------------------------------%
| Initialize timing statistics |
| & message level for debugging |
%-------------------------------% */
igraphdstats_();
igraphsecond_(&t0);
msglvl = msaupd;
ierr = 0;
ishift = iparam[1];
mxiter = iparam[3];
nb = iparam[4];
/* %--------------------------------------------%
| Revision 2 performs only implicit restart. |
%--------------------------------------------% */
iupd = 1;
mode = iparam[7];
/* %----------------%
| Error checking |
%----------------% */
if (*n <= 0) {
ierr = -1;
} else if (*nev <= 0) {
ierr = -2;
} else if (*ncv <= *nev || *ncv > *n) {
ierr = -3;
}
/* %----------------------------------------------%
| NP is the number of additional steps to |
| extend the length NEV Lanczos factorization. |
%----------------------------------------------% */
np = *ncv - *nev;
if (mxiter <= 0) {
ierr = -4;
}
if (s_cmp(which, "LM", (ftnlen)2, (ftnlen)2) != 0 && s_cmp(which,
"SM", (ftnlen)2, (ftnlen)2) != 0 && s_cmp(which, "LA", (
ftnlen)2, (ftnlen)2) != 0 && s_cmp(which, "SA", (ftnlen)2, (
ftnlen)2) != 0 && s_cmp(which, "BE", (ftnlen)2, (ftnlen)2) !=
0) {
ierr = -5;
}
if (*(unsigned char *)bmat != 'I' && *(unsigned char *)bmat != 'G') {
ierr = -6;
}
/* Computing 2nd power */
i__1 = *ncv;
if (*lworkl < i__1 * i__1 + (*ncv << 3)) {
ierr = -7;
}
if (mode < 1 || mode > 5) {
ierr = -10;
} else if (mode == 1 && *(unsigned char *)bmat == 'G') {
ierr = -11;
} else if (ishift < 0 || ishift > 1) {
ierr = -12;
} else if (*nev == 1 && s_cmp(which, "BE", (ftnlen)2, (ftnlen)2) == 0)
{
ierr = -13;
}
/* %------------%
| Error Exit |
%------------% */
if (ierr != 0) {
*info = ierr;
*ido = 99;
goto L9000;
}
/* %------------------------%
| Set default parameters |
%------------------------% */
if (nb <= 0) {
nb = 1;
}
if (*tol <= 0.) {
*tol = igraphdlamch_("EpsMach");
}
/* %----------------------------------------------%
| NP is the number of additional steps to |
| extend the length NEV Lanczos factorization. |
| NEV0 is the local variable designating the |
| size of the invariant subspace desired. |
%----------------------------------------------% */
np = *ncv - *nev;
nev0 = *nev;
/* %-----------------------------%
| Zero out internal workspace |
%-----------------------------%
Computing 2nd power */
i__2 = *ncv;
i__1 = i__2 * i__2 + (*ncv << 3);
for (j = 1; j <= i__1; ++j) {
workl[j] = 0.;
/* L10: */
}
/* %-------------------------------------------------------%
| Pointer into WORKL for address of H, RITZ, BOUNDS, Q |
| etc... and the remaining workspace. |
| Also update pointer to be used on output. |
| Memory is laid out as follows: |
| workl(1:2*ncv) := generated tridiagonal matrix |
| workl(2*ncv+1:2*ncv+ncv) := ritz values |
| workl(3*ncv+1:3*ncv+ncv) := computed error bounds |
| workl(4*ncv+1:4*ncv+ncv*ncv) := rotation matrix Q |
| workl(4*ncv+ncv*ncv+1:7*ncv+ncv*ncv) := workspace |
%-------------------------------------------------------% */
ldh = *ncv;
ldq = *ncv;
ih = 1;
ritz = ih + (ldh << 1);
bounds = ritz + *ncv;
iq = bounds + *ncv;
/* Computing 2nd power */
i__1 = *ncv;
iw = iq + i__1 * i__1;
next = iw + *ncv * 3;
ipntr[4] = next;
ipntr[5] = ih;
ipntr[6] = ritz;
ipntr[7] = bounds;
ipntr[11] = iw;
}
/* %-------------------------------------------------------%
| Carry out the Implicitly restarted Lanczos Iteration. |
%-------------------------------------------------------% */
igraphdsaup2_(ido, bmat, n, which, &nev0, &np, tol, &resid[1], &mode, &iupd, &
ishift, &mxiter, &v[v_offset], ldv, &workl[ih], &ldh, &workl[ritz]
, &workl[bounds], &workl[iq], &ldq, &workl[iw], &ipntr[1], &workd[
1], info);
/* %--------------------------------------------------%
| ido .ne. 99 implies use of reverse communication |
| to compute operations involving OP or shifts. |
%--------------------------------------------------% */
if (*ido == 3) {
iparam[8] = np;
}
if (*ido != 99) {
goto L9000;
}
iparam[3] = mxiter;
iparam[5] = np;
iparam[9] = nopx;
iparam[10] = nbx;
iparam[11] = nrorth;
/* %------------------------------------%
| Exit if there was an informational |
| error within dsaup2. |
%------------------------------------% */
if (*info < 0) {
goto L9000;
}
if (*info == 2) {
*info = 3;
}
if (msglvl > 0) {
igraphivout_(&logfil, &c__1, &mxiter, &ndigit, "_saupd: number of update i"
"terations taken", (ftnlen)41);
igraphivout_(&logfil, &c__1, &np, &ndigit, "_saupd: number of \"converge"
"d\" Ritz values", (ftnlen)41);
igraphdvout_(&logfil, &np, &workl[ritz], &ndigit, "_saupd: final Ritz valu"
"es", (ftnlen)25);
igraphdvout_(&logfil, &np, &workl[bounds], &ndigit, "_saupd: corresponding"
" error bounds", (ftnlen)34);
}
igraphsecond_(&t1);
tsaupd = t1 - t0;
if (msglvl > 0) {
/* %--------------------------------------------------------%
| Version Number & Version Date are defined in version.h |
%--------------------------------------------------------% */
s_wsfe(&io___28);
e_wsfe();
s_wsfe(&io___29);
do_fio(&c__1, (char *)&mxiter, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nopx, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nbx, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nrorth, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nitref, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&nrstrt, (ftnlen)sizeof(integer));
do_fio(&c__1, (char *)&tmvopx, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tmvbx, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tsaupd, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tsaup2, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tsaitr, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&titref, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tgetv0, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tseigt, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tsgets, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tsapps, (ftnlen)sizeof(real));
do_fio(&c__1, (char *)&tsconv, (ftnlen)sizeof(real));
e_wsfe();
}
L9000:
return 0;
/* %---------------%
| End of dsaupd |
%---------------% */
} /* igraphdsaupd_ */
/* ----------------------------------------------------------------------- */
/* Subroutine */ int igraphdseupd_(logical *rvec, char *howmny, logical *
select, doublereal *d__, doublereal *z__, integer *ldz, doublereal *
sigma, char *bmat, integer *n, char *which, integer *nev, doublereal *
tol, doublereal *resid, integer *ncv, doublereal *v, integer *ldv,
integer *iparam, integer *ipntr, doublereal *workd, doublereal *workl,
integer *lworkl, integer *info)
{
/* System generated locals */
integer v_dim1, v_offset, z_dim1, z_offset, i__1;
doublereal d__1, d__2, d__3;
/* Builtin functions */
integer igraphs_cmp(char *, char *, ftnlen, ftnlen);
