int zhbev_(char *jobz, char *uplo, int *n, int *kd,
doublecomplex *ab, int *ldab, double *w, doublecomplex *z__,
int *ldz, doublecomplex *work, double *rwork, int *info)
{
/* System generated locals */
int ab_dim1, ab_offset, z_dim1, z_offset, i__1;
double d__1;
/* Builtin functions */
double sqrt(double);
/* Local variables */
double eps;
int inde;
double anrm;
int imax;
double rmin, rmax;
extern int dscal_(int *, double *, double *,
int *);
double sigma;
extern int lsame_(char *, char *);
int iinfo;
int lower, wantz;
extern double dlamch_(char *);
int iscale;
double safmin;
extern double zlanhb_(char *, char *, int *, int *,
doublecomplex *, int *, double *);
extern int xerbla_(char *, int *);
double bignum;
extern int dsterf_(int *, double *, double *,
int *), zlascl_(char *, int *, int *, double *,
double *, int *, int *, doublecomplex *, int *,
int *), zhbtrd_(char *, char *, int *, int *,
doublecomplex *, int *, double *, double *,
doublecomplex *, int *, doublecomplex *, int *);
int indrwk;
double smlnum;
extern int zsteqr_(char *, int *, double *,
double *, doublecomplex *, int *, double *, int *);
/* -- LAPACK driver routine (version 3.2) -- */
/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/* November 2006 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ZHBEV computes all the eigenvalues and, optionally, eigenvectors of */
/* a complex Hermitian band matrix A. */
/* Arguments */
/* ========= */
/* JOBZ (input) CHARACTER*1 */
/* = 'N': Compute eigenvalues only; */
/* = 'V': Compute eigenvalues and eigenvectors. */
/* UPLO (input) CHARACTER*1 */
/* = 'U': Upper triangle of A is stored; */
/* = 'L': Lower triangle of A is stored. */
/* N (input) INTEGER */
/* The order of the matrix A. N >= 0. */
/* KD (input) INTEGER */
/* The number of superdiagonals of the matrix A if UPLO = 'U', */
/* or the number of subdiagonals if UPLO = 'L'. KD >= 0. */
/* AB (input/output) COMPLEX*16 array, dimension (LDAB, N) */
/* On entry, the upper or lower triangle of the Hermitian band */
/* matrix A, stored in the first KD+1 rows of the array. The */
/* j-th column of A is stored in the j-th column of the array AB */
/* as follows: */
/* if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for MAX(1,j-kd)<=i<=j; */
/* if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j<=i<=MIN(n,j+kd). */
/* On exit, AB is overwritten by values generated during the */
/* reduction to tridiagonal form. If UPLO = 'U', the first */
/* superdiagonal and the diagonal of the tridiagonal matrix T */
/* are returned in rows KD and KD+1 of AB, and if UPLO = 'L', */
/* the diagonal and first subdiagonal of T are returned in the */
/* first two rows of AB. */
/* LDAB (input) INTEGER */
/* The leading dimension of the array AB. LDAB >= KD + 1. */
/* W (output) DOUBLE PRECISION array, dimension (N) */
/* If INFO = 0, the eigenvalues in ascending order. */
/* Z (output) COMPLEX*16 array, dimension (LDZ, N) */
/* If JOBZ = 'V', then if INFO = 0, Z contains the orthonormal */
/* eigenvectors of the matrix A, with the i-th column of Z */
/* holding the eigenvector associated with W(i). */
/* If JOBZ = 'N', then Z is not referenced. */
/* LDZ (input) INTEGER */
/* The leading dimension of the array Z. LDZ >= 1, and if */
/* JOBZ = 'V', LDZ >= MAX(1,N). */
/* WORK (workspace) COMPLEX*16 array, dimension (N) */
/* RWORK (workspace) DOUBLE PRECISION array, dimension (MAX(1,3*N-2)) */
/* INFO (output) INTEGER */
/* = 0: successful exit. */
/* < 0: if INFO = -i, the i-th argument had an illegal value. */
/* > 0: if INFO = i, the algorithm failed to converge; i */
/* off-diagonal elements of an intermediate tridiagonal */
/* form did not converge to zero. */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Test the input parameters. */
/* Parameter adjustments */
ab_dim1 = *ldab;
ab_offset = 1 + ab_dim1;
ab -= ab_offset;
--w;
z_dim1 = *ldz;
z_offset = 1 + z_dim1;
z__ -= z_offset;
--work;
--rwork;
/* Function Body */
wantz = lsame_(jobz, "V");
lower = lsame_(uplo, "L");
*info = 0;
if (! (wantz || lsame_(jobz, "N"))) {
*info = -1;
} else if (! (lower || lsame_(uplo, "U"))) {
*info = -2;
} else if (*n < 0) {
*info = -3;
} else if (*kd < 0) {
*info = -4;
} else if (*ldab < *kd + 1) {
*info = -6;
} else if (*ldz < 1 || wantz && *ldz < *n) {
*info = -9;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZHBEV ", &i__1);
return 0;
}
/* Quick return if possible */
if (*n == 0) {
return 0;
}
if (*n == 1) {
if (lower) {
i__1 = ab_dim1 + 1;
w[1] = ab[i__1].r;
} else {
i__1 = *kd + 1 + ab_dim1;
w[1] = ab[i__1].r;
}
if (wantz) {
i__1 = z_dim1 + 1;
z__[i__1].r = 1., z__[i__1].i = 0.;
}
return 0;
}
/* Get machine constants. */
safmin = dlamch_("Safe minimum");
eps = dlamch_("Precision");
smlnum = safmin / eps;
bignum = 1. / smlnum;
rmin = sqrt(smlnum);
rmax = sqrt(bignum);
/* Scale matrix to allowable range, if necessary. */
anrm = zlanhb_("M", uplo, n, kd, &ab[ab_offset], ldab, &rwork[1]);
iscale = 0;
if (anrm > 0. && anrm < rmin) {
iscale = 1;
sigma = rmin / anrm;
} else if (anrm > rmax) {
iscale = 1;
sigma = rmax / anrm;
}
if (iscale == 1) {
if (lower) {
zlascl_("B", kd, kd, &c_b11, &sigma, n, n, &ab[ab_offset], ldab,
info);
} else {
zlascl_("Q", kd, kd, &c_b11, &sigma, n, n, &ab[ab_offset], ldab,
info);
}
}
/* Call ZHBTRD to reduce Hermitian band matrix to tridiagonal form. */
inde = 1;
zhbtrd_(jobz, uplo, n, kd, &ab[ab_offset], ldab, &w[1], &rwork[inde], &
z__[z_offset], ldz, &work[1], &iinfo);
/* For eigenvalues only, call DSTERF. For eigenvectors, call ZSTEQR. */
if (! wantz) {
dsterf_(n, &w[1], &rwork[inde], info);
} else {
indrwk = inde + *n;
zsteqr_(jobz, n, &w[1], &rwork[inde], &z__[z_offset], ldz, &rwork[
indrwk], info);
}
/* If matrix was scaled, then rescale eigenvalues appropriately. */
if (iscale == 1) {
if (*info == 0) {
imax = *n;
} else {
imax = *info - 1;
}
d__1 = 1. / sigma;
dscal_(&imax, &d__1, &w[1], &c__1);
}
return 0;
/* End of ZHBEV */
} /* zhbev_ */
/* Subroutine */
int zpbsvx_(char *fact, char *uplo, integer *n, integer *kd, integer *nrhs, doublecomplex *ab, integer *ldab, doublecomplex *afb, integer *ldafb, char *equed, doublereal *s, doublecomplex *b, integer *ldb, doublecomplex *x, integer *ldx, doublereal *rcond, doublereal * ferr, doublereal *berr, doublecomplex *work, doublereal *rwork, integer *info)
{
/* System generated locals */
integer ab_dim1, ab_offset, afb_dim1, afb_offset, b_dim1, b_offset, x_dim1, x_offset, i__1, i__2, i__3, i__4, i__5;
doublereal d__1, d__2;
doublecomplex z__1;
/* Local variables */
integer i__, j, j1, j2;
doublereal amax, smin, smax;
extern logical lsame_(char *, char *);
doublereal scond, anorm;
logical equil, rcequ, upper;
extern /* Subroutine */
int zcopy_(integer *, doublecomplex *, integer *, doublecomplex *, integer *);
extern doublereal dlamch_(char *);
logical nofact;
extern /* Subroutine */
int xerbla_(char *, integer *);
extern doublereal zlanhb_(char *, char *, integer *, integer *, doublecomplex *, integer *, doublereal *);
doublereal bignum;
extern /* Subroutine */
int zlaqhb_(char *, integer *, integer *, doublecomplex *, integer *, doublereal *, doublereal *, doublereal *, char *);
integer infequ;
extern /* Subroutine */
int zpbcon_(char *, integer *, integer *, doublecomplex *, integer *, doublereal *, doublereal *, doublecomplex *, doublereal *, integer *), zlacpy_(char *, integer *, integer *, doublecomplex *, integer *, doublecomplex * , integer *), zpbequ_(char *, integer *, integer *, doublecomplex *, integer *, doublereal *, doublereal *, doublereal *, integer *), zpbrfs_(char *, integer *, integer *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, doublecomplex *, integer * , doublereal *, doublereal *, doublecomplex *, doublereal *, integer *), zpbtrf_(char *, integer *, integer *, doublecomplex *, integer *, integer *);
doublereal smlnum;
extern /* Subroutine */
int zpbtrs_(char *, integer *, integer *, integer *, doublecomplex *, integer *, doublecomplex *, integer *, integer *);
/* -- LAPACK driver routine (version 3.4.1) -- */
/* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
/* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
/* April 2012 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Parameter adjustments */
ab_dim1 = *ldab;
ab_offset = 1 + ab_dim1;
ab -= ab_offset;
afb_dim1 = *ldafb;
afb_offset = 1 + afb_dim1;
afb -= afb_offset;
--s;
b_dim1 = *ldb;
b_offset = 1 + b_dim1;
b -= b_offset;
x_dim1 = *ldx;
x_offset = 1 + x_dim1;
x -= x_offset;
--ferr;
--berr;
--work;
--rwork;
/* Function Body */
*info = 0;
nofact = lsame_(fact, "N");
equil = lsame_(fact, "E");
upper = lsame_(uplo, "U");
if (nofact || equil)
{
*(unsigned char *)equed = 'N';
rcequ = FALSE_;
}
else
{
rcequ = lsame_(equed, "Y");
smlnum = dlamch_("Safe minimum");
bignum = 1. / smlnum;
}
/* Test the input parameters. */
if (! nofact && ! equil && ! lsame_(fact, "F"))
{
*info = -1;
}
else if (! upper && ! lsame_(uplo, "L"))
{
*info = -2;
}
else if (*n < 0)
{
*info = -3;
}
else if (*kd < 0)
{
*info = -4;
}
else if (*nrhs < 0)
{
*info = -5;
}
else if (*ldab < *kd + 1)
{
*info = -7;
}
else if (*ldafb < *kd + 1)
{
*info = -9;
}
else if (lsame_(fact, "F") && ! (rcequ || lsame_( equed, "N")))
{
*info = -10;
}
else
{
if (rcequ)
{
smin = bignum;
smax = 0.;
i__1 = *n;
for (j = 1;
j <= i__1;
++j)
{
/* Computing MIN */
d__1 = smin;
d__2 = s[j]; // , expr subst
smin = min(d__1,d__2);
/* Computing MAX */
d__1 = smax;
d__2 = s[j]; // , expr subst
smax = max(d__1,d__2);
/* L10: */
}
if (smin <= 0.)
