void DenseMatrix<T>::_evd_lapack (DenseVector<T> & lambda_real,
DenseVector<T> & lambda_imag)
{
// The calling sequence for dgeev is:
// DGEEVX( BALANC, JOBVL, JOBVR, SENSE, N, A, LDA, WR, WI, VL, LDVL, VR,
// LDVR, ILO, IHI, SCALE, ABNRM, RCONDE, RCONDV, WORK, LWORK, IWORK, INFO )
// BALANC (input) CHARACTER*1
// Indicates how the input matrix should be diagonally scaled
// and/or permuted to improve the conditioning of its
// eigenvalues.
// = 'N': Do not diagonally scale or permute;
char BALANC = 'N';
// JOBVL (input) CHARACTER*1
// = 'N': left eigenvectors of A are not computed;
// = 'V': left eigenvectors of A are computed.
char JOBVL = 'N';
// JOBVR (input) CHARACTER*1
// = 'N': right eigenvectors of A are not computed;
// = 'V': right eigenvectors of A are computed.
char JOBVR = 'N';
// SENSE (input) CHARACTER*1
// Determines which reciprocal condition numbers are computed.
// = 'N': None are computed;
// = 'E': Computed for eigenvalues only;
// = 'V': Computed for right eigenvectors only;
// = 'B': Computed for eigenvalues and right eigenvectors.
char SENSE = 'N';
// N (input) int *
// The number of rows/cols of the matrix A. N >= 0.
libmesh_assert( this->m() == this->n() );
int N = this->m();
// A (input/output) DOUBLE PRECISION array, dimension (LDA,N)
// On entry, the N-by-N matrix A.
// On exit, A has been overwritten.
// Here, we pass &(_val[0]).
// LDA (input) int *
// The leading dimension of the array A. LDA >= max(1,N).
int LDA = N;
// WR (output) DOUBLE PRECISION array, dimension (N)
// WI (output) DOUBLE PRECISION array, dimension (N)
// WR and WI contain the real and imaginary parts,
// respectively, of the computed eigenvalues. Complex
// conjugate pairs of eigenvalues appear consecutively
// with the eigenvalue having the positive imaginary part
// first.
lambda_real.resize(N);
lambda_imag.resize(N);
// VL (output) DOUBLE PRECISION array, dimension (LDVL,N)
// If JOBVL = 'V', the left eigenvectors u(j) are stored one
// after another in the columns of VL, in the same order
// as their eigenvalues.
// If JOBVL = 'N', VL is not referenced.
// If the j-th eigenvalue is real, then u(j) = VL(:,j),
// the j-th column of VL.
// If the j-th and (j+1)-st eigenvalues form a complex
// conjugate pair, then u(j) = VL(:,j) + i*VL(:,j+1) and
// u(j+1) = VL(:,j) - i*VL(:,j+1).
// Just set to NULL here.
// LDVL (input) INTEGER
// The leading dimension of the array VL. LDVL >= 1; if
// JOBVL = 'V', LDVL >= N.
int LDVL = 1;
// VR (output) DOUBLE PRECISION array, dimension (LDVR,N)
// If JOBVR = 'V', the right eigenvectors v(j) are stored one
// after another in the columns of VR, in the same order
// as their eigenvalues.
// If JOBVR = 'N', VR is not referenced.
// If the j-th eigenvalue is real, then v(j) = VR(:,j),
// the j-th column of VR.
// If the j-th and (j+1)-st eigenvalues form a complex
// conjugate pair, then v(j) = VR(:,j) + i*VR(:,j+1) and
// v(j+1) = VR(:,j) - i*VR(:,j+1).
// Just set to NULL here.
// LDVR (input) INTEGER
// The leading dimension of the array VR. LDVR >= 1; if
// JOBVR = 'V', LDVR >= N.
int LDVR = 1;
// Outputs (unused)
int ILO = 0;
int IHI = 0;
std::vector<T> SCALE(N);
T ABNRM;
std::vector<T> RCONDE(N);
std::vector<T> RCONDV(N);
// WORK (workspace/output) DOUBLE PRECISION array, dimension (MAX(1,LWORK))
// On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
//
// LWORK (input) INTEGER
// The dimension of the array WORK.
int LWORK = 3*N;
std::vector<T> WORK( LWORK );
// IWORK (workspace) INTEGER array, dimension (2*N-2)
// If SENSE = 'N' or 'E', not referenced.