/* Subroutine */ int igraphs_copy(char *, char *, ftnlen, ftnlen);
double igraphpow_dd(doublereal *, doublereal *);
/* Local variables */
static integer j, k, ih, jj, iq, np, iw;
extern /* Subroutine */ int igraphdger_(integer *, integer *, doublereal *
, doublereal *, integer *, doublereal *, integer *, doublereal *,
integer *);
static integer ibd, ihb, ihd, ldh;
extern doublereal igraphdnrm2_(integer *, doublereal *, integer *);
static integer ldq, irz;
extern /* Subroutine */ int igraphdscal_(integer *, doublereal *,
doublereal *, integer *), igraphdcopy_(integer *, doublereal *,
integer *, doublereal *, integer *), igraphdvout_(integer *,
integer *, doublereal *, integer *, char *), igraphivout_(
integer *, integer *, integer *, integer *, char *),
igraphdgeqr2_(integer *, integer *, doublereal *, integer *,
doublereal *, doublereal *, integer *);
static integer mode;
static doublereal eps23;
extern /* Subroutine */ int igraphdorm2r_(char *, char *, integer *,
integer *, integer *, doublereal *, integer *, doublereal *,
doublereal *, integer *, doublereal *, integer *);
static integer ierr;
static doublereal temp;
static integer next;
static char type__[6];
extern doublereal igraphdlamch_(char *);
static integer ritz;
extern /* Subroutine */ int igraphdlacpy_(char *, integer *, integer *,
doublereal *, integer *, doublereal *, integer *),
igraphdsgets_(integer *, char *, integer *, integer *, doublereal
*, doublereal *, doublereal *);
static doublereal temp1;
extern /* Subroutine */ int igraphdsteqr_(char *, integer *, doublereal *,
doublereal *, doublereal *, integer *, doublereal *, integer *), igraphdsesrt_(char *, logical *, integer *, doublereal *,
integer *, doublereal *, integer *), igraphdsortr_(char *
, logical *, integer *, doublereal *, doublereal *);
static logical reord;
static integer nconv;
static doublereal rnorm, bnorm2;
static integer bounds, msglvl, ishift, numcnv, leftptr, rghtptr;
/* %----------------------------------------------------% */
/* | Include files for debugging and timing information | */
/* %----------------------------------------------------% */
/* \SCCS Information: @(#) */
/* FILE: debug.h SID: 2.3 DATE OF SID: 11/16/95 RELEASE: 2 */
/* %---------------------------------% */
/* | See debug.doc for documentation | */
/* %---------------------------------% */
/* %------------------% */
/* | Scalar Arguments | */
/* %------------------% */
/* %--------------------------------% */
/* | See stat.doc for documentation | */
/* %--------------------------------% */
/* \SCCS Information: @(#) */
/* FILE: stat.h SID: 2.2 DATE OF SID: 11/16/95 RELEASE: 2 */
/* %-----------------% */
/* | Array Arguments | */
/* %-----------------% */
/* %------------% */
/* | Parameters | */
/* %------------% */
/* %---------------% */
/* | Local Scalars | */
/* %---------------% */
/* %----------------------% */
/* | External Subroutines | */
/* %----------------------% */
/* %--------------------% */
/* | External Functions | */
/* %--------------------% */
/* %---------------------% */
/* | Intrinsic Functions | */
/* %---------------------% */
/* %-----------------------% */
/* | Executable Statements | */
/* %-----------------------% */
/* %------------------------% */
/* | Set default parameters | */
/* %------------------------% */
/* Parameter adjustments */
--workd;
--resid;
z_dim1 = *ldz;
z_offset = 1 + z_dim1;
z__ -= z_offset;
--d__;
--select;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
--iparam;
--ipntr;
--workl;
/* Function Body */
msglvl = debug_1.mseupd;
mode = iparam[7];
nconv = iparam[5];
*info = 0;
/* %--------------% */
/* | Quick return | */
/* %--------------% */
if (nconv == 0) {
goto L9000;
}
ierr = 0;
if (nconv <= 0) {
ierr = -14;
}
if (*n <= 0) {
ierr = -1;
}
if (*nev <= 0) {
ierr = -2;
}
if (*ncv <= *nev || *ncv > *n) {
ierr = -3;
}
if (igraphs_cmp(which, "LM", (ftnlen)2, (ftnlen)2) != 0 && igraphs_cmp(which, "SM", (
ftnlen)2, (ftnlen)2) != 0 && igraphs_cmp(which, "LA", (ftnlen)2, (
ftnlen)2) != 0 && igraphs_cmp(which, "SA", (ftnlen)2, (ftnlen)2) != 0 &&
igraphs_cmp(which, "BE", (ftnlen)2, (ftnlen)2) != 0) {
ierr = -5;
}
if (*(unsigned char *)bmat != 'I' && *(unsigned char *)bmat != 'G') {
ierr = -6;
}
if (*(unsigned char *)howmny != 'A' && *(unsigned char *)howmny != 'P' &&
*(unsigned char *)howmny != 'S' && *rvec) {
ierr = -15;
}
if (*rvec && *(unsigned char *)howmny == 'S') {
ierr = -16;
}
/* Computing 2nd power */
i__1 = *ncv;
if (*rvec && *lworkl < i__1 * i__1 + (*ncv << 3)) {
ierr = -7;
}
if (mode == 1 || mode == 2) {
igraphs_copy(type__, "REGULR", (ftnlen)6, (ftnlen)6);
} else if (mode == 3) {
igraphs_copy(type__, "SHIFTI", (ftnlen)6, (ftnlen)6);
} else if (mode == 4) {
igraphs_copy(type__, "BUCKLE", (ftnlen)6, (ftnlen)6);
} else if (mode == 5) {
igraphs_copy(type__, "CAYLEY", (ftnlen)6, (ftnlen)6);
} else {
ierr = -10;
}
if (mode == 1 && *(unsigned char *)bmat == 'G') {
ierr = -11;
}
if (*nev == 1 && igraphs_cmp(which, "BE", (ftnlen)2, (ftnlen)2) == 0) {
ierr = -12;
}
/* %------------% */
/* | Error Exit | */
/* %------------% */
if (ierr != 0) {
*info = ierr;
goto L9000;
}
/* %-------------------------------------------------------% */
/* | Pointer into WORKL for address of H, RITZ, BOUNDS, Q | */
/* | etc... and the remaining workspace. | */
/* | Also update pointer to be used on output. | */
/* | Memory is laid out as follows: | */
/* | workl(1:2*ncv) := generated tridiagonal matrix H | */
/* | The subdiagonal is stored in workl(2:ncv). | */
/* | The dead spot is workl(1) but upon exiting | */
/* | dsaupd stores the B-norm of the last residual | */
/* | vector in workl(1). We use this !!! | */
/* | workl(2*ncv+1:2*ncv+ncv) := ritz values | */
/* | The wanted values are in the first NCONV spots. | */
/* | workl(3*ncv+1:3*ncv+ncv) := computed Ritz estimates | */
/* | The wanted values are in the first NCONV spots. | */
/* | NOTE: workl(1:4*ncv) is set by dsaupd and is not | */
/* | modified by dseupd . | */
/* %-------------------------------------------------------% */
/* %-------------------------------------------------------% */
/* | The following is used and set by dseupd . | */
/* | workl(4*ncv+1:4*ncv+ncv) := used as workspace during | */
/* | computation of the eigenvectors of H. Stores | */
/* | the diagonal of H. Upon EXIT contains the NCV | */
/* | Ritz values of the original system. The first | */
/* | NCONV spots have the wanted values. If MODE = | */
/* | 1 or 2 then will equal workl(2*ncv+1:3*ncv). | */
/* | workl(5*ncv+1:5*ncv+ncv) := used as workspace during | */
/* | computation of the eigenvectors of H. Stores | */
/* | the subdiagonal of H. Upon EXIT contains the | */
/* | NCV corresponding Ritz estimates of the | */