{
*info = -11;
}
else if (*n > 0)
{
scond = max(smin,smlnum) / min(smax,bignum);
}
else
{
scond = 1.;
}
}
if (*info == 0)
{
if (*ldb < max(1,*n))
{
*info = -13;
}
else if (*ldx < max(1,*n))
{
*info = -15;
}
}
}
if (*info != 0)
{
i__1 = -(*info);
xerbla_("ZPBSVX", &i__1);
return 0;
}
if (equil)
{
/* Compute row and column scalings to equilibrate the matrix A. */
zpbequ_(uplo, n, kd, &ab[ab_offset], ldab, &s[1], &scond, &amax, & infequ);
if (infequ == 0)
{
/* Equilibrate the matrix. */
zlaqhb_(uplo, n, kd, &ab[ab_offset], ldab, &s[1], &scond, &amax, equed);
rcequ = lsame_(equed, "Y");
}
}
/* Scale the right-hand side. */
if (rcequ)
{
i__1 = *nrhs;
for (j = 1;
j <= i__1;
++j)
{
i__2 = *n;
for (i__ = 1;
i__ <= i__2;
++i__)
{
i__3 = i__ + j * b_dim1;
i__4 = i__;
i__5 = i__ + j * b_dim1;
z__1.r = s[i__4] * b[i__5].r;
z__1.i = s[i__4] * b[i__5].i; // , expr subst
b[i__3].r = z__1.r;
b[i__3].i = z__1.i; // , expr subst
/* L20: */
}
/* L30: */
}
}
if (nofact || equil)
{
/* Compute the Cholesky factorization A = U**H *U or A = L*L**H. */
if (upper)
{
i__1 = *n;
for (j = 1;
j <= i__1;
++j)
{
/* Computing MAX */
i__2 = j - *kd;
j1 = max(i__2,1);
i__2 = j - j1 + 1;
zcopy_(&i__2, &ab[*kd + 1 - j + j1 + j * ab_dim1], &c__1, & afb[*kd + 1 - j + j1 + j * afb_dim1], &c__1);
/* L40: */
}
}
else
{
i__1 = *n;
for (j = 1;
j <= i__1;
++j)
{
/* Computing MIN */
i__2 = j + *kd;
j2 = min(i__2,*n);
i__2 = j2 - j + 1;
zcopy_(&i__2, &ab[j * ab_dim1 + 1], &c__1, &afb[j * afb_dim1 + 1], &c__1);
/* L50: */
}
}
zpbtrf_(uplo, n, kd, &afb[afb_offset], ldafb, info);
/* Return if INFO is non-zero. */
if (*info > 0)
{
*rcond = 0.;
return 0;
}
}
/* Compute the norm of the matrix A. */
anorm = zlanhb_("1", uplo, n, kd, &ab[ab_offset], ldab, &rwork[1]);
/* Compute the reciprocal of the condition number of A. */
zpbcon_(uplo, n, kd, &afb[afb_offset], ldafb, &anorm, rcond, &work[1], & rwork[1], info);
/* Compute the solution matrix X. */
zlacpy_("Full", n, nrhs, &b[b_offset], ldb, &x[x_offset], ldx);
zpbtrs_(uplo, n, kd, nrhs, &afb[afb_offset], ldafb, &x[x_offset], ldx, info);
/* Use iterative refinement to improve the computed solution and */
/* compute error bounds and backward error estimates for it. */
zpbrfs_(uplo, n, kd, nrhs, &ab[ab_offset], ldab, &afb[afb_offset], ldafb, &b[b_offset], ldb, &x[x_offset], ldx, &ferr[1], &berr[1], &work[1] , &rwork[1], info);
/* Transform the solution matrix X to a solution of the original */
/* system. */
if (rcequ)
{
i__1 = *nrhs;
for (j = 1;
j <= i__1;
++j)
{
i__2 = *n;
for (i__ = 1;
i__ <= i__2;
++i__)
{
i__3 = i__ + j * x_dim1;
i__4 = i__;
i__5 = i__ + j * x_dim1;
z__1.r = s[i__4] * x[i__5].r;
z__1.i = s[i__4] * x[i__5].i; // , expr subst
x[i__3].r = z__1.r;
x[i__3].i = z__1.i; // , expr subst
/* L60: */
}
/* L70: */
}
i__1 = *nrhs;
for (j = 1;
j <= i__1;
++j)
{
ferr[j] /= scond;
/* L80: */
}
}
/* Set INFO = N+1 if the matrix is singular to working precision. */
if (*rcond < dlamch_("Epsilon"))
{
*info = *n + 1;
}
return 0;
/* End of ZPBSVX */
}
/* Subroutine */ int zdrvpb_(logical *dotype, integer *nn, integer *nval,
integer *nrhs, doublereal *thresh, logical *tsterr, integer *nmax,
doublecomplex *a, doublecomplex *afac, doublecomplex *asav,
doublecomplex *b, doublecomplex *bsav, doublecomplex *x,
doublecomplex *xact, doublereal *s, doublecomplex *work, doublereal *
rwork, integer *nout)
{
/* Initialized data */
static integer iseedy[4] = { 1988,1989,1990,1991 };
static char facts[1*3] = "F" "N" "E";
static char equeds[1*2] = "N" "Y";
/* Format strings */
static char fmt_9999[] = "(1x,a6,\002, UPLO='\002,a1,\002', N =\002,i5"
",\002, KD =\002,i5,\002, type \002,i1,\002, test(\002,i1,\002)"
"=\002,g12.5)";
static char fmt_9997[] = "(1x,a6,\002( '\002,a1,\002', '\002,a1,\002',"
" \002,i5,\002, \002,i5,\002, ... ), EQUED='\002,a1,\002', type"
" \002,i1,\002, test(\002,i1,\002)=\002,g12.5)";
static char fmt_9998[] = "(1x,a6,\002( '\002,a1,\002', '\002,a1,\002',"
" \002,i5,\002, \002,i5,\002, ... ), type \002,i1,\002, test(\002"
",i1,\002)=\002,g12.5)";
/* System generated locals */
address a__1[2];
integer i__1, i__2, i__3, i__4, i__5, i__6, i__7[2];
char ch__1[2];
/* Builtin functions
Subroutine */ int s_copy(char *, char *, ftnlen, ftnlen);
integer s_wsfe(cilist *), do_fio(integer *, char *, ftnlen), e_wsfe(void);
/* Subroutine */ int s_cat(char *, char **, integer *, integer *, ftnlen);
/* Local variables */
static integer ldab;
static char fact[1];
static integer ioff, mode, koff;
static doublereal amax;
static char path[3];
static integer imat, info;
static char dist[1], uplo[1], type__[1];
static integer nrun, i__, k, n, ifact, nfail, iseed[4], nfact;
extern doublereal dget06_(doublereal *, doublereal *);
static integer kdval[4];
extern logical lsame_(char *, char *);
static char equed[1];
static integer nbmin;
static doublereal rcond, roldc, scond;
static integer nimat;
static doublereal anorm;
extern /* Subroutine */ int zget04_(integer *, integer *, doublecomplex *,
integer *, doublecomplex *, integer *, doublereal *, doublereal *
);
static logical equil;
extern /* Subroutine */ int zpbt01_(char *, integer *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublereal *, doublereal *), zpbt02_(char *, integer *,
integer *, integer *, doublecomplex *, integer *, doublecomplex *,
integer *, doublecomplex *, integer *, doublereal *, doublereal *
), zpbt05_(char *, integer *, integer *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublereal *, doublereal *, doublereal *);
static integer iuplo, izero, i1, i2, k1, nerrs;
static logical zerot;
extern /* Subroutine */ int zcopy_(integer *, doublecomplex *, integer *,
doublecomplex *, integer *), zpbsv_(char *, integer *, integer *,
integer *, doublecomplex *, integer *, doublecomplex *, integer *,
integer *), zswap_(integer *, doublecomplex *, integer *,
doublecomplex *, integer *);
static char xtype[1];
extern /* Subroutine */ int zlatb4_(char *, integer *, integer *, integer
*, char *, integer *, integer *, doublereal *, integer *,
doublereal *, char *), aladhd_(integer *,
char *);
static integer kd, nb, in, kl;
extern /* Subroutine */ int alaerh_(char *, char *, integer *, integer *,
char *, integer *, integer *, integer *, integer *, integer *,
integer *, integer *, integer *, integer *);
static logical prefac;
static integer iw, ku, nt;
static doublereal rcondc;
static logical nofact;
static char packit[1];
static integer iequed;
extern doublereal zlanhb_(char *, char *, integer *, integer *,
doublecomplex *, integer *, doublereal *),
zlange_(char *, integer *, integer *, doublecomplex *, integer *,
doublereal *);
extern /* Subroutine */ int zlaqhb_(char *, integer *, integer *,
doublecomplex *, integer *, doublereal *, doublereal *,
doublereal *, char *), alasvm_(char *, integer *,
integer *, integer *, integer *);
static doublereal cndnum;
extern /* Subroutine */ int zlaipd_(integer *, doublecomplex *, integer *,
integer *);
static doublereal ainvnm;
extern /* Subroutine */ int xlaenv_(integer *, integer *), zlacpy_(char *,
integer *, integer *, doublecomplex *, integer *, doublecomplex *
, integer *), zlarhs_(char *, char *, char *, char *,
integer *, integer *, integer *, integer *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *, integer *, integer *), zlaset_(char *, integer *, integer *,
doublecomplex *, doublecomplex *, doublecomplex *, integer *), zpbequ_(char *, integer *, integer *, doublecomplex *,
integer *, doublereal *, doublereal *, doublereal *, integer *), zpbtrf_(char *, integer *, integer *, doublecomplex *,
integer *, integer *), zlatms_(integer *, integer *, char
*, integer *, char *, doublereal *, integer *, doublereal *,
doublereal *, integer *, integer *, char *, doublecomplex *,
integer *, doublecomplex *, integer *);
static doublereal result[6];
extern /* Subroutine */ int zpbtrs_(char *, integer *, integer *, integer
*, doublecomplex *, integer *, doublecomplex *, integer *,
integer *), zpbsvx_(char *, char *, integer *, integer *,
integer *, doublecomplex *, integer *, doublecomplex *, integer *,
char *, doublereal *, doublecomplex *, integer *, doublecomplex *
, integer *, doublereal *, doublereal *, doublereal *,
doublecomplex *, doublereal *, integer *),
zerrvx_(char *, integer *);
static integer lda, ikd, nkd;
/* Fortran I/O blocks */
static cilist io___57 = { 0, 0, 0, fmt_9999, 0 };
static cilist io___60 = { 0, 0, 0, fmt_9997, 0 };
static cilist io___61 = { 0, 0, 0, fmt_9998, 0 };
/* -- LAPACK test routine (version 3.0) --
Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
Courant Institute, Argonne National Lab, and Rice University
June 30, 1999
Purpose
=======
ZDRVPB tests the driver routines ZPBSV and -SVX.
Arguments
=========
DOTYPE (input) LOGICAL array, dimension (NTYPES)
The matrix types to be used for testing. Matrices of type j
(for 1 <= j <= NTYPES) are used for testing if DOTYPE(j) =
.TRUE.; if DOTYPE(j) = .FALSE., then type j is not used.
NN (input) INTEGER
The number of values of N contained in the vector NVAL.
NVAL (input) INTEGER array, dimension (NN)
The values of the matrix dimension N.
NRHS (input) INTEGER
The number of right hand side vectors to be generated for
each linear system.