// Just set to NULL
// INFO (output) INTEGER
// = 0: successful exit
// < 0: if INFO = -i, the i-th argument had an illegal value.
// > 0: if INFO = i, the QR algorithm failed to compute all the
// eigenvalues, and no eigenvectors or condition numbers
// have been computed; elements 1:ILO-1 and i+1:N of WR
// and WI contain eigenvalues which have converged.
int INFO = 0;
// Get references to raw data
std::vector<T> & lambda_real_val = lambda_real.get_values();
std::vector<T> & lambda_imag_val = lambda_imag.get_values();
// Ready to call the actual factorization routine through SLEPc's interface
LAPACKgeevx_( &BALANC, &JOBVL, &JOBVR, &SENSE, &N, &(_val[0]), &LDA, &lambda_real_val[0],
&lambda_imag_val[0], libmesh_nullptr, &LDVL, libmesh_nullptr, &LDVR, &ILO, &IHI, &SCALE[0], &ABNRM,
&RCONDE[0], &RCONDV[0], &WORK[0], &LWORK, libmesh_nullptr, &INFO );
// Check return value for errors
if (INFO != 0)
libmesh_error_msg("INFO=" << INFO << ", Error during Lapack eigenvalue calculation!");
}
void setup (int N, const Parameter ¶m, Array<double, 1> &WR, Array<double,2> &ev, Array<double,2> &evInv)
{
int Nm1 = N;
int i;
Array<double, 1> x;
Array<double, 2> D;
Array<double, 1> r;
Array<double, 2> Dsec;
Array<double, 1> XX;
Array<double, 1> YY;
Array<double, 2> A(N,N);
Array<double, 2> B(N,N);
Array<int, 1> IPIV(Nm1);
char BALANC[1];
char JOBVL[1];
char JOBVR[1];
char SENSE[1];
int LDA;
int LDVL;
int LDVR;
int NRHS;
int LDB;
int INFO;
//resize output arrays
WR.resize(N);
ev.resize(N, N);
evInv.resize(N, N);
// parameters for DGEEVX
Array<double, 1> WI(Nm1); // WR(Nm1),
// The real and imaginary part of the eig.values
Array<double, 2> VL(N, N);
Array<double, 2> VR(Nm1,Nm1); //VR(Nm1,Nm1);
// The left and rigth eigenvectors
int ILO, IHI; // Info on the balanced output matrix
Array<double, 1> SCALE(Nm1); // Scaling factors applied for balancing
double ABNRM; // 1-Norm of the balanced matrix
Array<double, 1> RCONDE(Nm1);
// the reciprocal cond. numb of the respective eig.val
Array<double, 1> RCONDV(Nm1);
// the reciprocal cond. numb of the respective eig.vec
int LWORK = (N+1)*(N+7); // Depending on SENSE
Array<double, 1> WORK(LWORK);
Array<int, 1> IWORK(2*(N+1)-2);
// Compute the Chebyshev differensiation matrix and D*D
// cheb(N, x, D);
cheb(N, x, D);
Dsec.resize(D.shape());
MatrixMatrixMultiply(D, D, Dsec);
// Compute the 1. and 2. derivatives of the transformations
XYmat(N, param, XX, YY, r);
// Set up the full timepropagation matrix A
// dy/dt = - i A y
Range range(1, N); //Dsec and D have range 0, N+1.