/* | original system. The first NCONV spots have the | */
/* | wanted values. If MODE = 1,2 then will equal | */
/* | workl(3*ncv+1:4*ncv). | */
/* | workl(6*ncv+1:6*ncv+ncv*ncv) := orthogonal Q that is | */
/* | the eigenvector matrix for H as returned by | */
/* | dsteqr . Not referenced if RVEC = .False. | */
/* | Ordering follows that of workl(4*ncv+1:5*ncv) | */
/* | workl(6*ncv+ncv*ncv+1:6*ncv+ncv*ncv+2*ncv) := | */
/* | Workspace. Needed by dsteqr and by dseupd . | */
/* | GRAND total of NCV*(NCV+8) locations. | */
/* %-------------------------------------------------------% */
ih = ipntr[5];
ritz = ipntr[6];
bounds = ipntr[7];
ldh = *ncv;
ldq = *ncv;
ihd = bounds + ldh;
ihb = ihd + ldh;
iq = ihb + ldh;
iw = iq + ldh * *ncv;
next = iw + (*ncv << 1);
ipntr[4] = next;
ipntr[8] = ihd;
ipntr[9] = ihb;
ipntr[10] = iq;
/* %----------------------------------------% */
/* | irz points to the Ritz values computed | */
/* | by _seigt before exiting _saup2. | */
/* | ibd points to the Ritz estimates | */
/* | computed by _seigt before exiting | */
/* | _saup2. | */
/* %----------------------------------------% */
irz = ipntr[11] + *ncv;
ibd = irz + *ncv;
/* %---------------------------------% */
/* | Set machine dependent constant. | */
/* %---------------------------------% */
eps23 = igraphdlamch_("Epsilon-Machine");
eps23 = igraphpow_dd(&eps23, &c_b21);
/* %---------------------------------------% */
/* | RNORM is B-norm of the RESID(1:N). | */
/* | BNORM2 is the 2 norm of B*RESID(1:N). | */
/* | Upon exit of dsaupd WORKD(1:N) has | */
/* | B*RESID(1:N). | */
/* %---------------------------------------% */
rnorm = workl[ih];
if (*(unsigned char *)bmat == 'I') {
bnorm2 = rnorm;
} else if (*(unsigned char *)bmat == 'G') {
bnorm2 = igraphdnrm2_(n, &workd[1], &c__1);
}
if (msglvl > 2) {
igraphdvout_(&debug_1.logfil, ncv, &workl[irz], &debug_1.ndigit,
"_seupd: Ritz values passed in from _SAUPD.");
igraphdvout_(&debug_1.logfil, ncv, &workl[ibd], &debug_1.ndigit,
"_seupd: Ritz estimates passed in from _SAUPD.");
}
if (*rvec) {
reord = FALSE_;
/* %---------------------------------------------------% */
/* | Use the temporary bounds array to store indices | */
/* | These will be used to mark the select array later | */
/* %---------------------------------------------------% */
i__1 = *ncv;
for (j = 1; j <= i__1; ++j) {
workl[bounds + j - 1] = (doublereal) j;
select[j] = FALSE_;
/* L10: */
}
/* %-------------------------------------% */
/* | Select the wanted Ritz values. | */
/* | Sort the Ritz values so that the | */
/* | wanted ones appear at the tailing | */
/* | NEV positions of workl(irr) and | */
/* | workl(iri). Move the corresponding | */
/* | error estimates in workl(bound) | */
/* | accordingly. | */
/* %-------------------------------------% */
np = *ncv - *nev;
ishift = 0;
igraphdsgets_(&ishift, which, nev, &np, &workl[irz], &workl[bounds], &
workl[1]);
if (msglvl > 2) {
igraphdvout_(&debug_1.logfil, ncv, &workl[irz], &debug_1.ndigit,
"_seupd: Ritz values after calling _SGETS.");
igraphdvout_(&debug_1.logfil, ncv, &workl[bounds], &
debug_1.ndigit, "_seupd: Ritz value indices after callin"
"g _SGETS.");
}
/* %-----------------------------------------------------% */
/* | Record indices of the converged wanted Ritz values | */
/* | Mark the select array for possible reordering | */
/* %-----------------------------------------------------% */
numcnv = 0;
i__1 = *ncv;
for (j = 1; j <= i__1; ++j) {
/* Computing MAX */
d__2 = eps23, d__3 = (d__1 = workl[irz + *ncv - j], abs(d__1));
temp1 = max(d__2,d__3);
jj = (integer) workl[bounds + *ncv - j];
if (numcnv < nconv && workl[ibd + jj - 1] <= *tol * temp1) {
select[jj] = TRUE_;
++numcnv;
if (jj > *nev) {
reord = TRUE_;
}
}
/* L11: */
}
/* %-----------------------------------------------------------% */
/* | Check the count (numcnv) of converged Ritz values with | */
/* | the number (nconv) reported by _saupd. If these two | */
/* | are different then there has probably been an error | */
/* | caused by incorrect passing of the _saupd data. | */
/* %-----------------------------------------------------------% */
if (msglvl > 2) {
igraphivout_(&debug_1.logfil, &c__1, &numcnv, &debug_1.ndigit,
"_seupd: Number of specified eigenvalues");
igraphivout_(&debug_1.logfil, &c__1, &nconv, &debug_1.ndigit,
"_seupd: Number of \"converged\" eigenvalues")
;
}
if (numcnv != nconv) {
*info = -17;
goto L9000;
}
/* %-----------------------------------------------------------% */
/* | Call LAPACK routine _steqr to compute the eigenvalues and | */
/* | eigenvectors of the final symmetric tridiagonal matrix H. | */
/* | Initialize the eigenvector matrix Q to the identity. | */
/* %-----------------------------------------------------------% */
i__1 = *ncv - 1;
igraphdcopy_(&i__1, &workl[ih + 1], &c__1, &workl[ihb], &c__1);
igraphdcopy_(ncv, &workl[ih + ldh], &c__1, &workl[ihd], &c__1);
igraphdsteqr_("Identity", ncv, &workl[ihd], &workl[ihb], &workl[iq], &
ldq, &workl[iw], &ierr);
if (ierr != 0) {
*info = -8;
goto L9000;
}
if (msglvl > 1) {
igraphdcopy_(ncv, &workl[iq + *ncv - 1], &ldq, &workl[iw], &c__1);
igraphdvout_(&debug_1.logfil, ncv, &workl[ihd], &debug_1.ndigit,
"_seupd: NCV Ritz values of the final H matrix");
igraphdvout_(&debug_1.logfil, ncv, &workl[iw], &debug_1.ndigit,
"_seupd: last row of the eigenvector matrix for H");
}
if (reord) {
/* %---------------------------------------------% */
/* | Reordered the eigenvalues and eigenvectors | */
/* | computed by _steqr so that the "converged" | */
/* | eigenvalues appear in the first NCONV | */
/* | positions of workl(ihd), and the associated | */
/* | eigenvectors appear in the first NCONV | */
/* | columns. | */
/* %---------------------------------------------% */
leftptr = 1;
rghtptr = *ncv;
if (*ncv == 1) {
goto L30;
}
L20:
if (select[leftptr]) {
/* %-------------------------------------------% */
/* | Search, from the left, for the first Ritz | */
/* | value that has not converged. | */
/* %-------------------------------------------% */
++leftptr;
} else if (! select[rghtptr]) {
/* %----------------------------------------------% */
/* | Search, from the right, the first Ritz value | */
/* | that has converged. | */
/* %----------------------------------------------% */
--rghtptr;
} else {
/* %----------------------------------------------% */
/* | Swap the Ritz value on the left that has not | */
/* | converged with the Ritz value on the right | */
/* | that has converged. Swap the associated | */
/* | eigenvector of the tridiagonal matrix H as | */
/* | well. | */
/* %----------------------------------------------% */
temp = workl[ihd + leftptr - 1];