THRESH (input) DOUBLE PRECISION
The threshold value for the test ratios. A result is
included in the output file if RESULT >= THRESH. To have
every test ratio printed, use THRESH = 0.
TSTERR (input) LOGICAL
Flag that indicates whether error exits are to be tested.
NMAX (input) INTEGER
The maximum value permitted for N, used in dimensioning the
work arrays.
A (workspace) COMPLEX*16 array, dimension (NMAX*NMAX)
AFAC (workspace) COMPLEX*16 array, dimension (NMAX*NMAX)
ASAV (workspace) COMPLEX*16 array, dimension (NMAX*NMAX)
B (workspace) COMPLEX*16 array, dimension (NMAX*NRHS)
BSAV (workspace) COMPLEX*16 array, dimension (NMAX*NRHS)
X (workspace) COMPLEX*16 array, dimension (NMAX*NRHS)
XACT (workspace) COMPLEX*16 array, dimension (NMAX*NRHS)
S (workspace) DOUBLE PRECISION array, dimension (NMAX)
WORK (workspace) COMPLEX*16 array, dimension
(NMAX*max(3,NRHS))
RWORK (workspace) DOUBLE PRECISION array, dimension (NMAX+2*NRHS)
NOUT (input) INTEGER
The unit number for output.
=====================================================================
Parameter adjustments */
--rwork;
--work;
--s;
--xact;
--x;
--bsav;
--b;
--asav;
--afac;
--a;
--nval;
--dotype;
/* Function Body
Initialize constants and the random number seed. */
s_copy(path, "Zomplex precision", (ftnlen)1, (ftnlen)17);
s_copy(path + 1, "PB", (ftnlen)2, (ftnlen)2);
nrun = 0;
nfail = 0;
nerrs = 0;
for (i__ = 1; i__ <= 4; ++i__) {
iseed[i__ - 1] = iseedy[i__ - 1];
/* L10: */
}
/* Test the error exits */
if (*tsterr) {
zerrvx_(path, nout);
}
infoc_1.infot = 0;
kdval[0] = 0;
/* Set the block size and minimum block size for testing. */
nb = 1;
nbmin = 2;
xlaenv_(&c__1, &nb);
xlaenv_(&c__2, &nbmin);
/* Do for each value of N in NVAL */
i__1 = *nn;
for (in = 1; in <= i__1; ++in) {
n = nval[in];
lda = max(n,1);
*(unsigned char *)xtype = 'N';
/* Set limits on the number of loop iterations.
Computing MAX */
i__2 = 1, i__3 = min(n,4);
nkd = max(i__2,i__3);
nimat = 8;
if (n == 0) {
nimat = 1;
}
kdval[1] = n + (n + 1) / 4;
kdval[2] = (n * 3 - 1) / 4;
kdval[3] = (n + 1) / 4;
i__2 = nkd;
for (ikd = 1; ikd <= i__2; ++ikd) {
/* Do for KD = 0, (5*N+1)/4, (3N-1)/4, and (N+1)/4. This order
makes it easier to skip redundant values for small values
of N. */
kd = kdval[ikd - 1];
ldab = kd + 1;
/* Do first for UPLO = 'U', then for UPLO = 'L' */
for (iuplo = 1; iuplo <= 2; ++iuplo) {
koff = 1;
if (iuplo == 1) {
*(unsigned char *)uplo = 'U';
*(unsigned char *)packit = 'Q';
/* Computing MAX */
i__3 = 1, i__4 = kd + 2 - n;
koff = max(i__3,i__4);
} else {
*(unsigned char *)uplo = 'L';
*(unsigned char *)packit = 'B';
}
i__3 = nimat;
for (imat = 1; imat <= i__3; ++imat) {
/* Do the tests only if DOTYPE( IMAT ) is true. */
if (! dotype[imat]) {
goto L80;
}
/* Skip types 2, 3, or 4 if the matrix size is too small. */
zerot = imat >= 2 && imat <= 4;
if (zerot && n < imat - 1) {
goto L80;
}
if (! zerot || ! dotype[1]) {
/* Set up parameters with ZLATB4 and generate a test
matrix with ZLATMS. */
zlatb4_(path, &imat, &n, &n, type__, &kl, &ku, &anorm,
&mode, &cndnum, dist);
s_copy(srnamc_1.srnamt, "ZLATMS", (ftnlen)6, (ftnlen)
6);
zlatms_(&n, &n, dist, iseed, type__, &rwork[1], &mode,
&cndnum, &anorm, &kd, &kd, packit, &a[koff],
&ldab, &work[1], &info);
/* Check error code from ZLATMS. */
if (info != 0) {
alaerh_(path, "ZLATMS", &info, &c__0, uplo, &n, &
n, &c_n1, &c_n1, &c_n1, &imat, &nfail, &
nerrs, nout);
goto L80;
}
} else if (izero > 0) {
/* Use the same matrix for types 3 and 4 as for type
2 by copying back the zeroed out column, */
iw = (lda << 1) + 1;
if (iuplo == 1) {
ioff = (izero - 1) * ldab + kd + 1;
i__4 = izero - i1;
zcopy_(&i__4, &work[iw], &c__1, &a[ioff - izero +
i1], &c__1);
iw = iw + izero - i1;
i__4 = i2 - izero + 1;
/* Computing MAX */
i__6 = ldab - 1;
i__5 = max(i__6,1);
zcopy_(&i__4, &work[iw], &c__1, &a[ioff], &i__5);
} else {
ioff = (i1 - 1) * ldab + 1;
i__4 = izero - i1;
/* Computing MAX */
i__6 = ldab - 1;
i__5 = max(i__6,1);
zcopy_(&i__4, &work[iw], &c__1, &a[ioff + izero -
i1], &i__5);
ioff = (izero - 1) * ldab + 1;
iw = iw + izero - i1;
i__4 = i2 - izero + 1;
zcopy_(&i__4, &work[iw], &c__1, &a[ioff], &c__1);
}
}
/* For types 2-4, zero one row and column of the matrix
to test that INFO is returned correctly. */
izero = 0;
if (zerot) {
if (imat == 2) {
izero = 1;
} else if (imat == 3) {
izero = n;
} else {
izero = n / 2 + 1;
}
/* Save the zeroed out row and column in WORK(*,3) */
iw = lda << 1;
/* Computing MIN */
i__5 = (kd << 1) + 1;
i__4 = min(i__5,n);
for (i__ = 1; i__ <= i__4; ++i__) {
i__5 = iw + i__;
work[i__5].r = 0., work[i__5].i = 0.;
/* L20: */
}
++iw;
/* Computing MAX */
i__4 = izero - kd;
i1 = max(i__4,1);
/* Computing MIN */
i__4 = izero + kd;
i2 = min(i__4,n);
if (iuplo == 1) {
ioff = (izero - 1) * ldab + kd + 1;
i__4 = izero - i1;
zswap_(&i__4, &a[ioff - izero + i1], &c__1, &work[
iw], &c__1);
iw = iw + izero - i1;
i__4 = i2 - izero + 1;
/* Computing MAX */
i__6 = ldab - 1;
i__5 = max(i__6,1);
zswap_(&i__4, &a[ioff], &i__5, &work[iw], &c__1);
} else {
ioff = (i1 - 1) * ldab + 1;
i__4 = izero - i1;
/* Computing MAX */
i__6 = ldab - 1;
i__5 = max(i__6,1);
zswap_(&i__4, &a[ioff + izero - i1], &i__5, &work[
iw], &c__1);
ioff = (izero - 1) * ldab + 1;
iw = iw + izero - i1;
i__4 = i2 - izero + 1;
zswap_(&i__4, &a[ioff], &c__1, &work[iw], &c__1);
}
}
/* Set the imaginary part of the diagonals. */
if (iuplo == 1) {
zlaipd_(&n, &a[kd + 1], &ldab, &c__0);
} else {
zlaipd_(&n, &a[1], &ldab, &c__0);
}
/* Save a copy of the matrix A in ASAV. */
i__4 = kd + 1;
zlacpy_("Full", &i__4, &n, &a[1], &ldab, &asav[1], &ldab);
for (iequed = 1; iequed <= 2; ++iequed) {
*(unsigned char *)equed = *(unsigned char *)&equeds[
iequed - 1];
if (iequed == 1) {
nfact = 3;
} else {
nfact = 1;
}
i__4 = nfact;
for (ifact = 1; ifact <= i__4; ++ifact) {
*(unsigned char *)fact = *(unsigned char *)&facts[
ifact - 1];
prefac = lsame_(fact, "F");
nofact = lsame_(fact, "N");
equil = lsame_(fact, "E");
if (zerot) {
if (prefac) {
goto L60;
}
rcondc = 0.;
} else if (! lsame_(fact, "N")) {
/* Compute the condition number for comparison
with the value returned by ZPBSVX (FACT =
'N' reuses the condition number from the
previous iteration with FACT = 'F'). */
i__5 = kd + 1;
zlacpy_("Full", &i__5, &n, &asav[1], &ldab, &
afac[1], &ldab);
if (equil || iequed > 1) {
/* Compute row and column scale factors to
equilibrate the matrix A. */
zpbequ_(uplo, &n, &kd, &afac[1], &ldab, &
s[1], &scond, &amax, &info);
if (info == 0 && n > 0) {
if (iequed > 1) {
scond = 0.;
}
/* Equilibrate the matrix. */
zlaqhb_(uplo, &n, &kd, &afac[1], &
ldab, &s[1], &scond, &amax,
equed);
}
}
/* Save the condition number of the
non-equilibrated system for use in ZGET04. */
if (equil) {
roldc = rcondc;
}
/* Compute the 1-norm of A. */
anorm = zlanhb_("1", uplo, &n, &kd, &afac[1],
&ldab, &rwork[1]);
/* Factor the matrix A. */
zpbtrf_(uplo, &n, &kd, &afac[1], &ldab, &info);
/* Form the inverse of A. */
zlaset_("Full", &n, &n, &c_b47, &c_b48, &a[1],
&lda);
s_copy(srnamc_1.srnamt, "ZPBTRS", (ftnlen)6, (
ftnlen)6);
zpbtrs_(uplo, &n, &kd, &n, &afac[1], &ldab, &
a[1], &lda, &info);
/* Compute the 1-norm condition number of A. */
ainvnm = zlange_("1", &n, &n, &a[1], &lda, &
rwork[1]);
if (anorm <= 0. || ainvnm <= 0.) {
rcondc = 1.;
} else {
rcondc = 1. / anorm / ainvnm;
}
}
/* Restore the matrix A. */
i__5 = kd + 1;
zlacpy_("Full", &i__5, &n, &asav[1], &ldab, &a[1],
&ldab);
/* Form an exact solution and set the right hand
side. */
s_copy(srnamc_1.srnamt, "ZLARHS", (ftnlen)6, (
ftnlen)6);
zlarhs_(path, xtype, uplo, " ", &n, &n, &kd, &kd,
nrhs, &a[1], &ldab, &xact[1], &lda, &b[1],
&lda, iseed, &info);
*(unsigned char *)xtype = 'C';
zlacpy_("Full", &n, nrhs, &b[1], &lda, &bsav[1], &