//We don't want the edge points in A
A = XX(tensor::i) * Dsec(range, range) + YY(tensor::i) * D(range, range);
//Transpose A
for (int i=0; i<A.extent(0); i++)
{
for (int j=0; j<i; j++)
{
double t = A(i,j);
A(i,j) = A(j, i);
A(j,i) = t;
}
}
// Add radialpart of non-time dependent potential here
/* 2D radial
for (int i=0; i<A.extent(0); i++)
{
A(i, i) += 0.25 / (r(i)*r(i));
}
*/
// Compute eigen decomposition
BALANC[0] ='B';
JOBVL[0] ='V';
JOBVR[0] ='V';
SENSE[0] ='B';
LDA = Nm1;
LDVL = Nm1;
LDVR = Nm1;
FORTRAN_NAME(dgeevx)(BALANC, JOBVL, JOBVR, SENSE, &Nm1,
A.data(), &LDA, WR.data(), WI.data(),
VL.data(), &LDVL, VR.data(), &LDVR, &ILO, &IHI,
SCALE.data(), &ABNRM,
RCONDE.data(), RCONDV.data(), WORK.data(), &LWORK,
IWORK.data(), &INFO);
// Compute the inverse of the eigen vector matrix
NRHS = Nm1;
evInv = VR ;// VL;
LDB = LDA;
B = 0.0;
for (i=0; i<Nm1; i++) B(i,i) = 1.0;
FORTRAN_NAME(dgesv)(&Nm1, &NRHS, evInv.data(), &LDA, IPIV.data(), B.data(), &LDB, &INFO);
ev = VR(tensor::j, tensor::i); //Transpose
evInv = B(tensor::j, tensor::i); //Transpose
//cout << "Eigenvectors (right): " << ev << endl;
//cout << "Eigenvectors (inv): " << evInv << endl;
//printf(" Done inverse, INFO = %d \n", INFO);
} // done
/* Subroutine */ int zgeevx_(char *balanc, char *jobvl, char *jobvr, char *
sense, integer *n, doublecomplex *a, integer *lda, doublecomplex *w,
doublecomplex *vl, integer *ldvl, doublecomplex *vr, integer *ldvr,
integer *ilo, integer *ihi, doublereal *scale, doublereal *abnrm,
doublereal *rconde, doublereal *rcondv, doublecomplex *work, integer *
lwork, doublereal *rwork, integer *info)
{
/* -- LAPACK driver routine (version 2.0) --
Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
Courant Institute, Argonne National Lab, and Rice University
September 30, 1994
Purpose
=======
ZGEEVX computes for an N-by-N complex nonsymmetric matrix A, the
eigenvalues and, optionally, the left and/or right eigenvectors.
Optionally also, it computes a balancing transformation to improve
the conditioning of the eigenvalues and eigenvectors (ILO, IHI,
SCALE, and ABNRM), reciprocal condition numbers for the eigenvalues
(RCONDE), and reciprocal condition numbers for the right
eigenvectors (RCONDV).
The right eigenvector v(j) of A satisfies
A * v(j) = lambda(j) * v(j)
where lambda(j) is its eigenvalue.
The left eigenvector u(j) of A satisfies
u(j)**H * A = lambda(j) * u(j)**H
where u(j)**H denotes the conjugate transpose of u(j).
The computed eigenvectors are normalized to have Euclidean norm
equal to 1 and largest component real.
Balancing a matrix means permuting the rows and columns to make it
more nearly upper triangular, and applying a diagonal similarity
transformation D * A * D**(-1), where D is a diagonal matrix, to
make its rows and columns closer in norm and the condition numbers
of its eigenvalues and eigenvectors smaller. The computed
reciprocal condition numbers correspond to the balanced matrix.
Permuting rows and columns will not change the condition numbers
(in exact arithmetic) but diagonal scaling will. For further
explanation of balancing, see section 4.10.2 of the LAPACK
Users' Guide.
Arguments
=========
BALANC (input) CHARACTER*1
Indicates how the input matrix should be diagonally scaled
and/or permuted to improve the conditioning of its
eigenvalues.
= 'N': Do not diagonally scale or permute;
= 'P': Perform permutations to make the matrix more nearly
upper triangular. Do not diagonally scale;
= 'S': Diagonally scale the matrix, ie. replace A by
D*A*D**(-1), where D is a diagonal matrix chosen
to make the rows and columns of A more equal in
norm. Do not permute;
= 'B': Both diagonally scale and permute A.
Computed reciprocal condition numbers will be for the matrix
after balancing and/or permuting. Permuting does not change
condition numbers (in exact arithmetic), but balancing does.
JOBVL (input) CHARACTER*1
= 'N': left eigenvectors of A are not computed;
= 'V': left eigenvectors of A are computed.
If SENSE = 'E' or 'B', JOBVL must = 'V'.
JOBVR (input) CHARACTER*1
= 'N': right eigenvectors of A are not computed;
= 'V': right eigenvectors of A are computed.
If SENSE = 'E' or 'B', JOBVR must = 'V'.
SENSE (input) CHARACTER*1
Determines which reciprocal condition numbers are computed.
= 'N': None are computed;
= 'E': Computed for eigenvalues only;
= 'V': Computed for right eigenvectors only;
= 'B': Computed for eigenvalues and right eigenvectors.