workl[ihd + leftptr - 1] = workl[ihd + rghtptr - 1];
workl[ihd + rghtptr - 1] = temp;
igraphdcopy_(ncv, &workl[iq + *ncv * (leftptr - 1)], &c__1, &
workl[iw], &c__1);
igraphdcopy_(ncv, &workl[iq + *ncv * (rghtptr - 1)], &c__1, &
workl[iq + *ncv * (leftptr - 1)], &c__1);
igraphdcopy_(ncv, &workl[iw], &c__1, &workl[iq + *ncv * (
rghtptr - 1)], &c__1);
++leftptr;
--rghtptr;
}
if (leftptr < rghtptr) {
goto L20;
}
L30:
;
}
if (msglvl > 2) {
igraphdvout_(&debug_1.logfil, ncv, &workl[ihd], &debug_1.ndigit,
"_seupd: The eigenvalues of H--reordered");
}
/* %----------------------------------------% */
/* | Load the converged Ritz values into D. | */
/* %----------------------------------------% */
igraphdcopy_(&nconv, &workl[ihd], &c__1, &d__[1], &c__1);
} else {
/* %-----------------------------------------------------% */
/* | Ritz vectors not required. Load Ritz values into D. | */
/* %-----------------------------------------------------% */
igraphdcopy_(&nconv, &workl[ritz], &c__1, &d__[1], &c__1);
igraphdcopy_(ncv, &workl[ritz], &c__1, &workl[ihd], &c__1);
}
/* %------------------------------------------------------------------% */
/* | Transform the Ritz values and possibly vectors and corresponding | */
/* | Ritz estimates of OP to those of A*x=lambda*B*x. The Ritz values | */
/* | (and corresponding data) are returned in ascending order. | */
/* %------------------------------------------------------------------% */
if (igraphs_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) == 0) {
/* %---------------------------------------------------------% */
/* | Ascending sort of wanted Ritz values, vectors and error | */
/* | bounds. Not necessary if only Ritz values are desired. | */
/* %---------------------------------------------------------% */
if (*rvec) {
igraphdsesrt_("LA", rvec, &nconv, &d__[1], ncv, &workl[iq], &ldq);
} else {
igraphdcopy_(ncv, &workl[bounds], &c__1, &workl[ihb], &c__1);
}
} else {
/* %-------------------------------------------------------------% */
/* | * Make a copy of all the Ritz values. | */
/* | * Transform the Ritz values back to the original system. | */
/* | For TYPE = 'SHIFTI' the transformation is | */
/* | lambda = 1/theta + sigma | */
/* | For TYPE = 'BUCKLE' the transformation is | */
/* | lambda = sigma * theta / ( theta - 1 ) | */
/* | For TYPE = 'CAYLEY' the transformation is | */
/* | lambda = sigma * (theta + 1) / (theta - 1 ) | */
/* | where the theta are the Ritz values returned by dsaupd . | */
/* | NOTES: | */
/* | *The Ritz vectors are not affected by the transformation. | */
/* | They are only reordered. | */
/* %-------------------------------------------------------------% */
igraphdcopy_(ncv, &workl[ihd], &c__1, &workl[iw], &c__1);
if (igraphs_cmp(type__, "SHIFTI", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
workl[ihd + k - 1] = 1. / workl[ihd + k - 1] + *sigma;
/* L40: */
}
} else if (igraphs_cmp(type__, "BUCKLE", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
workl[ihd + k - 1] = *sigma * workl[ihd + k - 1] / (workl[ihd
+ k - 1] - 1.);
/* L50: */
}
} else if (igraphs_cmp(type__, "CAYLEY", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
workl[ihd + k - 1] = *sigma * (workl[ihd + k - 1] + 1.) / (
workl[ihd + k - 1] - 1.);
/* L60: */
}
}
/* %-------------------------------------------------------------% */
/* | * Store the wanted NCONV lambda values into D. | */
/* | * Sort the NCONV wanted lambda in WORKL(IHD:IHD+NCONV-1) | */
/* | into ascending order and apply sort to the NCONV theta | */
/* | values in the transformed system. We will need this to | */
/* | compute Ritz estimates in the original system. | */
/* | * Finally sort the lambda`s into ascending order and apply | */
/* | to Ritz vectors if wanted. Else just sort lambda`s into | */
/* | ascending order. | */
/* | NOTES: | */
/* | *workl(iw:iw+ncv-1) contain the theta ordered so that they | */
/* | match the ordering of the lambda. We`ll use them again for | */
/* | Ritz vector purification. | */
/* %-------------------------------------------------------------% */
igraphdcopy_(&nconv, &workl[ihd], &c__1, &d__[1], &c__1);
igraphdsortr_("LA", &c_true, &nconv, &workl[ihd], &workl[iw]);
if (*rvec) {
igraphdsesrt_("LA", rvec, &nconv, &d__[1], ncv, &workl[iq], &ldq);
} else {
igraphdcopy_(ncv, &workl[bounds], &c__1, &workl[ihb], &c__1);
d__1 = bnorm2 / rnorm;
igraphdscal_(ncv, &d__1, &workl[ihb], &c__1);
igraphdsortr_("LA", &c_true, &nconv, &d__[1], &workl[ihb]);
}
}
/* %------------------------------------------------% */
/* | Compute the Ritz vectors. Transform the wanted | */
/* | eigenvectors of the symmetric tridiagonal H by | */
/* | the Lanczos basis matrix V. | */
/* %------------------------------------------------% */
if (*rvec && *(unsigned char *)howmny == 'A') {
/* %----------------------------------------------------------% */
/* | Compute the QR factorization of the matrix representing | */
/* | the wanted invariant subspace located in the first NCONV | */
/* | columns of workl(iq,ldq). | */
/* %----------------------------------------------------------% */
igraphdgeqr2_(ncv, &nconv, &workl[iq], &ldq, &workl[iw + *ncv], &
workl[ihb], &ierr);
/* %--------------------------------------------------------% */
/* | * Postmultiply V by Q. | */
/* | * Copy the first NCONV columns of VQ into Z. | */
/* | The N by NCONV matrix Z is now a matrix representation | */
/* | of the approximate invariant subspace associated with | */
/* | the Ritz values in workl(ihd). | */
/* %--------------------------------------------------------% */
igraphdorm2r_("Right", "Notranspose", n, ncv, &nconv, &workl[iq], &
ldq, &workl[iw + *ncv], &v[v_offset], ldv, &workd[*n + 1], &
ierr);
igraphdlacpy_("All", n, &nconv, &v[v_offset], ldv, &z__[z_offset],
ldz);
/* %-----------------------------------------------------% */
/* | In order to compute the Ritz estimates for the Ritz | */
/* | values in both systems, need the last row of the | */
/* | eigenvector matrix. Remember, it`s in factored form | */
/* %-----------------------------------------------------% */
i__1 = *ncv - 1;
for (j = 1; j <= i__1; ++j) {
workl[ihb + j - 1] = 0.;
/* L65: */
}
workl[ihb + *ncv - 1] = 1.;
igraphdorm2r_("Left", "Transpose", ncv, &c__1, &nconv, &workl[iq], &
ldq, &workl[iw + *ncv], &workl[ihb], ncv, &temp, &ierr);
} else if (*rvec && *(unsigned char *)howmny == 'S') {
/* Not yet implemented. See remark 2 above. */
}
if (igraphs_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) == 0 && *rvec) {
i__1 = *ncv;
for (j = 1; j <= i__1; ++j) {
workl[ihb + j - 1] = rnorm * (d__1 = workl[ihb + j - 1], abs(d__1)
);
/* L70: */
}
} else if (igraphs_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) != 0 && *rvec) {
