zgeev - compute for an N-by-N complex nonsymmetric matrix A, the eigenvalues and, optionally, the left and/or right eigenvectors
SUBROUTINE ZGEEV( JOBVL, JOBVR, N, A, LDA, W, VL, LDVL, VR, LDVR, * WORK, LDWORK, WORK2, INFO) CHARACTER * 1 JOBVL, JOBVR DOUBLE COMPLEX A(LDA,*), W(*), VL(LDVL,*), VR(LDVR,*), WORK(*) INTEGER N, LDA, LDVL, LDVR, LDWORK, INFO DOUBLE PRECISION WORK2(*)
SUBROUTINE ZGEEV_64( JOBVL, JOBVR, N, A, LDA, W, VL, LDVL, VR, LDVR, * WORK, LDWORK, WORK2, INFO) CHARACTER * 1 JOBVL, JOBVR DOUBLE COMPLEX A(LDA,*), W(*), VL(LDVL,*), VR(LDVR,*), WORK(*) INTEGER*8 N, LDA, LDVL, LDVR, LDWORK, INFO DOUBLE PRECISION WORK2(*)
SUBROUTINE GEEV( JOBVL, JOBVR, [N], A, [LDA], W, VL, [LDVL], VR, * [LDVR], [WORK], [LDWORK], [WORK2], [INFO]) CHARACTER(LEN=1) :: JOBVL, JOBVR COMPLEX(8), DIMENSION(:) :: W, WORK COMPLEX(8), DIMENSION(:,:) :: A, VL, VR INTEGER :: N, LDA, LDVL, LDVR, LDWORK, INFO REAL(8), DIMENSION(:) :: WORK2
SUBROUTINE GEEV_64( JOBVL, JOBVR, [N], A, [LDA], W, VL, [LDVL], VR, * [LDVR], [WORK], [LDWORK], [WORK2], [INFO]) CHARACTER(LEN=1) :: JOBVL, JOBVR COMPLEX(8), DIMENSION(:) :: W, WORK COMPLEX(8), DIMENSION(:,:) :: A, VL, VR INTEGER(8) :: N, LDA, LDVL, LDVR, LDWORK, INFO REAL(8), DIMENSION(:) :: WORK2
#include <sunperf.h>
void zgeev(char jobvl, char jobvr, int n, doublecomplex *a, int lda, doublecomplex *w, doublecomplex *vl, int ldvl, doublecomplex *vr, int ldvr, int *info);
void zgeev_64(char jobvl, char jobvr, long n, doublecomplex *a, long lda, doublecomplex *w, doublecomplex *vl, long ldvl, doublecomplex *vr, long ldvr, long *info);
zgeev computes for an N-by-N complex nonsymmetric matrix A, the eigenvalues and, optionally, the left and/or right eigenvectors.
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.
= 'N': left eigenvectors of A are not computed;
= 'V': left eigenvectors of are computed.
= 'N': right eigenvectors of A are not computed;
= 'V': right eigenvectors of A are computed.
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.
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.
WORK(1)
returns the optimal LDWORK.
If LDWORK = -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 LDWORK is issued by XERBLA.
dimension(2*N)
= 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 have been computed; elements and i+1:N of W contain eigenvalues which have converged.