lda);
if (nofact) {
/* --- Test ZPBSV ---
Compute the L*L' or U'*U factorization of the
matrix and solve the system. */
i__5 = kd + 1;
zlacpy_("Full", &i__5, &n, &a[1], &ldab, &
afac[1], &ldab);
zlacpy_("Full", &n, nrhs, &b[1], &lda, &x[1],
&lda);
s_copy(srnamc_1.srnamt, "ZPBSV ", (ftnlen)6, (
ftnlen)6);
zpbsv_(uplo, &n, &kd, nrhs, &afac[1], &ldab, &
x[1], &lda, &info);
/* Check error code from ZPBSV . */
if (info != izero) {
alaerh_(path, "ZPBSV ", &info, &izero,
uplo, &n, &n, &kd, &kd, nrhs, &
imat, &nfail, &nerrs, nout);
goto L40;
} else if (info != 0) {
goto L40;
}
/* Reconstruct matrix from factors and compute
residual. */
zpbt01_(uplo, &n, &kd, &a[1], &ldab, &afac[1],
&ldab, &rwork[1], result);
/* Compute residual of the computed solution. */
zlacpy_("Full", &n, nrhs, &b[1], &lda, &work[
1], &lda);
zpbt02_(uplo, &n, &kd, nrhs, &a[1], &ldab, &x[
1], &lda, &work[1], &lda, &rwork[1], &
result[1]);
/* Check solution from generated exact solution. */
zget04_(&n, nrhs, &x[1], &lda, &xact[1], &lda,
&rcondc, &result[2]);
nt = 3;
/* Print information about the tests that did
not pass the threshold. */
i__5 = nt;
for (k = 1; k <= i__5; ++k) {
if (result[k - 1] >= *thresh) {
if (nfail == 0 && nerrs == 0) {
aladhd_(nout, path);
}
io___57.ciunit = *nout;
s_wsfe(&io___57);
do_fio(&c__1, "ZPBSV ", (ftnlen)6);
do_fio(&c__1, uplo, (ftnlen)1);
do_fio(&c__1, (char *)&n, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&kd, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&imat, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&k, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&result[k - 1],
(ftnlen)sizeof(doublereal));
e_wsfe();
++nfail;
}
/* L30: */
}
nrun += nt;
L40:
;
}
/* --- Test ZPBSVX --- */
if (! prefac) {
i__5 = kd + 1;
zlaset_("Full", &i__5, &n, &c_b47, &c_b47, &
afac[1], &ldab);
}
zlaset_("Full", &n, nrhs, &c_b47, &c_b47, &x[1], &
lda);
if (iequed > 1 && n > 0) {
/* Equilibrate the matrix if FACT='F' and
EQUED='Y' */
zlaqhb_(uplo, &n, &kd, &a[1], &ldab, &s[1], &
scond, &amax, equed);
}
/* Solve the system and compute the condition
number and error bounds using ZPBSVX. */
s_copy(srnamc_1.srnamt, "ZPBSVX", (ftnlen)6, (
ftnlen)6);
zpbsvx_(fact, uplo, &n, &kd, nrhs, &a[1], &ldab, &
afac[1], &ldab, equed, &s[1], &b[1], &lda,
&x[1], &lda, &rcond, &rwork[1], &rwork[*
nrhs + 1], &work[1], &rwork[(*nrhs << 1)
+ 1], &info);
/* Check the error code from ZPBSVX. */
if (info != izero) {
/* Writing concatenation */
i__7[0] = 1, a__1[0] = fact;
i__7[1] = 1, a__1[1] = uplo;
s_cat(ch__1, a__1, i__7, &c__2, (ftnlen)2);
alaerh_(path, "ZPBSVX", &info, &izero, ch__1,
&n, &n, &kd, &kd, nrhs, &imat, &nfail,
&nerrs, nout);
goto L60;
}
if (info == 0) {
if (! prefac) {
/* Reconstruct matrix from factors and
compute residual. */
zpbt01_(uplo, &n, &kd, &a[1], &ldab, &
afac[1], &ldab, &rwork[(*nrhs <<
1) + 1], result);
k1 = 1;
} else {
k1 = 2;
}
/* Compute residual of the computed solution. */
zlacpy_("Full", &n, nrhs, &bsav[1], &lda, &
work[1], &lda);
zpbt02_(uplo, &n, &kd, nrhs, &asav[1], &ldab,
&x[1], &lda, &work[1], &lda, &rwork[(*
nrhs << 1) + 1], &result[1]);
/* Check solution from generated exact solution. */
if (nofact || prefac && lsame_(equed, "N")) {
zget04_(&n, nrhs, &x[1], &lda, &xact[1], &
lda, &rcondc, &result[2]);
} else {
zget04_(&n, nrhs, &x[1], &lda, &xact[1], &
lda, &roldc, &result[2]);
}
/* Check the error bounds from iterative
refinement. */
zpbt05_(uplo, &n, &kd, nrhs, &asav[1], &ldab,
&b[1], &lda, &x[1], &lda, &xact[1], &
lda, &rwork[1], &rwork[*nrhs + 1], &
result[3]);
} else {
k1 = 6;
}
/* Compare RCOND from ZPBSVX with the computed
value in RCONDC. */
result[5] = dget06_(&rcond, &rcondc);
/* Print information about the tests that did not
pass the threshold. */
for (k = k1; k <= 6; ++k) {
if (result[k - 1] >= *thresh) {
if (nfail == 0 && nerrs == 0) {
aladhd_(nout, path);
}
if (prefac) {
io___60.ciunit = *nout;
s_wsfe(&io___60);
do_fio(&c__1, "ZPBSVX", (ftnlen)6);
do_fio(&c__1, fact, (ftnlen)1);
do_fio(&c__1, uplo, (ftnlen)1);
do_fio(&c__1, (char *)&n, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&kd, (ftnlen)
sizeof(integer));
do_fio(&c__1, equed, (ftnlen)1);
do_fio(&c__1, (char *)&imat, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&k, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&result[k - 1],
(ftnlen)sizeof(doublereal));
e_wsfe();
} else {
io___61.ciunit = *nout;
s_wsfe(&io___61);
do_fio(&c__1, "ZPBSVX", (ftnlen)6);
do_fio(&c__1, fact, (ftnlen)1);
do_fio(&c__1, uplo, (ftnlen)1);
do_fio(&c__1, (char *)&n, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&kd, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&imat, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&k, (ftnlen)
sizeof(integer));
do_fio(&c__1, (char *)&result[k - 1],
(ftnlen)sizeof(doublereal));
e_wsfe();
}
++nfail;
}
/* L50: */
}
nrun = nrun + 7 - k1;
L60:
;
}
/* L70: */
}
L80:
;
}
/* L90: */
}
/* L100: */
}
/* L110: */
}
/* Print a summary of the results. */
alasvm_(path, nout, &nfail, &nrun, &nerrs);
return 0;
/* End of ZDRVPB */
} /* zdrvpb_ */
/* Subroutine */ int zhbev_(char *jobz, char *uplo, integer *n, integer *kd,
doublecomplex *ab, integer *ldab, doublereal *w, doublecomplex *z__,
integer *ldz, doublecomplex *work, doublereal *rwork, integer *info)
{
/* -- LAPACK driver routine (version 3.0) --
Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
Courant Institute, Argonne National Lab, and Rice University
June 30, 1999
Purpose
=======
ZHBEV computes all the eigenvalues and, optionally, eigenvectors of
a complex Hermitian band matrix A.
Arguments
=========
JOBZ (input) CHARACTER*1
= 'N': Compute eigenvalues only;
= 'V': Compute eigenvalues and eigenvectors.
UPLO (input) CHARACTER*1
= 'U': Upper triangle of A is stored;
= 'L': Lower triangle of A is stored.
N (input) INTEGER
The order of the matrix A. N >= 0.
KD (input) INTEGER
The number of superdiagonals of the matrix A if UPLO = 'U',
or the number of subdiagonals if UPLO = 'L'. KD >= 0.
AB (input/output) COMPLEX*16 array, dimension (LDAB, N)
On entry, the upper or lower triangle of the Hermitian band
matrix A, stored in the first KD+1 rows of the array. The
j-th column of A is stored in the j-th column of the array AB
as follows:
if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for max(1,j-kd)<=i<=j;
if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j<=i<=min(n,j+kd).
On exit, AB is overwritten by values generated during the
reduction to tridiagonal form. If UPLO = 'U', the first
superdiagonal and the diagonal of the tridiagonal matrix T
are returned in rows KD and KD+1 of AB, and if UPLO = 'L',
the diagonal and first subdiagonal of T are returned in the
first two rows of AB.
LDAB (input) INTEGER
The leading dimension of the array AB. LDAB >= KD + 1.
W (output) DOUBLE PRECISION array, dimension (N)
If INFO = 0, the eigenvalues in ascending order.
Z (output) COMPLEX*16 array, dimension (LDZ, N)
If JOBZ = 'V', then if INFO = 0, Z contains the orthonormal
eigenvectors of the matrix A, with the i-th column of Z
holding the eigenvector associated with W(i).
If JOBZ = 'N', then Z is not referenced.
LDZ (input) INTEGER
The leading dimension of the array Z. LDZ >= 1, and if
JOBZ = 'V', LDZ >= max(1,N).
WORK (workspace) COMPLEX*16 array, dimension (N)
RWORK (workspace) DOUBLE PRECISION array, dimension (max(1,3*N-2))
INFO (output) INTEGER
= 0: successful exit.
< 0: if INFO = -i, the i-th argument had an illegal value.
> 0: if INFO = i, the algorithm failed to converge; i
off-diagonal elements of an intermediate tridiagonal
form did not converge to zero.
=====================================================================
Test the input parameters.