/* %-------------------------------------------------% */
/* | * Determine Ritz estimates of the theta. | */
/* | If RVEC = .true. then compute Ritz estimates | */
/* | of the theta. | */
/* | If RVEC = .false. then copy Ritz estimates | */
/* | as computed by dsaupd . | */
/* | * Determine Ritz estimates of the lambda. | */
/* %-------------------------------------------------% */
igraphdscal_(ncv, &bnorm2, &workl[ihb], &c__1);
if (igraphs_cmp(type__, "SHIFTI", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
/* Computing 2nd power */
d__2 = workl[iw + k - 1];
workl[ihb + k - 1] = (d__1 = workl[ihb + k - 1], abs(d__1)) /
(d__2 * d__2);
/* L80: */
}
} else if (igraphs_cmp(type__, "BUCKLE", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
/* Computing 2nd power */
d__2 = workl[iw + k - 1] - 1.;
workl[ihb + k - 1] = *sigma * (d__1 = workl[ihb + k - 1], abs(
d__1)) / (d__2 * d__2);
/* L90: */
}
} else if (igraphs_cmp(type__, "CAYLEY", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
workl[ihb + k - 1] = (d__1 = workl[ihb + k - 1] / workl[iw +
k - 1] * (workl[iw + k - 1] - 1.), abs(d__1));
/* L100: */
}
}
}
if (igraphs_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) != 0 && msglvl > 1) {
igraphdvout_(&debug_1.logfil, &nconv, &d__[1], &debug_1.ndigit, "_se"
"upd: Untransformed converged Ritz values");
igraphdvout_(&debug_1.logfil, &nconv, &workl[ihb], &debug_1.ndigit,
"_seupd: Ritz estimates of the untransformed Ritz values");
} else if (msglvl > 1) {
igraphdvout_(&debug_1.logfil, &nconv, &d__[1], &debug_1.ndigit, "_se"
"upd: Converged Ritz values");
igraphdvout_(&debug_1.logfil, &nconv, &workl[ihb], &debug_1.ndigit,
"_seupd: Associated Ritz estimates");
}
/* %-------------------------------------------------% */
/* | Ritz vector purification step. Formally perform | */
/* | one of inverse subspace iteration. Only used | */
/* | for MODE = 3,4,5. See reference 7 | */
/* %-------------------------------------------------% */
if (*rvec && (igraphs_cmp(type__, "SHIFTI", (ftnlen)6, (ftnlen)6) == 0 || igraphs_cmp(
type__, "CAYLEY", (ftnlen)6, (ftnlen)6) == 0)) {
i__1 = nconv - 1;
for (k = 0; k <= i__1; ++k) {
workl[iw + k] = workl[iq + k * ldq + *ncv - 1] / workl[iw + k];
/* L110: */
}
} else if (*rvec && igraphs_cmp(type__, "BUCKLE", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = nconv - 1;
for (k = 0; k <= i__1; ++k) {
workl[iw + k] = workl[iq + k * ldq + *ncv - 1] / (workl[iw + k] -
1.);
/* L120: */
}
}
if (igraphs_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) != 0) {
igraphdger_(n, &nconv, &c_b110, &resid[1], &c__1, &workl[iw], &c__1, &
z__[z_offset], ldz);
}
L9000:
return 0;
/* %---------------% */
/* | End of dseupd | */
/* %---------------% */
} /* igraphdseupd_ */
Subroutine */ int igraphdseupd_(logical *rvec, char *howmny, logical *select,
doublereal *d__, doublereal *z__, integer *ldz, doublereal *sigma,
char *bmat, integer *n, char *which, integer *nev, doublereal *tol,
doublereal *resid, integer *ncv, doublereal *v, integer *ldv, integer
*iparam, integer *ipntr, doublereal *workd, doublereal *workl,
integer *lworkl, integer *info)
{
/* System generated locals */
integer v_dim1, v_offset, z_dim1, z_offset, i__1;
doublereal d__1, d__2, d__3;
/* Builtin functions */
integer s_cmp(char *, char *, ftnlen, ftnlen);
/* Subroutine */ int s_copy(char *, char *, ftnlen, ftnlen);
double pow_dd(doublereal *, doublereal *);
/* Local variables */
integer j, k, ih, iq, iw;
doublereal kv[2];
integer ibd, ihb, ihd, ldh, ilg, ldq, ism, irz;
extern /* Subroutine */ int igraphdger_(integer *, integer *, doublereal *,
doublereal *, integer *, doublereal *, integer *, doublereal *,
integer *);
integer mode;
doublereal eps23;
integer ierr;
doublereal temp;
integer next;
char type__[6];
integer ritz;
extern doublereal igraphdnrm2_(integer *, doublereal *, integer *);
extern /* Subroutine */ int igraphdscal_(integer *, doublereal *, doublereal *,
integer *);
logical reord;
extern /* Subroutine */ int igraphdcopy_(integer *, doublereal *, integer *,
doublereal *, integer *);
integer nconv;
doublereal rnorm;
extern /* Subroutine */ int igraphdvout_(integer *, integer *, doublereal *,
integer *, char *, ftnlen), igraphivout_(integer *, integer *, integer *
, integer *, char *, ftnlen), igraphdgeqr2_(integer *, integer *,
doublereal *, integer *, doublereal *, doublereal *, integer *);
doublereal bnorm2;
extern /* Subroutine */ int igraphdorm2r_(char *, char *, integer *, integer *,
integer *, doublereal *, integer *, doublereal *, doublereal *,
integer *, doublereal *, integer *);
doublereal thres1, thres2;
extern doublereal igraphdlamch_(char *);
extern /* Subroutine */ int igraphdlacpy_(char *, integer *, integer *,
doublereal *, integer *, doublereal *, integer *);
integer logfil, ndigit, bounds, mseupd = 0;
extern /* Subroutine */ int igraphdsteqr_(char *, integer *, doublereal *,
doublereal *, doublereal *, integer *, doublereal *, integer *);
integer msglvl, ktrord;
extern /* Subroutine */ int igraphdsesrt_(char *, logical *, integer *,
doublereal *, integer *, doublereal *, integer *),
igraphdsortr_(char *, logical *, integer *, doublereal *, doublereal *);
doublereal tempbnd;
integer leftptr, rghtptr;
/* %----------------------------------------------------%
| Include files for debugging and timing information |
%----------------------------------------------------%
%------------------%
| Scalar Arguments |
%------------------%
%-----------------%
| Array Arguments |
%-----------------%
%------------%
| Parameters |
%------------%
%---------------%
| Local Scalars |
%---------------%
%--------------%
| Local Arrays |
%--------------%
%----------------------%
| External Subroutines |
%----------------------%
%--------------------%
| External Functions |
%--------------------%
%---------------------%
| Intrinsic Functions |
%---------------------%
%-----------------------%
| Executable Statements |
%-----------------------%
%------------------------%
| Set default parameters |
%------------------------%
Parameter adjustments */
--workd;
--resid;
z_dim1 = *ldz;
z_offset = 1 + z_dim1;
z__ -= z_offset;
--d__;
--select;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
--iparam;
--ipntr;
--workl;
/* Function Body */
msglvl = mseupd;
mode = iparam[7];
nconv = iparam[5];
*info = 0;
/* %--------------%
| Quick return |
%--------------% */
if (nconv == 0) {
goto L9000;
}
ierr = 0;
if (nconv <= 0) {
ierr = -14;
}
if (*n <= 0) {
ierr = -1;
}
if (*nev <= 0) {
ierr = -2;
}
if (*ncv <= *nev || *ncv > *n) {
ierr = -3;
}
if (s_cmp(which, "LM", (ftnlen)2, (ftnlen)2) != 0 && s_cmp(which, "SM", (
