dstev
dstev - compute all eigenvalues and, optionally, eigenvectors of a real symmetric tridiagonal matrix A
SUBROUTINE DSTEV( JOBZ, N, DIAG, OFFD, Z, LDZ, WORK, INFO)
CHARACTER * 1 JOBZ
INTEGER N, LDZ, INFO
DOUBLE PRECISION DIAG(*), OFFD(*), Z(LDZ,*), WORK(*)
SUBROUTINE DSTEV_64( JOBZ, N, DIAG, OFFD, Z, LDZ, WORK, INFO)
CHARACTER * 1 JOBZ
INTEGER*8 N, LDZ, INFO
DOUBLE PRECISION DIAG(*), OFFD(*), Z(LDZ,*), WORK(*)
SUBROUTINE STEV( JOBZ, N, DIAG, OFFD, Z, [LDZ], [WORK], [INFO])
CHARACTER(LEN=1) :: JOBZ
INTEGER :: N, LDZ, INFO
REAL(8), DIMENSION(:) :: DIAG, OFFD, WORK
REAL(8), DIMENSION(:,:) :: Z
SUBROUTINE STEV_64( JOBZ, N, DIAG, OFFD, Z, [LDZ], [WORK], [INFO])
CHARACTER(LEN=1) :: JOBZ
INTEGER(8) :: N, LDZ, INFO
REAL(8), DIMENSION(:) :: DIAG, OFFD, WORK
REAL(8), DIMENSION(:,:) :: Z
#include <sunperf.h>
void dstev(char jobz, int n, double *diag, double *offd, double *z, int ldz, int *info);
void dstev_64(char jobz, long n, double *diag, double *offd, double *z, long ldz, long *info);
dstev computes all eigenvalues and, optionally, eigenvectors of a
real symmetric tridiagonal matrix A.
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* JOBZ (input)
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* N (input)
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The order of the matrix. N >= 0.
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* DIAG (input/output)
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On entry, the n diagonal elements of the tridiagonal matrix
A.
On exit, if INFO = 0, the eigenvalues in ascending order.
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* OFFD (input/output)
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On entry, the (n-1) subdiagonal elements of the tridiagonal
matrix A, stored in elements 1 to N-1 of OFFD; OFFD(N) need not
be set, but is used by the routine.
On exit, the contents of OFFD are destroyed.
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* Z (input)
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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 DIAG(i).
If JOBZ = 'N', then Z is not referenced.
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* LDZ (input)
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The leading dimension of the array Z. LDZ >= 1, and if
JOBZ = 'V', LDZ >= max(1,N).
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* WORK (workspace)
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If JOBZ = 'N', WORK is not referenced.
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* INFO (output)
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