If SENSE = 'E' or 'B', both left and right eigenvectors
must also be computed (JOBVL = 'V' and JOBVR = 'V').
N (input) INTEGER
The order of the matrix A. N >= 0.
A (input/output) COMPLEX*16 array, dimension (LDA,N)
On entry, the N-by-N matrix A.
On exit, A has been overwritten. If JOBVL = 'V' or
JOBVR = 'V', A contains the Schur form of the balanced
version of the matrix A.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,N).
W (output) COMPLEX*16 array, dimension (N)
W contains the computed eigenvalues.
VL (output) COMPLEX*16 array, dimension (LDVL,N)
If JOBVL = 'V', the left eigenvectors u(j) are stored one
after another in the columns of VL, in the same order
as their eigenvalues.
If JOBVL = 'N', VL is not referenced.
u(j) = VL(:,j), the j-th column of VL.
LDVL (input) INTEGER
The leading dimension of the array VL. LDVL >= 1; if
JOBVL = 'V', LDVL >= N.
VR (output) COMPLEX*16 array, dimension (LDVR,N)
If JOBVR = 'V', the right eigenvectors v(j) are stored one
after another in the columns of VR, in the same order
as their eigenvalues.
If JOBVR = 'N', VR is not referenced.
v(j) = VR(:,j), the j-th column of VR.
LDVR (input) INTEGER
The leading dimension of the array VR. LDVR >= 1; if
JOBVR = 'V', LDVR >= N.
ILO,IHI (output) INTEGER
ILO and IHI are integer values determined when A was
balanced. The balanced A(i,j) = 0 if I > J and
J = 1,...,ILO-1 or I = IHI+1,...,N.
SCALE (output) DOUBLE PRECISION array, dimension (N)
Details of the permutations and scaling factors applied
when balancing A. If P(j) is the index of the row and column
interchanged with row and column j, and D(j) is the scaling
factor applied to row and column j, then
SCALE(J) = P(J), for J = 1,...,ILO-1
= D(J), for J = ILO,...,IHI
= P(J) for J = IHI+1,...,N.
The order in which the interchanges are made is N to IHI+1,
then 1 to ILO-1.
ABNRM (output) DOUBLE PRECISION
The one-norm of the balanced matrix (the maximum
of the sum of absolute values of elements of any column).
RCONDE (output) DOUBLE PRECISION array, dimension (N)
RCONDE(j) is the reciprocal condition number of the j-th
eigenvalue.
RCONDV (output) DOUBLE PRECISION array, dimension (N)
RCONDV(j) is the reciprocal condition number of the j-th
right eigenvector.
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 SENSE = 'N' or 'E',
LWORK >= max(1,2*N), and if SENSE = 'V' or 'B',
LWORK >= N*N+2*N.
For good performance, LWORK must generally be larger.
RWORK (workspace) DOUBLE PRECISION array, dimension (2*N)
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value.
> 0: if INFO = i, the QR algorithm failed to compute all the
eigenvalues, and no eigenvectors or condition numbers
have been computed; elements 1:ILO-1 and i+1:N of W
contain eigenvalues which have converged.