ftnlen)2, (ftnlen)2) != 0 && s_cmp(which, "LA", (ftnlen)2, (
ftnlen)2) != 0 && s_cmp(which, "SA", (ftnlen)2, (ftnlen)2) != 0 &&
s_cmp(which, "BE", (ftnlen)2, (ftnlen)2) != 0) {
ierr = -5;
}
if (*(unsigned char *)bmat != 'I' && *(unsigned char *)bmat != 'G') {
ierr = -6;
}
if (*(unsigned char *)howmny != 'A' && *(unsigned char *)howmny != 'P' &&
*(unsigned char *)howmny != 'S' && *rvec) {
ierr = -15;
}
if (*rvec && *(unsigned char *)howmny == 'S') {
ierr = -16;
}
/* Computing 2nd power */
i__1 = *ncv;
if (*rvec && *lworkl < i__1 * i__1 + (*ncv << 3)) {
ierr = -7;
}
if (mode == 1 || mode == 2) {
s_copy(type__, "REGULR", (ftnlen)6, (ftnlen)6);
} else if (mode == 3) {
s_copy(type__, "SHIFTI", (ftnlen)6, (ftnlen)6);
} else if (mode == 4) {
s_copy(type__, "BUCKLE", (ftnlen)6, (ftnlen)6);
} else if (mode == 5) {
s_copy(type__, "CAYLEY", (ftnlen)6, (ftnlen)6);
} else {
ierr = -10;
}
if (mode == 1 && *(unsigned char *)bmat == 'G') {
ierr = -11;
}
if (*nev == 1 && s_cmp(which, "BE", (ftnlen)2, (ftnlen)2) == 0) {
ierr = -12;
}
/* %------------%
| Error Exit |
%------------% */
if (ierr != 0) {
*info = ierr;
goto L9000;
}
/* %-------------------------------------------------------%
| Pointer into WORKL for address of H, RITZ, BOUNDS, Q |
| etc... and the remaining workspace. |
| Also update pointer to be used on output. |
| Memory is laid out as follows: |
| workl(1:2*ncv) := generated tridiagonal matrix H |
| The subdiagonal is stored in workl(2:ncv). |
| The dead spot is workl(1) but upon exiting |
| dsaupd stores the B-norm of the last residual |
| vector in workl(1). We use this !!! |
| workl(2*ncv+1:2*ncv+ncv) := ritz values |
| The wanted values are in the first NCONV spots. |
| workl(3*ncv+1:3*ncv+ncv) := computed Ritz estimates |
| The wanted values are in the first NCONV spots. |
| NOTE: workl(1:4*ncv) is set by dsaupd and is not |
| modified by dseupd. |
%-------------------------------------------------------%
%-------------------------------------------------------%
| The following is used and set by dseupd. |
| workl(4*ncv+1:4*ncv+ncv) := used as workspace during |
| computation of the eigenvectors of H. Stores |
| the diagonal of H. Upon EXIT contains the NCV |
| Ritz values of the original system. The first |
| NCONV spots have the wanted values. If MODE = |
| 1 or 2 then will equal workl(2*ncv+1:3*ncv). |
| workl(5*ncv+1:5*ncv+ncv) := used as workspace during |
| computation of the eigenvectors of H. Stores |
| the subdiagonal of H. Upon EXIT contains the |
| NCV corresponding Ritz estimates of the |
| original system. The first NCONV spots have the |
| wanted values. If MODE = 1,2 then will equal |
| workl(3*ncv+1:4*ncv). |
| workl(6*ncv+1:6*ncv+ncv*ncv) := orthogonal Q that is |
| the eigenvector matrix for H as returned by |
| dsteqr. Not referenced if RVEC = .False. |
| Ordering follows that of workl(4*ncv+1:5*ncv) |
| workl(6*ncv+ncv*ncv+1:6*ncv+ncv*ncv+2*ncv) := |
| Workspace. Needed by dsteqr and by dseupd. |
| GRAND total of NCV*(NCV+8) locations. |
%-------------------------------------------------------% */
ih = ipntr[5];
ritz = ipntr[6];
bounds = ipntr[7];
ldh = *ncv;
ldq = *ncv;
ihd = bounds + ldh;
ihb = ihd + ldh;
iq = ihb + ldh;
iw = iq + ldh * *ncv;
next = iw + (*ncv << 1);
ipntr[4] = next;
ipntr[8] = ihd;
ipntr[9] = ihb;
ipntr[10] = iq;
/* %----------------------------------------%
| irz points to the Ritz values computed |
| by _seigt before exiting _saup2. |
| ibd points to the Ritz estimates |
| computed by _seigt before exiting |
| _saup2. |
%----------------------------------------% */
irz = ipntr[11] + *ncv;
ibd = irz + *ncv;
/* %---------------------------------%
| Set machine dependent constant. |
%---------------------------------% */
eps23 = igraphdlamch_("Epsilon-Machine");
eps23 = pow_dd(&eps23, &c_b21);
/* %---------------------------------------%
| RNORM is B-norm of the RESID(1:N). |
| BNORM2 is the 2 norm of B*RESID(1:N). |
| Upon exit of dsaupd WORKD(1:N) has |
| B*RESID(1:N). |
%---------------------------------------% */
rnorm = workl[ih];
if (*(unsigned char *)bmat == 'I') {
bnorm2 = rnorm;
} else if (*(unsigned char *)bmat == 'G') {
bnorm2 = igraphdnrm2_(n, &workd[1], &c__1);
}
if (*rvec) {
/* %------------------------------------------------%
| Get the converged Ritz value on the boundary. |
| This value will be used to dermine whether we |
| need to reorder the eigenvalues and |
| eigenvectors comupted by _steqr, and is |
| referred to as the "threshold" value. |
| |
| A Ritz value gamma is said to be a wanted |
| one, if |
| abs(gamma) .ge. threshold, when WHICH = 'LM'; |
| abs(gamma) .le. threshold, when WHICH = 'SM'; |
| gamma .ge. threshold, when WHICH = 'LA'; |
| gamma .le. threshold, when WHICH = 'SA'; |
| gamma .le. thres1 .or. gamma .ge. thres2 |
| when WHICH = 'BE'; |
| |
| Note: converged Ritz values and associated |
| Ritz estimates have been placed in the first |
| NCONV locations in workl(ritz) and |
| workl(bounds) respectively. They have been |
| sorted (in _saup2) according to the WHICH |
| selection criterion. (Except in the case |
| WHICH = 'BE', they are sorted in an increasing |
| order.) |
%------------------------------------------------% */
if (s_cmp(which, "LM", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(which,
"SM", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(which, "LA", (
ftnlen)2, (ftnlen)2) == 0 || s_cmp(which, "SA", (ftnlen)2, (
ftnlen)2) == 0) {
thres1 = workl[ritz];
if (msglvl > 2) {
igraphdvout_(&logfil, &c__1, &thres1, &ndigit, "_seupd: Threshold "
"eigenvalue used for re-ordering", (ftnlen)49);
}
} else if (s_cmp(which, "BE", (ftnlen)2, (ftnlen)2) == 0) {
/* %------------------------------------------------%
| Ritz values returned from _saup2 have been |
| sorted in increasing order. Thus two |
| "threshold" values (one for the small end, one |
| for the large end) are in the middle. |
%------------------------------------------------% */
ism = max(*nev,nconv) / 2;
ilg = ism + 1;
thres1 = workl[ism];
thres2 = workl[ilg];
if (msglvl > 2) {
kv[0] = thres1;
kv[1] = thres2;
igraphdvout_(&logfil, &c__2, kv, &ndigit, "_seupd: Threshold eigen"
"values used for re-ordering", (ftnlen)50);
}
}
/* %----------------------------------------------------------%
| Check to see if all converged Ritz values appear within |
| the first NCONV diagonal elements returned from _seigt. |
| This is done in the following way: |
| |
| 1) For each Ritz value obtained from _seigt, compare it |
| with the threshold Ritz value computed above to |
| determine whether it is a wanted one. |
| |
| 2) If it is wanted, then check the corresponding Ritz |
| estimate to see if it has converged. If it has, set |