Parameter adjustments */
/* Table of constant values */
static doublereal c_b11 = 1.;
static integer c__1 = 1;
/* System generated locals */
integer ab_dim1, ab_offset, z_dim1, z_offset, i__1;
doublereal d__1;
/* Builtin functions */
double sqrt(doublereal);
/* Local variables */
static integer inde;
static doublereal anrm;
static integer imax;
static doublereal rmin, rmax;
extern /* Subroutine */ int dscal_(integer *, doublereal *, doublereal *,
integer *);
static doublereal sigma;
extern logical lsame_(char *, char *);
static integer iinfo;
static logical lower, wantz;
extern doublereal dlamch_(char *);
static integer iscale;
static doublereal safmin;
extern doublereal zlanhb_(char *, char *, integer *, integer *,
doublecomplex *, integer *, doublereal *);
extern /* Subroutine */ int xerbla_(char *, integer *);
static doublereal bignum;
extern /* Subroutine */ int dsterf_(integer *, doublereal *, doublereal *,
integer *), zlascl_(char *, integer *, integer *, doublereal *,
doublereal *, integer *, integer *, doublecomplex *, integer *,
integer *), zhbtrd_(char *, char *, integer *, integer *,
doublecomplex *, integer *, doublereal *, doublereal *,
doublecomplex *, integer *, doublecomplex *, integer *);
static integer indrwk;
static doublereal smlnum;
extern /* Subroutine */ int zsteqr_(char *, integer *, doublereal *,
doublereal *, doublecomplex *, integer *, doublereal *, integer *);
static doublereal eps;
#define z___subscr(a_1,a_2) (a_2)*z_dim1 + a_1
#define z___ref(a_1,a_2) z__[z___subscr(a_1,a_2)]
#define ab_subscr(a_1,a_2) (a_2)*ab_dim1 + a_1
#define ab_ref(a_1,a_2) ab[ab_subscr(a_1,a_2)]
ab_dim1 = *ldab;
ab_offset = 1 + ab_dim1 * 1;
ab -= ab_offset;
--w;
z_dim1 = *ldz;
z_offset = 1 + z_dim1 * 1;
z__ -= z_offset;
--work;
--rwork;
/* Function Body */
wantz = lsame_(jobz, "V");
lower = lsame_(uplo, "L");
*info = 0;
if (! (wantz || lsame_(jobz, "N"))) {
*info = -1;
} else if (! (lower || lsame_(uplo, "U"))) {
*info = -2;
} else if (*n < 0) {
*info = -3;
} else if (*kd < 0) {
*info = -4;
} else if (*ldab < *kd + 1) {
*info = -6;
} else if (*ldz < 1 || wantz && *ldz < *n) {
*info = -9;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZHBEV ", &i__1);
return 0;
}
/* Quick return if possible */
if (*n == 0) {
return 0;
}
if (*n == 1) {
if (lower) {
i__1 = ab_subscr(1, 1);
w[1] = ab[i__1].r;
} else {
i__1 = ab_subscr(*kd + 1, 1);
w[1] = ab[i__1].r;
}
if (wantz) {
i__1 = z___subscr(1, 1);
z__[i__1].r = 1., z__[i__1].i = 0.;
}
return 0;
}
/* Get machine constants. */
safmin = dlamch_("Safe minimum");
eps = dlamch_("Precision");
smlnum = safmin / eps;
bignum = 1. / smlnum;
rmin = sqrt(smlnum);
rmax = sqrt(bignum);
/* Scale matrix to allowable range, if necessary. */
anrm = zlanhb_("M", uplo, n, kd, &ab[ab_offset], ldab, &rwork[1]);
iscale = 0;
if (anrm > 0. && anrm < rmin) {
iscale = 1;
sigma = rmin / anrm;
} else if (anrm > rmax) {
iscale = 1;
sigma = rmax / anrm;
}
if (iscale == 1) {
if (lower) {
zlascl_("B", kd, kd, &c_b11, &sigma, n, n, &ab[ab_offset], ldab,
info);
} else {
zlascl_("Q", kd, kd, &c_b11, &sigma, n, n, &ab[ab_offset], ldab,
info);
}
}
/* Call ZHBTRD to reduce Hermitian band matrix to tridiagonal form. */
inde = 1;
zhbtrd_(jobz, uplo, n, kd, &ab[ab_offset], ldab, &w[1], &rwork[inde], &
z__[z_offset], ldz, &work[1], &iinfo);
/* For eigenvalues only, call DSTERF. For eigenvectors, call ZSTEQR. */
if (! wantz) {
dsterf_(n, &w[1], &rwork[inde], info);
} else {
indrwk = inde + *n;
zsteqr_(jobz, n, &w[1], &rwork[inde], &z__[z_offset], ldz, &rwork[
indrwk], info);
}
/* If matrix was scaled, then rescale eigenvalues appropriately. */
if (iscale == 1) {
if (*info == 0) {
imax = *n;
} else {
imax = *info - 1;
}
d__1 = 1. / sigma;
dscal_(&imax, &d__1, &w[1], &c__1);
}
return 0;
/* End of ZHBEV */
} /* zhbev_ */
/* Subroutine */ int zpbt02_(char *uplo, integer *n, integer *kd, integer *
nrhs, doublecomplex *a, integer *lda, doublecomplex *x, integer *ldx,
doublecomplex *b, integer *ldb, doublereal *rwork, doublereal *resid)
{
/* System generated locals */
integer a_dim1, a_offset, b_dim1, b_offset, x_dim1, x_offset, i__1;
doublereal d__1, d__2;
doublecomplex z__1;
/* Local variables */
integer j;
doublereal eps, anorm, bnorm;
doublereal xnorm;
/* -- LAPACK test routine (version 3.1) -- */
/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/* November 2006 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ZPBT02 computes the residual for a solution of a Hermitian banded */
/* system of equations A*x = b: */
/* RESID = norm( B - A*X ) / ( norm(A) * norm(X) * EPS) */
/* where EPS is the machine precision. */
/* Arguments */
/* ========= */
/* UPLO (input) CHARACTER*1 */
/* Specifies whether the upper or lower triangular part of the */
/* Hermitian matrix A is stored: */
/* = 'U': Upper triangular */
/* = 'L': Lower triangular */
/* N (input) INTEGER */
/* The number of rows and columns of the matrix A. N >= 0. */
/* KD (input) INTEGER */
/* The number of super-diagonals of the matrix A if UPLO = 'U', */
/* or the number of sub-diagonals if UPLO = 'L'. KD >= 0. */
/* A (input) COMPLEX*16 array, dimension (LDA,N) */
/* The original Hermitian band matrix A. If UPLO = 'U', the */
/* upper triangular part of A is stored as a band matrix; if */
/* UPLO = 'L', the lower triangular part of A is stored. The */
/* columns of the appropriate triangle are stored in the columns */
/* of A and the diagonals of the triangle are stored in the rows */
/* of A. See ZPBTRF for further details. */
/* LDA (input) INTEGER. */
/* The leading dimension of the array A. LDA >= max(1,KD+1). */
/* X (input) COMPLEX*16 array, dimension (LDX,NRHS) */
/* The computed solution vectors for the system of linear */
/* equations. */
/* LDX (input) INTEGER */
/* The leading dimension of the array X. LDX >= max(1,N). */
/* B (input/output) COMPLEX*16 array, dimension (LDB,NRHS) */
/* On entry, the right hand side vectors for the system of */
/* linear equations. */
/* On exit, B is overwritten with the difference B - A*X. */
/* LDB (input) INTEGER */
/* The leading dimension of the array B. LDB >= max(1,N). */
/* RWORK (workspace) DOUBLE PRECISION array, dimension (N) */
/* RESID (output) DOUBLE PRECISION */
/* The maximum over the number of right hand sides of */
/* norm(B - A*X) / ( norm(A) * norm(X) * EPS ). */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Quick exit if N = 0 or NRHS = 0. */
/* Parameter adjustments */
a_dim1 = *lda;
a_offset = 1 + a_dim1;
a -= a_offset;
x_dim1 = *ldx;
x_offset = 1 + x_dim1;
x -= x_offset;
b_dim1 = *ldb;
b_offset = 1 + b_dim1;
b -= b_offset;
--rwork;
/* Function Body */
if (*n <= 0 || *nrhs <= 0) {
*resid = 0.;
return 0;
}
/* Exit with RESID = 1/EPS if ANORM = 0. */
eps = dlamch_("Epsilon");
anorm = zlanhb_("1", uplo, n, kd, &a[a_offset], lda, &rwork[1]);
if (anorm <= 0.) {
*resid = 1. / eps;
return 0;
}
/* Compute B - A*X */
i__1 = *nrhs;
for (j = 1; j <= i__1; ++j) {
z__1.r = -1., z__1.i = -0.;
zhbmv_(uplo, n, kd, &z__1, &a[a_offset], lda, &x[j * x_dim1 + 1], &
c__1, &c_b1, &b[j * b_dim1 + 1], &c__1);
/* L10: */
}
/* Compute the maximum over the number of right hand sides of */
/* norm( B - A*X ) / ( norm(A) * norm(X) * EPS ) */
*resid = 0.;
i__1 = *nrhs;
for (j = 1; j <= i__1; ++j) {
bnorm = dzasum_(n, &b[j * b_dim1 + 1], &c__1);
xnorm = dzasum_(n, &x[j * x_dim1 + 1], &c__1);
if (xnorm <= 0.) {
*resid = 1. / eps;
} else {
/* Computing MAX */
d__1 = *resid, d__2 = bnorm / anorm / xnorm / eps;
*resid = max(d__1,d__2);
}
/* L20: */
}
return 0;
/* End of ZPBT02 */
} /* zpbt02_ */
/* Subroutine */ int zpbt01_(char *uplo, integer *n, integer *kd,
doublecomplex *a, integer *lda, doublecomplex *afac, integer *ldafac,
doublereal *rwork, doublereal *resid)
{
/* System generated locals */
integer a_dim1, a_offset, afac_dim1, afac_offset, i__1, i__2, i__3, i__4,
i__5;
doublecomplex z__1;
/* Builtin functions */
double d_imag(doublecomplex *);
/* Local variables */
static integer klen;
extern /* Subroutine */ int zher_(char *, integer *, doublereal *,
doublecomplex *, integer *, doublecomplex *, integer *);
static integer i__, j, k;
extern logical lsame_(char *, char *);
static doublereal anorm;
extern /* Double Complex */ VOID zdotc_(doublecomplex *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *);
extern /* Subroutine */ int ztrmv_(char *, char *, char *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *);
static integer kc;
extern doublereal dlamch_(char *);
static integer ml, mu;
extern doublereal zlanhb_(char *, char *, integer *, integer *,
doublecomplex *, integer *, doublereal *);
extern /* Subroutine */ int zdscal_(integer *, doublereal *,
doublecomplex *, integer *);
static doublereal akk, eps;
#define a_subscr(a_1,a_2) (a_2)*a_dim1 + a_1
#define a_ref(a_1,a_2) a[a_subscr(a_1,a_2)]
#define afac_subscr(a_1,a_2) (a_2)*afac_dim1 + a_1
#define afac_ref(a_1,a_2) afac[afac_subscr(a_1,a_2)]
/* -- LAPACK test routine (version 3.0) --
Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
Courant Institute, Argonne National Lab, and Rice University
September 30, 1994
Purpose
=======
ZPBT01 reconstructs a Hermitian positive definite band matrix A from
its L*L' or U'*U factorization and computes the residual
norm( L*L' - A ) / ( N * norm(A) * EPS ) or
norm( U'*U - A ) / ( N * norm(A) * EPS ),
where EPS is the machine epsilon, L' is the conjugate transpose of
L, and U' is the conjugate transpose of U.
Arguments
=========
UPLO (input) CHARACTER*1
Specifies whether the upper or lower triangular part of the
Hermitian matrix A is stored:
= 'U': Upper triangular
= 'L': Lower triangular
N (input) INTEGER
The number of rows and columns of the matrix A. N >= 0.
KD (input) INTEGER
The number of super-diagonals of the matrix A if UPLO = 'U',
or the number of sub-diagonals if UPLO = 'L'. KD >= 0.
A (input) COMPLEX*16 array, dimension (LDA,N)
The original Hermitian band matrix A. If UPLO = 'U', the
upper triangular part of A is stored as a band matrix; if
UPLO = 'L', the lower triangular part of A is stored. The
columns of the appropriate triangle are stored in the columns
of A and the diagonals of the triangle are stored in the rows
of A. See ZPBTRF for further details.
LDA (input) INTEGER.
The leading dimension of the array A. LDA >= max(1,KD+1).
AFAC (input) COMPLEX*16 array, dimension (LDAFAC,N)
The factored form of the matrix A. AFAC contains the factor
L or U from the L*L' or U'*U factorization in band storage
format, as computed by ZPBTRF.
LDAFAC (input) INTEGER
The leading dimension of the array AFAC.
LDAFAC >= max(1,KD+1).
RWORK (workspace) DOUBLE PRECISION array, dimension (N)
RESID (output) DOUBLE PRECISION
If UPLO = 'L', norm(L*L' - A) / ( N * norm(A) * EPS )
If UPLO = 'U', norm(U'*U - A) / ( N * norm(A) * EPS )
=====================================================================
Quick exit if N = 0.