=====================================================================
Test the input arguments
Parameter adjustments
Function Body */
/* Table of constant values */
static integer c__1 = 1;
static integer c__0 = 0;
static integer c__8 = 8;
static integer c_n1 = -1;
static integer c__4 = 4;
/* System generated locals */
integer a_dim1, a_offset, vl_dim1, vl_offset, vr_dim1, vr_offset, i__1,
i__2, i__3, i__4;
doublereal d__1, d__2;
doublecomplex z__1, z__2;
/* Builtin functions */
double sqrt(doublereal), d_imag(doublecomplex *);
void d_cnjg(doublecomplex *, doublecomplex *);
/* Local variables */
static char side[1];
static integer maxb;
static doublereal anrm;
static integer ierr, itau, iwrk, nout, i, k, icond;
extern logical lsame_(char *, char *);
extern /* Subroutine */ int zscal_(integer *, doublecomplex *,
doublecomplex *, integer *), dlabad_(doublereal *, doublereal *);
extern doublereal dznrm2_(integer *, doublecomplex *, integer *);
static logical scalea;
extern doublereal dlamch_(char *);
static doublereal cscale;
extern /* Subroutine */ int dlascl_(char *, integer *, integer *,
doublereal *, doublereal *, integer *, integer *, doublereal *,
integer *, integer *), zgebak_(char *, char *, integer *,
integer *, integer *, doublereal *, integer *, doublecomplex *,
integer *, integer *), zgebal_(char *, integer *,
doublecomplex *, integer *, integer *, integer *, doublereal *,
integer *);
extern integer idamax_(integer *, doublereal *, integer *);
extern /* Subroutine */ int xerbla_(char *, integer *);
extern integer ilaenv_(integer *, char *, char *, integer *, integer *,
integer *, integer *, ftnlen, ftnlen);
static logical select[1];
extern /* Subroutine */ int zdscal_(integer *, doublereal *,
doublecomplex *, integer *);
static doublereal bignum;
extern doublereal zlange_(char *, integer *, integer *, doublecomplex *,
integer *, doublereal *);
extern /* Subroutine */ int zgehrd_(integer *, integer *, integer *,
doublecomplex *, integer *, doublecomplex *, doublecomplex *,
integer *, integer *), zlascl_(char *, integer *, integer *,
doublereal *, doublereal *, integer *, integer *, doublecomplex *,
integer *, integer *), zlacpy_(char *, integer *,
integer *, doublecomplex *, integer *, doublecomplex *, integer *);
static integer minwrk, maxwrk;
static logical wantvl, wntsnb;
static integer hswork;
static logical wntsne;
static doublereal smlnum;
extern /* Subroutine */ int zhseqr_(char *, char *, integer *, integer *,
integer *, doublecomplex *, integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *, integer *, integer *);
static logical wantvr;
extern /* Subroutine */ int ztrevc_(char *, char *, logical *, integer *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *, integer *, integer *, doublecomplex *,
doublereal *, integer *), ztrsna_(char *, char *,
logical *, integer *, doublecomplex *, integer *, doublecomplex *
, integer *, doublecomplex *, integer *, doublereal *, doublereal
*, integer *, integer *, doublecomplex *, integer *, doublereal *,
integer *), zunghr_(integer *, integer *,
integer *, doublecomplex *, integer *, doublecomplex *,
doublecomplex *, integer *, integer *);
static logical wntsnn, wntsnv;
static char job[1];
static doublereal scl, dum[1], eps;
static doublecomplex tmp;
#define DUM(I) dum[(I)]
#define W(I) w[(I)-1]
#define SCALE(I) scale[(I)-1]
#define RCONDE(I) rconde[(I)-1]
#define RCONDV(I) rcondv[(I)-1]
#define WORK(I) work[(I)-1]
#define RWORK(I) rwork[(I)-1]
#define A(I,J) a[(I)-1 + ((J)-1)* ( *lda)]
#define VL(I,J) vl[(I)-1 + ((J)-1)* ( *ldvl)]
#define VR(I,J) vr[(I)-1 + ((J)-1)* ( *ldvr)]
*info = 0;
wantvl = lsame_(jobvl, "V");
wantvr = lsame_(jobvr, "V");
wntsnn = lsame_(sense, "N");
wntsne = lsame_(sense, "E");
wntsnv = lsame_(sense, "V");
wntsnb = lsame_(sense, "B");
if (! (lsame_(balanc, "N") || lsame_(balanc, "S") ||
lsame_(balanc, "P") || lsame_(balanc, "B"))) {
*info = -1;
} else if (! wantvl && ! lsame_(jobvl, "N")) {
*info = -2;
} else if (! wantvr && ! lsame_(jobvr, "N")) {
*info = -3;
} else if (! (wntsnn || wntsne || wntsnb || wntsnv) || (wntsne || wntsnb)
&& ! (wantvl && wantvr)) {
*info = -4;
} else if (*n < 0) {
*info = -5;
} else if (*lda < max(1,*n)) {
*info = -7;
} else if (*ldvl < 1 || wantvl && *ldvl < *n) {
*info = -10;
} else if (*ldvr < 1 || wantvr && *ldvr < *n) {
*info = -12;
}
/* Compute workspace
(Note: Comments in the code beginning "Workspace:" describe the
minimal amount of workspace needed at that point in the code,
as well as the preferred amount for good performance.
CWorkspace refers to complex workspace, and RWorkspace to real
workspace. NB refers to the optimal block size for the
immediately following subroutine, as returned by ILAENV.