| correponding entry in the logical array SELECT to |
| .TRUE.. |
| |
| If SELECT(j) = .TRUE. and j > NCONV, then there is a |
| converged Ritz value that does not appear at the top of |
| the diagonal matrix computed by _seigt in _saup2. |
| Reordering is needed. |
%----------------------------------------------------------% */
reord = FALSE_;
ktrord = 0;
i__1 = *ncv - 1;
for (j = 0; j <= i__1; ++j) {
select[j + 1] = FALSE_;
if (s_cmp(which, "LM", (ftnlen)2, (ftnlen)2) == 0) {
if ((d__1 = workl[irz + j], abs(d__1)) >= abs(thres1)) {
/* Computing MAX */
d__2 = eps23, d__3 = (d__1 = workl[irz + j], abs(d__1));
tempbnd = max(d__2,d__3);
if (workl[ibd + j] <= *tol * tempbnd) {
select[j + 1] = TRUE_;
}
}
} else if (s_cmp(which, "SM", (ftnlen)2, (ftnlen)2) == 0) {
if ((d__1 = workl[irz + j], abs(d__1)) <= abs(thres1)) {
/* Computing MAX */
d__2 = eps23, d__3 = (d__1 = workl[irz + j], abs(d__1));
tempbnd = max(d__2,d__3);
if (workl[ibd + j] <= *tol * tempbnd) {
select[j + 1] = TRUE_;
}
}
} else if (s_cmp(which, "LA", (ftnlen)2, (ftnlen)2) == 0) {
if (workl[irz + j] >= thres1) {
/* Computing MAX */
d__2 = eps23, d__3 = (d__1 = workl[irz + j], abs(d__1));
tempbnd = max(d__2,d__3);
if (workl[ibd + j] <= *tol * tempbnd) {
select[j + 1] = TRUE_;
}
}
} else if (s_cmp(which, "SA", (ftnlen)2, (ftnlen)2) == 0) {
if (workl[irz + j] <= thres1) {
/* Computing MAX */
d__2 = eps23, d__3 = (d__1 = workl[irz + j], abs(d__1));
tempbnd = max(d__2,d__3);
if (workl[ibd + j] <= *tol * tempbnd) {
select[j + 1] = TRUE_;
}
}
} else if (s_cmp(which, "BE", (ftnlen)2, (ftnlen)2) == 0) {
if (workl[irz + j] <= thres1 || workl[irz + j] >= thres2) {
/* Computing MAX */
d__2 = eps23, d__3 = (d__1 = workl[irz + j], abs(d__1));
tempbnd = max(d__2,d__3);
if (workl[ibd + j] <= *tol * tempbnd) {
select[j + 1] = TRUE_;
}
}
}
if (j + 1 > nconv) {
reord = select[j + 1] || reord;
}
if (select[j + 1]) {
++ktrord;
}
/* L10: */
}
/* %-------------------------------------------%
| If KTRORD .ne. NCONV, something is wrong. |
%-------------------------------------------% */
if (msglvl > 2) {
igraphivout_(&logfil, &c__1, &ktrord, &ndigit, "_seupd: Number of spec"
"ified eigenvalues", (ftnlen)39);
igraphivout_(&logfil, &c__1, &nconv, &ndigit, "_seupd: Number of \"con"
"verged\" eigenvalues", (ftnlen)41);
}
/* %-----------------------------------------------------------%
| Call LAPACK routine _steqr to compute the eigenvalues and |
| eigenvectors of the final symmetric tridiagonal matrix H. |
| Initialize the eigenvector matrix Q to the identity. |
%-----------------------------------------------------------% */
i__1 = *ncv - 1;
igraphdcopy_(&i__1, &workl[ih + 1], &c__1, &workl[ihb], &c__1);
igraphdcopy_(ncv, &workl[ih + ldh], &c__1, &workl[ihd], &c__1);
igraphdsteqr_("Identity", ncv, &workl[ihd], &workl[ihb], &workl[iq], &ldq, &
workl[iw], &ierr);
if (ierr != 0) {
*info = -8;
goto L9000;
}
if (msglvl > 1) {
igraphdcopy_(ncv, &workl[iq + *ncv - 1], &ldq, &workl[iw], &c__1);
igraphdvout_(&logfil, ncv, &workl[ihd], &ndigit, "_seupd: NCV Ritz val"
"ues of the final H matrix", (ftnlen)45);
igraphdvout_(&logfil, ncv, &workl[iw], &ndigit, "_seupd: last row of t"
"he eigenvector matrix for H", (ftnlen)48);
}
if (reord) {
/* %---------------------------------------------%
| Reordered the eigenvalues and eigenvectors |
| computed by _steqr so that the "converged" |
| eigenvalues appear in the first NCONV |
| positions of workl(ihd), and the associated |
| eigenvectors appear in the first NCONV |
| columns. |
%---------------------------------------------% */
leftptr = 1;
rghtptr = *ncv;
if (*ncv == 1) {
goto L30;
}
L20:
if (select[leftptr]) {
/* %-------------------------------------------%
| Search, from the left, for the first Ritz |
| value that has not converged. |
%-------------------------------------------% */
++leftptr;
} else if (! select[rghtptr]) {
/* %----------------------------------------------%
| Search, from the right, the first Ritz value |
| that has converged. |
%----------------------------------------------% */
--rghtptr;
} else {
/* %----------------------------------------------%
| Swap the Ritz value on the left that has not |
| converged with the Ritz value on the right |
| that has converged. Swap the associated |
| eigenvector of the tridiagonal matrix H as |
| well. |
%----------------------------------------------% */
temp = workl[ihd + leftptr - 1];
workl[ihd + leftptr - 1] = workl[ihd + rghtptr - 1];
workl[ihd + rghtptr - 1] = temp;
igraphdcopy_(ncv, &workl[iq + *ncv * (leftptr - 1)], &c__1, &workl[
iw], &c__1);
igraphdcopy_(ncv, &workl[iq + *ncv * (rghtptr - 1)], &c__1, &workl[
iq + *ncv * (leftptr - 1)], &c__1);
igraphdcopy_(ncv, &workl[iw], &c__1, &workl[iq + *ncv * (rghtptr -
1)], &c__1);
++leftptr;
--rghtptr;
}
if (leftptr < rghtptr) {
goto L20;
}
L30:
;
}
if (msglvl > 2) {
igraphdvout_(&logfil, ncv, &workl[ihd], &ndigit, "_seupd: The eigenval"
"ues of H--reordered", (ftnlen)39);
}
/* %----------------------------------------%
| Load the converged Ritz values into D. |
%----------------------------------------% */
igraphdcopy_(&nconv, &workl[ihd], &c__1, &d__[1], &c__1);
} else {
/* %-----------------------------------------------------%
| Ritz vectors not required. Load Ritz values into D. |
%-----------------------------------------------------% */
igraphdcopy_(&nconv, &workl[ritz], &c__1, &d__[1], &c__1);
igraphdcopy_(ncv, &workl[ritz], &c__1, &workl[ihd], &c__1);
}
/* %------------------------------------------------------------------%
| Transform the Ritz values and possibly vectors and corresponding |
| Ritz estimates of OP to those of A*x=lambda*B*x. The Ritz values |
| (and corresponding data) are returned in ascending order. |
%------------------------------------------------------------------% */
if (s_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) == 0) {
/* %---------------------------------------------------------%
| Ascending sort of wanted Ritz values, vectors and error |
| bounds. Not necessary if only Ritz values are desired. |
%---------------------------------------------------------% */
if (*rvec) {
igraphdsesrt_("LA", rvec, &nconv, &d__[1], ncv, &workl[iq], &ldq);
} else {
igraphdcopy_(ncv, &workl[bounds], &c__1, &workl[ihb], &c__1);
}
} else {
/* %-------------------------------------------------------------%
| * Make a copy of all the Ritz values. |
| * Transform the Ritz values back to the original system. |
| For TYPE = 'SHIFTI' the transformation is |
| lambda = 1/theta + sigma |
| For TYPE = 'BUCKLE' the transformation is |
| lambda = sigma * theta / ( theta - 1 ) |
| For TYPE = 'CAYLEY' the transformation is |
| lambda = sigma * (theta + 1) / (theta - 1 ) |