Parameter adjustments */
a_dim1 = *lda;
a_offset = 1 + a_dim1 * 1;
a -= a_offset;
afac_dim1 = *ldafac;
afac_offset = 1 + afac_dim1 * 1;
afac -= afac_offset;
--rwork;
/* Function Body */
if (*n <= 0) {
*resid = 0.;
return 0;
}
/* Exit with RESID = 1/EPS if ANORM = 0. */
eps = dlamch_("Epsilon");
anorm = zlanhb_("1", uplo, n, kd, &a[a_offset], lda, &rwork[1]);
if (anorm <= 0.) {
*resid = 1. / eps;
return 0;
}
/* Check the imaginary parts of the diagonal elements and return with
an error code if any are nonzero. */
if (lsame_(uplo, "U")) {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
if (d_imag(&afac_ref(*kd + 1, j)) != 0.) {
*resid = 1. / eps;
return 0;
}
/* L10: */
}
} else {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
if (d_imag(&afac_ref(1, j)) != 0.) {
*resid = 1. / eps;
return 0;
}
/* L20: */
}
}
/* Compute the product U'*U, overwriting U. */
if (lsame_(uplo, "U")) {
for (k = *n; k >= 1; --k) {
/* Computing MAX */
i__1 = 1, i__2 = *kd + 2 - k;
kc = max(i__1,i__2);
klen = *kd + 1 - kc;
/* Compute the (K,K) element of the result. */
i__1 = klen + 1;
zdotc_(&z__1, &i__1, &afac_ref(kc, k), &c__1, &afac_ref(kc, k), &
c__1);
akk = z__1.r;
i__1 = afac_subscr(*kd + 1, k);
afac[i__1].r = akk, afac[i__1].i = 0.;
/* Compute the rest of column K. */
if (klen > 0) {
i__1 = *ldafac - 1;
ztrmv_("Upper", "Conjugate", "Non-unit", &klen, &afac_ref(*kd
+ 1, k - klen), &i__1, &afac_ref(kc, k), &c__1);
}
/* L30: */
}
/* UPLO = 'L': Compute the product L*L', overwriting L. */
} else {
for (k = *n; k >= 1; --k) {
/* Computing MIN */
i__1 = *kd, i__2 = *n - k;
klen = min(i__1,i__2);
/* Add a multiple of column K of the factor L to each of
columns K+1 through N. */
if (klen > 0) {
i__1 = *ldafac - 1;
zher_("Lower", &klen, &c_b17, &afac_ref(2, k), &c__1, &
afac_ref(1, k + 1), &i__1);
}
/* Scale column K by the diagonal element. */
i__1 = afac_subscr(1, k);
akk = afac[i__1].r;
i__1 = klen + 1;
zdscal_(&i__1, &akk, &afac_ref(1, k), &c__1);
/* L40: */
}
}
/* Compute the difference L*L' - A or U'*U - A. */
if (lsame_(uplo, "U")) {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
/* Computing MAX */
i__2 = 1, i__3 = *kd + 2 - j;
mu = max(i__2,i__3);
i__2 = *kd + 1;
for (i__ = mu; i__ <= i__2; ++i__) {
i__3 = afac_subscr(i__, j);
i__4 = afac_subscr(i__, j);
i__5 = a_subscr(i__, j);
z__1.r = afac[i__4].r - a[i__5].r, z__1.i = afac[i__4].i - a[
i__5].i;
afac[i__3].r = z__1.r, afac[i__3].i = z__1.i;
/* L50: */
}
/* L60: */
}
} else {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
/* Computing MIN */
i__2 = *kd + 1, i__3 = *n - j + 1;
ml = min(i__2,i__3);
i__2 = ml;
for (i__ = 1; i__ <= i__2; ++i__) {
i__3 = afac_subscr(i__, j);
i__4 = afac_subscr(i__, j);
i__5 = a_subscr(i__, j);
z__1.r = afac[i__4].r - a[i__5].r, z__1.i = afac[i__4].i - a[
i__5].i;
afac[i__3].r = z__1.r, afac[i__3].i = z__1.i;
/* L70: */
}
/* L80: */
}
}
/* Compute norm( L*L' - A ) / ( N * norm(A) * EPS ) */
*resid = zlanhb_("1", uplo, n, kd, &afac[afac_offset], ldafac, &rwork[1]);
*resid = *resid / (doublereal) (*n) / anorm / eps;
return 0;
/* End of ZPBT01 */
} /* zpbt01_ */
/* Subroutine */ int zpbsvx_(char *fact, char *uplo, integer *n, integer *kd,
integer *nrhs, doublecomplex *ab, integer *ldab, doublecomplex *afb,
integer *ldafb, char *equed, doublereal *s, doublecomplex *b, integer
*ldb, doublecomplex *x, integer *ldx, doublereal *rcond, doublereal *
ferr, doublereal *berr, doublecomplex *work, doublereal *rwork,
integer *info, ftnlen fact_len, ftnlen uplo_len, ftnlen equed_len)
{
/* System generated locals */
integer ab_dim1, ab_offset, afb_dim1, afb_offset, b_dim1, b_offset,
x_dim1, x_offset, i__1, i__2, i__3, i__4, i__5;
doublereal d__1, d__2;
doublecomplex z__1;
/* Local variables */
static integer i__, j, j1, j2;
static doublereal amax, smin, smax;
extern logical lsame_(char *, char *, ftnlen, ftnlen);
static doublereal scond, anorm;
static logical equil, rcequ, upper;
extern /* Subroutine */ int zcopy_(integer *, doublecomplex *, integer *,
doublecomplex *, integer *);
extern doublereal dlamch_(char *, ftnlen);
static logical nofact;
extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
extern doublereal zlanhb_(char *, char *, integer *, integer *,
doublecomplex *, integer *, doublereal *, ftnlen, ftnlen);
static doublereal bignum;
extern /* Subroutine */ int zlaqhb_(char *, integer *, integer *,
doublecomplex *, integer *, doublereal *, doublereal *,
doublereal *, char *, ftnlen, ftnlen);
static integer infequ;
extern /* Subroutine */ int zpbcon_(char *, integer *, integer *,
doublecomplex *, integer *, doublereal *, doublereal *,
doublecomplex *, doublereal *, integer *, ftnlen), zlacpy_(char *,
integer *, integer *, doublecomplex *, integer *, doublecomplex *
, integer *, ftnlen), zpbequ_(char *, integer *, integer *,
doublecomplex *, integer *, doublereal *, doublereal *,
doublereal *, integer *, ftnlen), zpbrfs_(char *, integer *,
integer *, integer *, doublecomplex *, integer *, doublecomplex *,
integer *, doublecomplex *, integer *, doublecomplex *, integer *
, doublereal *, doublereal *, doublecomplex *, doublereal *,
integer *, ftnlen), zpbtrf_(char *, integer *, integer *,
doublecomplex *, integer *, integer *, ftnlen);
static doublereal smlnum;
extern /* Subroutine */ int zpbtrs_(char *, integer *, integer *, integer
*, doublecomplex *, integer *, doublecomplex *, integer *,
integer *, ftnlen);
/* -- LAPACK driver routine (version 3.0) -- */
/* Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd., */
/* Courant Institute, Argonne National Lab, and Rice University */
/* June 30, 1999 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ZPBSVX uses the Cholesky factorization A = U**H*U or A = L*L**H to */
/* compute the solution to a complex system of linear equations */
/* A * X = B, */
/* where A is an N-by-N Hermitian positive definite band matrix and X */
/* and B are N-by-NRHS matrices. */
/* Error bounds on the solution and a condition estimate are also */
/* provided. */
/* Description */
/* =========== */
/* The following steps are performed: */
/* 1. If FACT = 'E', real scaling factors are computed to equilibrate */
/* the system: */
/* diag(S) * A * diag(S) * inv(diag(S)) * X = diag(S) * B */
/* Whether or not the system will be equilibrated depends on the */
/* scaling of the matrix A, but if equilibration is used, A is */
/* overwritten by diag(S)*A*diag(S) and B by diag(S)*B. */
/* 2. If FACT = 'N' or 'E', the Cholesky decomposition is used to */
/* factor the matrix A (after equilibration if FACT = 'E') as */
/* A = U**H * U, if UPLO = 'U', or */
/* A = L * L**H, if UPLO = 'L', */
/* where U is an upper triangular band matrix, and L is a lower */
/* triangular band matrix. */
/* 3. If the leading i-by-i principal minor is not positive definite, */
/* then the routine returns with INFO = i. Otherwise, the factored */
/* form of A is used to estimate the condition number of the matrix */
/* A. If the reciprocal of the condition number is less than machine */
/* precision, INFO = N+1 is returned as a warning, but the routine */
/* still goes on to solve for X and compute error bounds as */
/* described below. */
/* 4. The system of equations is solved for X using the factored form */
/* of A. */
/* 5. Iterative refinement is applied to improve the computed solution */
/* matrix and calculate error bounds and backward error estimates */
/* for it. */
/* 6. If equilibration was used, the matrix X is premultiplied by */
/* diag(S) so that it solves the original system before */
/* equilibration. */
/* Arguments */
/* ========= */
/* FACT (input) CHARACTER*1 */
/* Specifies whether or not the factored form of the matrix A is */
/* supplied on entry, and if not, whether the matrix A should be */
/* equilibrated before it is factored. */
/* = 'F': On entry, AFB contains the factored form of A. */
/* If EQUED = 'Y', the matrix A has been equilibrated */
/* with scaling factors given by S. AB and AFB will not */
/* be modified. */
/* = 'N': The matrix A will be copied to AFB and factored. */
/* = 'E': The matrix A will be equilibrated if necessary, then */
/* copied to AFB and factored. */
/* UPLO (input) CHARACTER*1 */
/* = 'U': Upper triangle of A is stored; */
/* = 'L': Lower triangle of A is stored. */
/* N (input) INTEGER */
/* The number of linear equations, i.e., the order of the */
/* matrix A. N >= 0. */
/* KD (input) INTEGER */
/* The number of superdiagonals of the matrix A if UPLO = 'U', */
/* or the number of subdiagonals if UPLO = 'L'. KD >= 0. */
/* NRHS (input) INTEGER */
/* The number of right-hand sides, i.e., the number of columns */
/* of the matrices B and X. NRHS >= 0. */
/* AB (input/output) COMPLEX*16 array, dimension (LDAB,N) */
/* On entry, the upper or lower triangle of the Hermitian band */
/* matrix A, stored in the first KD+1 rows of the array, except */
/* if FACT = 'F' and EQUED = 'Y', then A must contain the */
/* equilibrated matrix diag(S)*A*diag(S). The j-th column of A */
/* is stored in the j-th column of the array AB as follows: */
/* if UPLO = 'U', AB(KD+1+i-j,j) = A(i,j) for max(1,j-KD)<=i<=j; */
/* if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j<=i<=min(N,j+KD). */
/* See below for further details. */
/* On exit, if FACT = 'E' and EQUED = 'Y', A is overwritten by */
/* diag(S)*A*diag(S). */
/* LDAB (input) INTEGER */
/* The leading dimension of the array A. LDAB >= KD+1. */
/* AFB (input or output) COMPLEX*16 array, dimension (LDAFB,N) */
/* If FACT = 'F', then AFB is an input argument and on entry */
/* contains the triangular factor U or L from the Cholesky */
/* factorization A = U**H*U or A = L*L**H of the band matrix */
/* A, in the same storage format as A (see AB). If EQUED = 'Y', */
/* then AFB is the factored form of the equilibrated matrix A. */