HSWORK refers to the workspace preferred by ZHSEQR, as
calculated below. HSWORK is computed assuming ILO=1 and IHI=N,
the worst case.) */
minwrk = 1;
if (*info == 0 && *lwork >= 1) {
maxwrk = *n + *n * ilaenv_(&c__1, "ZGEHRD", " ", n, &c__1, n, &c__0,
6L, 1L);
if (! wantvl && ! wantvr) {
/* Computing MAX */
i__1 = 1, i__2 = *n << 1;
minwrk = max(i__1,i__2);
if (! (wntsnn || wntsne)) {
/* Computing MAX */
i__1 = minwrk, i__2 = *n * *n + (*n << 1);
minwrk = max(i__1,i__2);
}
/* Computing MAX */
i__1 = ilaenv_(&c__8, "ZHSEQR", "SN", n, &c__1, n, &c_n1, 6L, 2L);
maxb = max(i__1,2);
if (wntsnn) {
/* Computing MIN
Computing MAX */
i__3 = 2, i__4 = ilaenv_(&c__4, "ZHSEQR", "EN", n, &c__1, n, &
c_n1, 6L, 2L);
i__1 = min(maxb,*n), i__2 = max(i__3,i__4);
k = min(i__1,i__2);
} else {
/* Computing MIN
Computing MAX */
i__3 = 2, i__4 = ilaenv_(&c__4, "ZHSEQR", "SN", n, &c__1, n, &
c_n1, 6L, 2L);
i__1 = min(maxb,*n), i__2 = max(i__3,i__4);
k = min(i__1,i__2);
}
/* Computing MAX */
i__1 = k * (k + 2), i__2 = *n << 1;
hswork = max(i__1,i__2);
/* Computing MAX */
i__1 = max(maxwrk,1);
maxwrk = max(i__1,hswork);
if (! (wntsnn || wntsne)) {
/* Computing MAX */
i__1 = maxwrk, i__2 = *n * *n + (*n << 1);
maxwrk = max(i__1,i__2);
}
} else {
/* Computing MAX */
i__1 = 1, i__2 = *n << 1;
minwrk = max(i__1,i__2);
if (! (wntsnn || wntsne)) {
/* Computing MAX */
i__1 = minwrk, i__2 = *n * *n + (*n << 1);
minwrk = max(i__1,i__2);
}
/* Computing MAX */
i__1 = ilaenv_(&c__8, "ZHSEQR", "SN", n, &c__1, n, &c_n1, 6L, 2L);
maxb = max(i__1,2);
/* Computing MIN
Computing MAX */
i__3 = 2, i__4 = ilaenv_(&c__4, "ZHSEQR", "EN", n, &c__1, n, &
c_n1, 6L, 2L);
i__1 = min(maxb,*n), i__2 = max(i__3,i__4);
k = min(i__1,i__2);
/* Computing MAX */
i__1 = k * (k + 2), i__2 = *n << 1;
hswork = max(i__1,i__2);
/* Computing MAX */
i__1 = max(maxwrk,1);
maxwrk = max(i__1,hswork);
/* Computing MAX */
i__1 = maxwrk, i__2 = *n + (*n - 1) * ilaenv_(&c__1, "ZUNGHR",
" ", n, &c__1, n, &c_n1, 6L, 1L);
maxwrk = max(i__1,i__2);
if (! (wntsnn || wntsne)) {
/* Computing MAX */
i__1 = maxwrk, i__2 = *n * *n + (*n << 1);
maxwrk = max(i__1,i__2);
}
/* Computing MAX */
i__1 = maxwrk, i__2 = *n << 1, i__1 = max(i__1,i__2);
maxwrk = max(i__1,1);
}
WORK(1).r = (doublereal) maxwrk, WORK(1).i = 0.;
}
if (*lwork < minwrk) {
*info = -20;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZGEEVX", &i__1);
return 0;
}
/* Quick return if possible */
if (*n == 0) {
return 0;
}
/* Get machine constants */
eps = dlamch_("P");
smlnum = dlamch_("S");
bignum = 1. / smlnum;
dlabad_(&smlnum, &bignum);
smlnum = sqrt(smlnum) / eps;
bignum = 1. / smlnum;
/* Scale A if max element outside range [SMLNUM,BIGNUM] */
icond = 0;
anrm = zlange_("M", n, n, &A(1,1), lda, dum);