| where the theta are the Ritz values returned by dsaupd. |
| NOTES: |
| *The Ritz vectors are not affected by the transformation. |
| They are only reordered. |
%-------------------------------------------------------------% */
igraphdcopy_(ncv, &workl[ihd], &c__1, &workl[iw], &c__1);
if (s_cmp(type__, "SHIFTI", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
workl[ihd + k - 1] = 1. / workl[ihd + k - 1] + *sigma;
/* L40: */
}
} else if (s_cmp(type__, "BUCKLE", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
workl[ihd + k - 1] = *sigma * workl[ihd + k - 1] / (workl[ihd
+ k - 1] - 1.);
/* L50: */
}
} else if (s_cmp(type__, "CAYLEY", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
workl[ihd + k - 1] = *sigma * (workl[ihd + k - 1] + 1.) / (
workl[ihd + k - 1] - 1.);
/* L60: */
}
}
/* %-------------------------------------------------------------%
| * Store the wanted NCONV lambda values into D. |
| * Sort the NCONV wanted lambda in WORKL(IHD:IHD+NCONV-1) |
| into ascending order and apply sort to the NCONV theta |
| values in the transformed system. We'll need this to |
| compute Ritz estimates in the original system. |
| * Finally sort the lambda's into ascending order and apply |
| to Ritz vectors if wanted. Else just sort lambda's into |
| ascending order. |
| NOTES: |
| *workl(iw:iw+ncv-1) contain the theta ordered so that they |
| match the ordering of the lambda. We'll use them again for |
| Ritz vector purification. |
%-------------------------------------------------------------% */
igraphdcopy_(&nconv, &workl[ihd], &c__1, &d__[1], &c__1);
igraphdsortr_("LA", &c_true, &nconv, &workl[ihd], &workl[iw]);
if (*rvec) {
igraphdsesrt_("LA", rvec, &nconv, &d__[1], ncv, &workl[iq], &ldq);
} else {
igraphdcopy_(ncv, &workl[bounds], &c__1, &workl[ihb], &c__1);
d__1 = bnorm2 / rnorm;
igraphdscal_(ncv, &d__1, &workl[ihb], &c__1);
igraphdsortr_("LA", &c_true, &nconv, &d__[1], &workl[ihb]);
}
}
/* %------------------------------------------------%
| Compute the Ritz vectors. Transform the wanted |
| eigenvectors of the symmetric tridiagonal H by |
| the Lanczos basis matrix V. |
%------------------------------------------------% */
if (*rvec && *(unsigned char *)howmny == 'A') {
/* %----------------------------------------------------------%
| Compute the QR factorization of the matrix representing |
| the wanted invariant subspace located in the first NCONV |
| columns of workl(iq,ldq). |
%----------------------------------------------------------% */
igraphdgeqr2_(ncv, &nconv, &workl[iq], &ldq, &workl[iw + *ncv], &workl[ihb],
&ierr);
/* %--------------------------------------------------------%
| * Postmultiply V by Q. |
| * Copy the first NCONV columns of VQ into Z. |
| The N by NCONV matrix Z is now a matrix representation |
| of the approximate invariant subspace associated with |
| the Ritz values in workl(ihd). |
%--------------------------------------------------------% */
igraphdorm2r_("Right", "Notranspose", n, ncv, &nconv, &workl[iq], &ldq, &
workl[iw + *ncv], &v[v_offset], ldv, &workd[*n + 1], &ierr);
igraphdlacpy_("All", n, &nconv, &v[v_offset], ldv, &z__[z_offset], ldz);
/* %-----------------------------------------------------%
| In order to compute the Ritz estimates for the Ritz |
| values in both systems, need the last row of the |
| eigenvector matrix. Remember, it's in factored form |
%-----------------------------------------------------% */
i__1 = *ncv - 1;
for (j = 1; j <= i__1; ++j) {
workl[ihb + j - 1] = 0.;
/* L65: */
}
workl[ihb + *ncv - 1] = 1.;
igraphdorm2r_("Left", "Transpose", ncv, &c__1, &nconv, &workl[iq], &ldq, &
workl[iw + *ncv], &workl[ihb], ncv, &temp, &ierr);
} else if (*rvec && *(unsigned char *)howmny == 'S') {
/* Not yet implemented. See remark 2 above. */
}
if (s_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) == 0 && *rvec) {
i__1 = *ncv;
for (j = 1; j <= i__1; ++j) {
workl[ihb + j - 1] = rnorm * (d__1 = workl[ihb + j - 1], abs(d__1)
);
/* L70: */
}
} else if (s_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) != 0 && *rvec) {
/* %-------------------------------------------------%
| * Determine Ritz estimates of the theta. |
| If RVEC = .true. then compute Ritz estimates |
| of the theta. |
| If RVEC = .false. then copy Ritz estimates |
| as computed by dsaupd. |
| * Determine Ritz estimates of the lambda. |
%-------------------------------------------------% */
igraphdscal_(ncv, &bnorm2, &workl[ihb], &c__1);
if (s_cmp(type__, "SHIFTI", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
/* Computing 2nd power */
d__2 = workl[iw + k - 1];
workl[ihb + k - 1] = (d__1 = workl[ihb + k - 1], abs(d__1)) /
(d__2 * d__2);
/* L80: */
}
} else if (s_cmp(type__, "BUCKLE", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
/* Computing 2nd power */
d__2 = workl[iw + k - 1] - 1.;
workl[ihb + k - 1] = *sigma * (d__1 = workl[ihb + k - 1], abs(
d__1)) / (d__2 * d__2);
/* L90: */
}
} else if (s_cmp(type__, "CAYLEY", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = *ncv;
for (k = 1; k <= i__1; ++k) {
workl[ihb + k - 1] = (d__1 = workl[ihb + k - 1] / workl[iw +
k - 1] * (workl[iw + k - 1] - 1.), abs(d__1));
/* L100: */
}
}
}
if (s_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) != 0 && msglvl > 1) {
igraphdvout_(&logfil, &nconv, &d__[1], &ndigit, "_seupd: Untransformed con"
"verged Ritz values", (ftnlen)43);
igraphdvout_(&logfil, &nconv, &workl[ihb], &ndigit, "_seupd: Ritz estimate"
"s of the untransformed Ritz values", (ftnlen)55);
} else if (msglvl > 1) {
igraphdvout_(&logfil, &nconv, &d__[1], &ndigit, "_seupd: Converged Ritz va"
"lues", (ftnlen)29);
igraphdvout_(&logfil, &nconv, &workl[ihb], &ndigit, "_seupd: Associated Ri"
"tz estimates", (ftnlen)33);
}
/* %-------------------------------------------------%
| Ritz vector purification step. Formally perform |
| one of inverse subspace iteration. Only used |
| for MODE = 3,4,5. See reference 7 |
%-------------------------------------------------% */
if (*rvec && (s_cmp(type__, "SHIFTI", (ftnlen)6, (ftnlen)6) == 0 || s_cmp(
type__, "CAYLEY", (ftnlen)6, (ftnlen)6) == 0)) {
i__1 = nconv - 1;
for (k = 0; k <= i__1; ++k) {
workl[iw + k] = workl[iq + k * ldq + *ncv - 1] / workl[iw + k];
/* L110: */
}
} else if (*rvec && s_cmp(type__, "BUCKLE", (ftnlen)6, (ftnlen)6) == 0) {
i__1 = nconv - 1;
for (k = 0; k <= i__1; ++k) {
workl[iw + k] = workl[iq + k * ldq + *ncv - 1] / (workl[iw + k] -
1.);
/* L120: */
}
}
if (s_cmp(type__, "REGULR", (ftnlen)6, (ftnlen)6) != 0) {
igraphdger_(n, &nconv, &c_b119, &resid[1], &c__1, &workl[iw], &c__1, &z__[
z_offset], ldz);
}
L9000:
return 0;
/* %---------------%
| End of dseupd |
%---------------% */
} /* igraphdseupd_ */
