ctgevc
ctgevc - compute some or all of the right and/or left generalized eigenvectors of a pair of complex upper triangular matrices (A,B)
SUBROUTINE CTGEVC( SIDE, HOWMNY, SELECT, N, A, LDA, B, LDB, VL,
* LDVL, VR, LDVR, MM, M, WORK, RWORK, INFO)
CHARACTER * 1 SIDE, HOWMNY
COMPLEX A(LDA,*), B(LDB,*), VL(LDVL,*), VR(LDVR,*), WORK(*)
INTEGER N, LDA, LDB, LDVL, LDVR, MM, M, INFO
LOGICAL SELECT(*)
REAL RWORK(*)
SUBROUTINE CTGEVC_64( SIDE, HOWMNY, SELECT, N, A, LDA, B, LDB, VL,
* LDVL, VR, LDVR, MM, M, WORK, RWORK, INFO)
CHARACTER * 1 SIDE, HOWMNY
COMPLEX A(LDA,*), B(LDB,*), VL(LDVL,*), VR(LDVR,*), WORK(*)
INTEGER*8 N, LDA, LDB, LDVL, LDVR, MM, M, INFO
LOGICAL*8 SELECT(*)
REAL RWORK(*)
SUBROUTINE TGEVC( SIDE, HOWMNY, SELECT, [N], A, [LDA], B, [LDB], VL,
* [LDVL], VR, [LDVR], MM, M, [WORK], [RWORK], [INFO])
CHARACTER(LEN=1) :: SIDE, HOWMNY
COMPLEX, DIMENSION(:) :: WORK
COMPLEX, DIMENSION(:,:) :: A, B, VL, VR
INTEGER :: N, LDA, LDB, LDVL, LDVR, MM, M, INFO
LOGICAL, DIMENSION(:) :: SELECT
REAL, DIMENSION(:) :: RWORK
SUBROUTINE TGEVC_64( SIDE, HOWMNY, SELECT, [N], A, [LDA], B, [LDB],
* VL, [LDVL], VR, [LDVR], MM, M, [WORK], [RWORK], [INFO])
CHARACTER(LEN=1) :: SIDE, HOWMNY
COMPLEX, DIMENSION(:) :: WORK
COMPLEX, DIMENSION(:,:) :: A, B, VL, VR
INTEGER(8) :: N, LDA, LDB, LDVL, LDVR, MM, M, INFO
LOGICAL(8), DIMENSION(:) :: SELECT
REAL, DIMENSION(:) :: RWORK
#include <sunperf.h>
void ctgevc(char side, char howmny, logical *select, int n, complex *a, int lda, complex *b, int ldb, complex *vl, int ldvl, complex *vr, int ldvr, int mm, int *m, int *info);
void ctgevc_64(char side, char howmny, logical *select, long n, complex *a, long lda, complex *b, long ldb, complex *vl, long ldvl, complex *vr, long ldvr, long mm, long *m, long *info);
ctgevc computes some or all of the right and/or left generalized
eigenvectors of a pair of complex upper triangular matrices (A,B).
The right generalized eigenvector x and the left generalized
eigenvector y of (A,B) corresponding to a generalized eigenvalue
w are defined by:
(A - wB) * x = 0 and y**H * (A - wB) = 0
where y**H denotes the conjugate tranpose of y.
If an eigenvalue w is determined by zero diagonal elements of both A
and B, a unit vector is returned as the corresponding eigenvector.
If all eigenvectors are requested, the routine may either return
the matrices X and/or Y of right or left eigenvectors of (A,B), or
the products Z*X and/or Q*Y, where Z and Q are input unitary
matrices. If (A,B) was obtained from the generalized Schur
factorization of an original pair of matrices
(A0,B0) = (Q*A*Z**H,Q*B*Z**H),
then Z*X and Q*Y are the matrices of right or left eigenvectors of
A.
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* SIDE (input)
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* HOWMNY (input)
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* SELECT (input)
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If HOWMNY='S', SELECT specifies the eigenvectors to be
computed.
If HOWMNY='A' or 'B', SELECT is not referenced.
To select the eigenvector corresponding to the j-th
eigenvalue, SELECT(j) must be set to .TRUE..
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* N (input)
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The order of the matrices A and B. N >= 0.
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* A (input)
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The upper triangular matrix A.
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* LDA (input)
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The leading dimension of array A. LDA >= max(1,N).
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* B (input)
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The upper triangular matrix B. B must have real diagonal
elements.
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* LDB (input)
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The leading dimension of array B. LDB >= max(1,N).
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* VL (input/output)
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On entry, if SIDE = 'L' or 'B' and HOWMNY = 'B', VL must
contain an N-by-N matrix Q (usually the unitary matrix Q
of left Schur vectors returned by CHGEQZ).
On exit, if SIDE = 'L' or 'B', VL contains:
if HOWMNY = 'A', the matrix Y of left eigenvectors of (A,B);
if HOWMNY = 'B', the matrix Q*Y;
if HOWMNY = 'S', the left eigenvectors of (A,B) specified by
SELECT, stored consecutively in the columns of
VL, in the same order as their eigenvalues.
If SIDE = 'R', VL is not referenced.
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* LDVL (input)
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The leading dimension of array VL.
LDVL >= max(1,N) if SIDE = 'L' or 'B'; LDVL >= 1 otherwise.
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* VR (input/output)
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On entry, if SIDE = 'R' or 'B' and HOWMNY = 'B', VR must
contain an N-by-N matrix Q (usually the unitary matrix Z
of right Schur vectors returned by CHGEQZ).
On exit, if SIDE = 'R' or 'B', VR contains:
if HOWMNY = 'A', the matrix X of right eigenvectors of (A,B);
if HOWMNY = 'B', the matrix Z*X;
if HOWMNY = 'S', the right eigenvectors of (A,B) specified by
SELECT, stored consecutively in the columns of
VR, in the same order as their eigenvalues.
If SIDE = 'L', VR is not referenced.
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* LDVR (input)
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The leading dimension of the array VR.
LDVR >= max(1,N) if SIDE = 'R' or 'B'; LDVR >= 1 otherwise.
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* MM (input)
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The number of columns in the arrays VL and/or VR. MM >= M.
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* M (output)
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The number of columns in the arrays VL and/or VR actually
used to store the eigenvectors. If HOWMNY = 'A' or 'B', M
is set to N. Each selected eigenvector occupies one column.
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* WORK (workspace)
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dimension(2*N)
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* RWORK (workspace)
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dimension(2*N)
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* INFO (output)
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