/* If FACT = 'N', then AFB is an output argument and on exit */
/* returns the triangular factor U or L from the Cholesky */
/* factorization A = U**H*U or A = L*L**H. */
/* If FACT = 'E', then AFB is an output argument and on exit */
/* returns the triangular factor U or L from the Cholesky */
/* factorization A = U**H*U or A = L*L**H of the equilibrated */
/* matrix A (see the description of A for the form of the */
/* equilibrated matrix). */
/* LDAFB (input) INTEGER */
/* The leading dimension of the array AFB. LDAFB >= KD+1. */
/* EQUED (input or output) CHARACTER*1 */
/* Specifies the form of equilibration that was done. */
/* = 'N': No equilibration (always true if FACT = 'N'). */
/* = 'Y': Equilibration was done, i.e., A has been replaced by */
/* diag(S) * A * diag(S). */
/* EQUED is an input argument if FACT = 'F'; otherwise, it is an */
/* output argument. */
/* S (input or output) DOUBLE PRECISION array, dimension (N) */
/* The scale factors for A; not accessed if EQUED = 'N'. S is */
/* an input argument if FACT = 'F'; otherwise, S is an output */
/* argument. If FACT = 'F' and EQUED = 'Y', each element of S */
/* must be positive. */
/* B (input/output) COMPLEX*16 array, dimension (LDB,NRHS) */
/* On entry, the N-by-NRHS right hand side matrix B. */
/* On exit, if EQUED = 'N', B is not modified; if EQUED = 'Y', */
/* B is overwritten by diag(S) * B. */
/* LDB (input) INTEGER */
/* The leading dimension of the array B. LDB >= max(1,N). */
/* X (output) COMPLEX*16 array, dimension (LDX,NRHS) */
/* If INFO = 0 or INFO = N+1, the N-by-NRHS solution matrix X to */
/* the original system of equations. Note that if EQUED = 'Y', */
/* A and B are modified on exit, and the solution to the */
/* equilibrated system is inv(diag(S))*X. */
/* LDX (input) INTEGER */
/* The leading dimension of the array X. LDX >= max(1,N). */
/* RCOND (output) DOUBLE PRECISION */
/* The estimate of the reciprocal condition number of the matrix */
/* A after equilibration (if done). If RCOND is less than the */
/* machine precision (in particular, if RCOND = 0), the matrix */
/* is singular to working precision. This condition is */
/* indicated by a return code of INFO > 0. */
/* FERR (output) DOUBLE PRECISION array, dimension (NRHS) */
/* The estimated forward error bound for each solution vector */
/* X(j) (the j-th column of the solution matrix X). */
/* If XTRUE is the true solution corresponding to X(j), FERR(j) */
/* is an estimated upper bound for the magnitude of the largest */
/* element in (X(j) - XTRUE) divided by the magnitude of the */
/* largest element in X(j). The estimate is as reliable as */
/* the estimate for RCOND, and is almost always a slight */
/* overestimate of the true error. */
/* BERR (output) DOUBLE PRECISION array, dimension (NRHS) */
/* The componentwise relative backward error of each solution */
/* vector X(j) (i.e., the smallest relative change in */
/* any element of A or B that makes X(j) an exact solution). */
/* WORK (workspace) COMPLEX*16 array, dimension (2*N) */
/* RWORK (workspace) DOUBLE PRECISION array, dimension (N) */
/* INFO (output) INTEGER */
/* = 0: successful exit */
/* < 0: if INFO = -i, the i-th argument had an illegal value */
/* > 0: if INFO = i, and i is */
/* <= N: the leading minor of order i of A is */
/* not positive definite, so the factorization */
/* could not be completed, and the solution has not */
/* been computed. RCOND = 0 is returned. */
/* = N+1: U is nonsingular, but RCOND is less than machine */
/* precision, meaning that the matrix is singular */
/* to working precision. Nevertheless, the */
/* solution and error bounds are computed because */
/* there are a number of situations where the */
/* computed solution can be more accurate than the */
/* value of RCOND would suggest. */
/* Further Details */
/* =============== */
/* The band storage scheme is illustrated by the following example, when */
/* N = 6, KD = 2, and UPLO = 'U': */
/* Two-dimensional storage of the Hermitian matrix A: */
/* a11 a12 a13 */
/* a22 a23 a24 */
/* a33 a34 a35 */
/* a44 a45 a46 */
/* a55 a56 */
/* (aij=conjg(aji)) a66 */
/* Band storage of the upper triangle of A: */
/* * * a13 a24 a35 a46 */
/* * a12 a23 a34 a45 a56 */
/* a11 a22 a33 a44 a55 a66 */
/* Similarly, if UPLO = 'L' the format of A is as follows: */
/* a11 a22 a33 a44 a55 a66 */
/* a21 a32 a43 a54 a65 * */
/* a31 a42 a53 a64 * * */
/* Array elements marked * are not used by the routine. */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Parameter adjustments */
ab_dim1 = *ldab;
ab_offset = 1 + ab_dim1;
ab -= ab_offset;
afb_dim1 = *ldafb;
afb_offset = 1 + afb_dim1;
afb -= afb_offset;
--s;
b_dim1 = *ldb;
b_offset = 1 + b_dim1;
b -= b_offset;
x_dim1 = *ldx;
x_offset = 1 + x_dim1;
x -= x_offset;
--ferr;
--berr;
--work;
--rwork;
/* Function Body */
*info = 0;
nofact = lsame_(fact, "N", (ftnlen)1, (ftnlen)1);
equil = lsame_(fact, "E", (ftnlen)1, (ftnlen)1);
upper = lsame_(uplo, "U", (ftnlen)1, (ftnlen)1);
if (nofact || equil) {
*(unsigned char *)equed = 'N';
rcequ = FALSE_;
} else {
rcequ = lsame_(equed, "Y", (ftnlen)1, (ftnlen)1);
smlnum = dlamch_("Safe minimum", (ftnlen)12);
bignum = 1. / smlnum;
}
/* Test the input parameters. */
if (! nofact && ! equil && ! lsame_(fact, "F", (ftnlen)1, (ftnlen)1)) {
*info = -1;
} else if (! upper && ! lsame_(uplo, "L", (ftnlen)1, (ftnlen)1)) {
*info = -2;
} else if (*n < 0) {
*info = -3;
} else if (*kd < 0) {
*info = -4;
} else if (*nrhs < 0) {
*info = -5;
} else if (*ldab < *kd + 1) {
*info = -7;
} else if (*ldafb < *kd + 1) {
*info = -9;
} else if (lsame_(fact, "F", (ftnlen)1, (ftnlen)1) && ! (rcequ || lsame_(
equed, "N", (ftnlen)1, (ftnlen)1))) {
*info = -10;
} else {
if (rcequ) {
smin = bignum;
smax = 0.;
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
/* Computing MIN */
d__1 = smin, d__2 = s[j];
smin = min(d__1,d__2);
/* Computing MAX */
d__1 = smax, d__2 = s[j];
smax = max(d__1,d__2);
/* L10: */
}
if (smin <= 0.) {
*info = -11;
} else if (*n > 0) {
scond = max(smin,smlnum) / min(smax,bignum);
} else {
scond = 1.;
}
}
if (*info == 0) {
if (*ldb < max(1,*n)) {
*info = -13;
} else if (*ldx < max(1,*n)) {
*info = -15;
}
}
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZPBSVX", &i__1, (ftnlen)6);
return 0;
}
if (equil) {
/* Compute row and column scalings to equilibrate the matrix A. */
zpbequ_(uplo, n, kd, &ab[ab_offset], ldab, &s[1], &scond, &amax, &
infequ, (ftnlen)1);
if (infequ == 0) {
/* Equilibrate the matrix. */
zlaqhb_(uplo, n, kd, &ab[ab_offset], ldab, &s[1], &scond, &amax,
equed, (ftnlen)1, (ftnlen)1);
rcequ = lsame_(equed, "Y", (ftnlen)1, (ftnlen)1);
}
}
/* Scale the right-hand side. */
if (rcequ) {
i__1 = *nrhs;
for (j = 1; j <= i__1; ++j) {
i__2 = *n;
for (i__ = 1; i__ <= i__2; ++i__) {
i__3 = i__ + j * b_dim1;
i__4 = i__;
i__5 = i__ + j * b_dim1;
z__1.r = s[i__4] * b[i__5].r, z__1.i = s[i__4] * b[i__5].i;
b[i__3].r = z__1.r, b[i__3].i = z__1.i;
/* L20: */
}
/* L30: */
}
}
if (nofact || equil) {
/* Compute the Cholesky factorization A = U'*U or A = L*L'. */
if (upper) {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
/* Computing MAX */
i__2 = j - *kd;
j1 = max(i__2,1);
i__2 = j - j1 + 1;
zcopy_(&i__2, &ab[*kd + 1 - j + j1 + j * ab_dim1], &c__1, &
afb[*kd + 1 - j + j1 + j * afb_dim1], &c__1);
/* L40: */
}
} else {
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
/* Computing MIN */
i__2 = j + *kd;
j2 = min(i__2,*n);
i__2 = j2 - j + 1;
zcopy_(&i__2, &ab[j * ab_dim1 + 1], &c__1, &afb[j * afb_dim1
+ 1], &c__1);
/* L50: */
}
}
zpbtrf_(uplo, n, kd, &afb[afb_offset], ldafb, info, (ftnlen)1);
/* Return if INFO is non-zero. */
if (*info != 0) {
if (*info > 0) {
*rcond = 0.;
}
return 0;
}
}
/* Compute the norm of the matrix A. */
anorm = zlanhb_("1", uplo, n, kd, &ab[ab_offset], ldab, &rwork[1], (
ftnlen)1, (ftnlen)1);
/* Compute the reciprocal of the condition number of A. */
zpbcon_(uplo, n, kd, &afb[afb_offset], ldafb, &anorm, rcond, &work[1], &
rwork[1], info, (ftnlen)1);
/* Set INFO = N+1 if the matrix is singular to working precision. */
if (*rcond < dlamch_("Epsilon", (ftnlen)7)) {
*info = *n + 1;
}
/* Compute the solution matrix X. */
zlacpy_("Full", n, nrhs, &b[b_offset], ldb, &x[x_offset], ldx, (ftnlen)4);
zpbtrs_(uplo, n, kd, nrhs, &afb[afb_offset], ldafb, &x[x_offset], ldx,
info, (ftnlen)1);
/* Use iterative refinement to improve the computed solution and */
/* compute error bounds and backward error estimates for it. */
zpbrfs_(uplo, n, kd, nrhs, &ab[ab_offset], ldab, &afb[afb_offset], ldafb,
&b[b_offset], ldb, &x[x_offset], ldx, &ferr[1], &berr[1], &work[1]
, &rwork[1], info, (ftnlen)1);
/* Transform the solution matrix X to a solution of the original */
/* system. */
if (rcequ) {
i__1 = *nrhs;
for (j = 1; j <= i__1; ++j) {
i__2 = *n;
for (i__ = 1; i__ <= i__2; ++i__) {
i__3 = i__ + j * x_dim1;
i__4 = i__;
i__5 = i__ + j * x_dim1;
z__1.r = s[i__4] * x[i__5].r, z__1.i = s[i__4] * x[i__5].i;
x[i__3].r = z__1.r, x[i__3].i = z__1.i;
/* L60: */
}
/* L70: */
}
i__1 = *nrhs;
for (j = 1; j <= i__1; ++j) {
ferr[j] /= scond;
/* L80: */
}
}
return 0;
/* End of ZPBSVX */
} /* zpbsvx_ */
/* Subroutine */ int zhbevd_(char *jobz, char *uplo, integer *n, integer *kd,
doublecomplex *ab, integer *ldab, doublereal *w, doublecomplex *z__,
integer *ldz, doublecomplex *work, integer *lwork, doublereal *rwork,
integer *lrwork, integer *iwork, integer *liwork, integer *info)
{
/* -- LAPACK driver routine (version 3.0) --
Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
Courant Institute, Argonne National Lab, and Rice University
June 30, 1999
Purpose
=======
ZHBEVD computes all the eigenvalues and, optionally, eigenvectors of
a complex Hermitian band matrix A. If eigenvectors are desired, it
uses a divide and conquer algorithm.