scalea = FALSE_;
if (anrm > 0. && anrm < smlnum) {
scalea = TRUE_;
cscale = smlnum;
} else if (anrm > bignum) {
scalea = TRUE_;
cscale = bignum;
}
if (scalea) {
zlascl_("G", &c__0, &c__0, &anrm, &cscale, n, n, &A(1,1), lda, &
ierr);
}
/* Balance the matrix and compute ABNRM */
zgebal_(balanc, n, &A(1,1), lda, ilo, ihi, &SCALE(1), &ierr);
*abnrm = zlange_("1", n, n, &A(1,1), lda, dum);
if (scalea) {
DUM(0) = *abnrm;
dlascl_("G", &c__0, &c__0, &cscale, &anrm, &c__1, &c__1, dum, &c__1, &
ierr);
*abnrm = DUM(0);
}
/* Reduce to upper Hessenberg form
(CWorkspace: need 2*N, prefer N+N*NB)
(RWorkspace: none) */
itau = 1;
iwrk = itau + *n;
i__1 = *lwork - iwrk + 1;
zgehrd_(n, ilo, ihi, &A(1,1), lda, &WORK(itau), &WORK(iwrk), &i__1, &
ierr);
if (wantvl) {
/* Want left eigenvectors
Copy Householder vectors to VL */
*(unsigned char *)side = 'L';
zlacpy_("L", n, n, &A(1,1), lda, &VL(1,1), ldvl);
/* Generate unitary matrix in VL
(CWorkspace: need 2*N-1, prefer N+(N-1)*NB)
(RWorkspace: none) */
i__1 = *lwork - iwrk + 1;
zunghr_(n, ilo, ihi, &VL(1,1), ldvl, &WORK(itau), &WORK(iwrk), &
i__1, &ierr);
/* Perform QR iteration, accumulating Schur vectors in VL
(CWorkspace: need 1, prefer HSWORK (see comments) )
(RWorkspace: none) */
iwrk = itau;
i__1 = *lwork - iwrk + 1;
zhseqr_("S", "V", n, ilo, ihi, &A(1,1), lda, &W(1), &VL(1,1), ldvl, &WORK(iwrk), &i__1, info);
if (wantvr) {
/* Want left and right eigenvectors
Copy Schur vectors to VR */
*(unsigned char *)side = 'B';
zlacpy_("F", n, n, &VL(1,1), ldvl, &VR(1,1), ldvr)
;
}
} else if (wantvr) {
/* Want right eigenvectors
Copy Householder vectors to VR */
*(unsigned char *)side = 'R';
zlacpy_("L", n, n, &A(1,1), lda, &VR(1,1), ldvr);
/* Generate unitary matrix in VR
(CWorkspace: need 2*N-1, prefer N+(N-1)*NB)
(RWorkspace: none) */
i__1 = *lwork - iwrk + 1;
zunghr_(n, ilo, ihi, &VR(1,1), ldvr, &WORK(itau), &WORK(iwrk), &
i__1, &ierr);
/* Perform QR iteration, accumulating Schur vectors in VR
(CWorkspace: need 1, prefer HSWORK (see comments) )
(RWorkspace: none) */
iwrk = itau;
i__1 = *lwork - iwrk + 1;
zhseqr_("S", "V", n, ilo, ihi, &A(1,1), lda, &W(1), &VR(1,1), ldvr, &WORK(iwrk), &i__1, info);
} else {
/* Compute eigenvalues only
If condition numbers desired, compute Schur form */
if (wntsnn) {
*(unsigned char *)job = 'E';
} else {
*(unsigned char *)job = 'S';
}
/* (CWorkspace: need 1, prefer HSWORK (see comments) )
(RWorkspace: none) */
iwrk = itau;
i__1 = *lwork - iwrk + 1;
zhseqr_(job, "N", n, ilo, ihi, &A(1,1), lda, &W(1), &VR(1,1), ldvr, &WORK(iwrk), &i__1, info);
}
/* If INFO > 0 from ZHSEQR, then quit */
if (*info > 0) {
goto L50;
}
if (wantvl || wantvr) {
/* Compute left and/or right eigenvectors
(CWorkspace: need 2*N)