The divide and conquer algorithm makes very mild assumptions about
floating point arithmetic. It will work on machines with a guard
digit in add/subtract, or on those binary machines without guard
digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or
Cray-2. It could conceivably fail on hexadecimal or decimal machines
without guard digits, but we know of none.
Arguments
=========
JOBZ (input) CHARACTER*1
= 'N': Compute eigenvalues only;
= 'V': Compute eigenvalues and eigenvectors.
UPLO (input) CHARACTER*1
= 'U': Upper triangle of A is stored;
= 'L': Lower triangle of A is stored.
N (input) INTEGER
The order of the matrix A. N >= 0.
KD (input) INTEGER
The number of superdiagonals of the matrix A if UPLO = 'U',
or the number of subdiagonals if UPLO = 'L'. KD >= 0.
AB (input/output) COMPLEX*16 array, dimension (LDAB, N)
On entry, the upper or lower triangle of the Hermitian band
matrix A, stored in the first KD+1 rows of the array. The
j-th column of A is stored in the j-th column of the array AB
as follows:
if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for max(1,j-kd)<=i<=j;
if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j<=i<=min(n,j+kd).
On exit, AB is overwritten by values generated during the
reduction to tridiagonal form. If UPLO = 'U', the first
superdiagonal and the diagonal of the tridiagonal matrix T
are returned in rows KD and KD+1 of AB, and if UPLO = 'L',
the diagonal and first subdiagonal of T are returned in the
first two rows of AB.
LDAB (input) INTEGER
The leading dimension of the array AB. LDAB >= KD + 1.
W (output) DOUBLE PRECISION array, dimension (N)
If INFO = 0, the eigenvalues in ascending order.
Z (output) COMPLEX*16 array, dimension (LDZ, N)
If JOBZ = 'V', then if INFO = 0, Z contains the orthonormal
eigenvectors of the matrix A, with the i-th column of Z
holding the eigenvector associated with W(i).
If JOBZ = 'N', then Z is not referenced.
LDZ (input) INTEGER
The leading dimension of the array Z. LDZ >= 1, and if
JOBZ = 'V', LDZ >= max(1,N).
WORK (workspace/output) COMPLEX*16 array, dimension (LWORK)
On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
LWORK (input) INTEGER
The dimension of the array WORK.
If N <= 1, LWORK must be at least 1.
If JOBZ = 'N' and N > 1, LWORK must be at least N.
If JOBZ = 'V' and N > 1, LWORK must be at least 2*N**2.
If LWORK = -1, then a workspace query is assumed; the routine
only calculates the optimal size of the WORK array, returns
this value as the first entry of the WORK array, and no error
message related to LWORK is issued by XERBLA.
RWORK (workspace/output) DOUBLE PRECISION array,
dimension (LRWORK)
On exit, if INFO = 0, RWORK(1) returns the optimal LRWORK.
LRWORK (input) INTEGER
The dimension of array RWORK.
If N <= 1, LRWORK must be at least 1.
If JOBZ = 'N' and N > 1, LRWORK must be at least N.
If JOBZ = 'V' and N > 1, LRWORK must be at least
1 + 5*N + 2*N**2.
If LRWORK = -1, then a workspace query is assumed; the
routine only calculates the optimal size of the RWORK array,
returns this value as the first entry of the RWORK array, and
no error message related to LRWORK is issued by XERBLA.
IWORK (workspace/output) INTEGER array, dimension (LIWORK)
On exit, if INFO = 0, IWORK(1) returns the optimal LIWORK.
LIWORK (input) INTEGER
The dimension of array IWORK.
If JOBZ = 'N' or N <= 1, LIWORK must be at least 1.
If JOBZ = 'V' and N > 1, LIWORK must be at least 3 + 5*N .
If LIWORK = -1, then a workspace query is assumed; the
routine only calculates the optimal size of the IWORK array,
returns this value as the first entry of the IWORK array, and
no error message related to LIWORK is issued by XERBLA.
INFO (output) INTEGER
= 0: successful exit.
< 0: if INFO = -i, the i-th argument had an illegal value.
> 0: if INFO = i, the algorithm failed to converge; i
off-diagonal elements of an intermediate tridiagonal
form did not converge to zero.
=====================================================================
Test the input parameters.
Parameter adjustments */
/* Table of constant values */
static doublecomplex c_b1 = {0.,0.};
static doublecomplex c_b2 = {1.,0.};
static doublereal c_b13 = 1.;
static integer c__1 = 1;
/* System generated locals */
integer ab_dim1, ab_offset, z_dim1, z_offset, i__1;
doublereal d__1;
/* Builtin functions */
double sqrt(doublereal);
/* Local variables */
static integer inde;
static doublereal anrm;
static integer imax;
static doublereal rmin, rmax;
static integer llwk2;
extern /* Subroutine */ int dscal_(integer *, doublereal *, doublereal *,
integer *);
static doublereal sigma;
extern logical lsame_(char *, char *);
static integer iinfo;
extern /* Subroutine */ int zgemm_(char *, char *, integer *, integer *,
integer *, doublecomplex *, doublecomplex *, integer *,
doublecomplex *, integer *, doublecomplex *, doublecomplex *,
integer *);
static integer lwmin;
static logical lower;
static integer llrwk;
static logical wantz;
static integer indwk2;
extern doublereal dlamch_(char *);
static integer iscale;
static doublereal safmin;
extern doublereal zlanhb_(char *, char *, integer *, integer *,
doublecomplex *, integer *, doublereal *);
extern /* Subroutine */ int xerbla_(char *, integer *);
static doublereal bignum;
extern /* Subroutine */ int dsterf_(integer *, doublereal *, doublereal *,
integer *), zlascl_(char *, integer *, integer *, doublereal *,
doublereal *, integer *, integer *, doublecomplex *, integer *,
integer *), zstedc_(char *, integer *, doublereal *,
doublereal *, doublecomplex *, integer *, doublecomplex *,
integer *, doublereal *, integer *, integer *, integer *, integer
*), zhbtrd_(char *, char *, integer *, integer *,
doublecomplex *, integer *, doublereal *, doublereal *,
doublecomplex *, integer *, doublecomplex *, integer *);
static integer indwrk, liwmin;
extern /* Subroutine */ int zlacpy_(char *, integer *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *);
static integer lrwmin;
static doublereal smlnum;
static logical lquery;
static doublereal eps;
#define z___subscr(a_1,a_2) (a_2)*z_dim1 + a_1
#define z___ref(a_1,a_2) z__[z___subscr(a_1,a_2)]
#define ab_subscr(a_1,a_2) (a_2)*ab_dim1 + a_1
#define ab_ref(a_1,a_2) ab[ab_subscr(a_1,a_2)]
ab_dim1 = *ldab;
ab_offset = 1 + ab_dim1 * 1;
ab -= ab_offset;
--w;
z_dim1 = *ldz;
z_offset = 1 + z_dim1 * 1;
z__ -= z_offset;
--work;
--rwork;
--iwork;
/* Function Body */
wantz = lsame_(jobz, "V");
lower = lsame_(uplo, "L");
lquery = *lwork == -1 || *liwork == -1 || *lrwork == -1;
*info = 0;
if (*n <= 1) {
lwmin = 1;
lrwmin = 1;
liwmin = 1;
} else {
if (wantz) {
/* Computing 2nd power */
i__1 = *n;
lwmin = i__1 * i__1 << 1;
/* Computing 2nd power */
i__1 = *n;
lrwmin = *n * 5 + 1 + (i__1 * i__1 << 1);
liwmin = *n * 5 + 3;
} else {
lwmin = *n;
lrwmin = *n;
liwmin = 1;
}
}
if (! (wantz || lsame_(jobz, "N"))) {
*info = -1;
} else if (! (lower || lsame_(uplo, "U"))) {
*info = -2;
} else if (*n < 0) {
*info = -3;
} else if (*kd < 0) {
*info = -4;
} else if (*ldab < *kd + 1) {
*info = -6;
} else if (*ldz < 1 || wantz && *ldz < *n) {
*info = -9;
} else if (*lwork < lwmin && ! lquery) {
*info = -11;
} else if (*lrwork < lrwmin && ! lquery) {
*info = -13;
} else if (*liwork < liwmin && ! lquery) {
*info = -15;
}
if (*info == 0) {
work[1].r = (doublereal) lwmin, work[1].i = 0.;
rwork[1] = (doublereal) lrwmin;
iwork[1] = liwmin;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZHBEVD", &i__1);
return 0;
} else if (lquery) {
return 0;
}
/* Quick return if possible */
if (*n == 0) {
return 0;
}
if (*n == 1) {
i__1 = ab_subscr(1, 1);
w[1] = ab[i__1].r;
if (wantz) {
i__1 = z___subscr(1, 1);
z__[i__1].r = 1., z__[i__1].i = 0.;
}
return 0;
}
/* Get machine constants. */
safmin = dlamch_("Safe minimum");
eps = dlamch_("Precision");
smlnum = safmin / eps;
bignum = 1. / smlnum;
rmin = sqrt(smlnum);
rmax = sqrt(bignum);
/* Scale matrix to allowable range, if necessary. */
anrm = zlanhb_("M", uplo, n, kd, &ab[ab_offset], ldab, &rwork[1]);
iscale = 0;
if (anrm > 0. && anrm < rmin) {
iscale = 1;
sigma = rmin / anrm;
} else if (anrm > rmax) {
iscale = 1;
sigma = rmax / anrm;
}
if (iscale == 1) {
if (lower) {
zlascl_("B", kd, kd, &c_b13, &sigma, n, n, &ab[ab_offset], ldab,
info);
} else {
zlascl_("Q", kd, kd, &c_b13, &sigma, n, n, &ab[ab_offset], ldab,
info);
}
}
/* Call ZHBTRD to reduce Hermitian band matrix to tridiagonal form. */
inde = 1;
indwrk = inde + *n;
indwk2 = *n * *n + 1;
llwk2 = *lwork - indwk2 + 1;
llrwk = *lrwork - indwrk + 1;
zhbtrd_(jobz, uplo, n, kd, &ab[ab_offset], ldab, &w[1], &rwork[inde], &
z__[z_offset], ldz, &work[1], &iinfo);
/* For eigenvalues only, call DSTERF. For eigenvectors, call ZSTEDC. */
if (! wantz) {
dsterf_(n, &w[1], &rwork[inde], info);
} else {
zstedc_("I", n, &w[1], &rwork[inde], &work[1], n, &work[indwk2], &
llwk2, &rwork[indwrk], &llrwk, &iwork[1], liwork, info);
zgemm_("N", "N", n, n, n, &c_b2, &z__[z_offset], ldz, &work[1], n, &
c_b1, &work[indwk2], n);
zlacpy_("A", n, n, &work[indwk2], n, &z__[z_offset], ldz);
}
/* If matrix was scaled, then rescale eigenvalues appropriately. */
if (iscale == 1) {
if (*info == 0) {
imax = *n;
} else {
imax = *info - 1;
}
d__1 = 1. / sigma;
dscal_(&imax, &d__1, &w[1], &c__1);
}
work[1].r = (doublereal) lwmin, work[1].i = 0.;
rwork[1] = (doublereal) lrwmin;
iwork[1] = liwmin;
return 0;
/* End of ZHBEVD */
} /* zhbevd_ */