(RWorkspace: need N) */
ztrevc_(side, "B", select, n, &A(1,1), lda, &VL(1,1), ldvl,
&VR(1,1), ldvr, n, &nout, &WORK(iwrk), &RWORK(1), &
ierr);
}
/* Compute condition numbers if desired
(CWorkspace: need N*N+2*N unless SENSE = 'E')
(RWorkspace: need 2*N unless SENSE = 'E') */
if (! wntsnn) {
ztrsna_(sense, "A", select, n, &A(1,1), lda, &VL(1,1),
ldvl, &VR(1,1), ldvr, &RCONDE(1), &RCONDV(1), n, &nout,
&WORK(iwrk), n, &RWORK(1), &icond);
}
if (wantvl) {
/* Undo balancing of left eigenvectors */
zgebak_(balanc, "L", n, ilo, ihi, &SCALE(1), n, &VL(1,1), ldvl,
&ierr);
/* Normalize left eigenvectors and make largest component real
*/
i__1 = *n;
for (i = 1; i <= *n; ++i) {
scl = 1. / dznrm2_(n, &VL(1,i), &c__1);
zdscal_(n, &scl, &VL(1,i), &c__1);
i__2 = *n;
for (k = 1; k <= *n; ++k) {
i__3 = k + i * vl_dim1;
/* Computing 2nd power */
d__1 = VL(k,i).r;
/* Computing 2nd power */
d__2 = d_imag(&VL(k,i));
RWORK(k) = d__1 * d__1 + d__2 * d__2;
/* L10: */
}
k = idamax_(n, &RWORK(1), &c__1);
d_cnjg(&z__2, &VL(k,i));
d__1 = sqrt(RWORK(k));
z__1.r = z__2.r / d__1, z__1.i = z__2.i / d__1;
tmp.r = z__1.r, tmp.i = z__1.i;
zscal_(n, &tmp, &VL(1,i), &c__1);
i__2 = k + i * vl_dim1;
i__3 = k + i * vl_dim1;
d__1 = VL(k,i).r;
z__1.r = d__1, z__1.i = 0.;
VL(k,i).r = z__1.r, VL(k,i).i = z__1.i;
/* L20: */
}
}
if (wantvr) {
/* Undo balancing of right eigenvectors */
zgebak_(balanc, "R", n, ilo, ihi, &SCALE(1), n, &VR(1,1), ldvr,
&ierr);
/* Normalize right eigenvectors and make largest component real
*/
i__1 = *n;
for (i = 1; i <= *n; ++i) {
scl = 1. / dznrm2_(n, &VR(1,i), &c__1);
zdscal_(n, &scl, &VR(1,i), &c__1);
i__2 = *n;
for (k = 1; k <= *n; ++k) {
i__3 = k + i * vr_dim1;
/* Computing 2nd power */
d__1 = VR(k,i).r;
/* Computing 2nd power */
d__2 = d_imag(&VR(k,i));
RWORK(k) = d__1 * d__1 + d__2 * d__2;
/* L30: */
}
k = idamax_(n, &RWORK(1), &c__1);
d_cnjg(&z__2, &VR(k,i));
d__1 = sqrt(RWORK(k));
z__1.r = z__2.r / d__1, z__1.i = z__2.i / d__1;
tmp.r = z__1.r, tmp.i = z__1.i;
zscal_(n, &tmp, &VR(1,i), &c__1);
i__2 = k + i * vr_dim1;
i__3 = k + i * vr_dim1;
d__1 = VR(k,i).r;
z__1.r = d__1, z__1.i = 0.;
VR(k,i).r = z__1.r, VR(k,i).i = z__1.i;
/* L40: */
}
}
/* Undo scaling if necessary */
L50:
if (scalea) {
i__1 = *n - *info;
/* Computing MAX */
i__3 = *n - *info;
i__2 = max(i__3,1);
zlascl_("G", &c__0, &c__0, &cscale, &anrm, &i__1, &c__1, &W(*info + 1)
, &i__2, &ierr);
if (*info == 0) {
if ((wntsnv || wntsnb) && icond == 0) {
dlascl_("G", &c__0, &c__0, &cscale, &anrm, n, &c__1, &RCONDV(
1), n, &ierr);
}
} else {
i__1 = *ilo - 1;
zlascl_("G", &c__0, &c__0, &cscale, &anrm, &i__1, &c__1, &W(1), n,
&ierr);
}
}
WORK(1).r = (doublereal) maxwrk, WORK(1).i = 0.;
return 0;
/* End of ZGEEVX */
} /* zgeevx_ */
