ssyev (3p)

Name

ssyev - compute all eigenvalues and, optionally, eigenvectors of a real symmetric matrix A

Synopsis

SUBROUTINE SSYEV(JOBZ, UPLO, N, A, LDA, W, WORK, LDWORK, INFO)

CHARACTER*1 JOBZ, UPLO
INTEGER N, LDA, LDWORK, INFO
REAL A(LDA,*), W(*), WORK(*)

SUBROUTINE SSYEV_64(JOBZ, UPLO, N, A, LDA, W, WORK, LDWORK, INFO)

CHARACTER*1 JOBZ, UPLO
INTEGER*8 N, LDA, LDWORK, INFO
REAL A(LDA,*), W(*), WORK(*)




F95 INTERFACE
SUBROUTINE SYEV(JOBZ, UPLO, N, A, LDA, W, WORK, LDWORK, INFO)

CHARACTER(LEN=1) :: JOBZ, UPLO
INTEGER :: N, LDA, LDWORK, INFO
REAL, DIMENSION(:) :: W, WORK
REAL, DIMENSION(:,:) :: A

SUBROUTINE SYEV_64(JOBZ, UPLO, N, A, LDA, W, WORK, LDWORK,
INFO)

CHARACTER(LEN=1) :: JOBZ, UPLO
INTEGER(8) :: N, LDA, LDWORK, INFO
REAL, DIMENSION(:) :: W, WORK
REAL, DIMENSION(:,:) :: A




C INTERFACE
#include <sunperf.h>

void ssyev(char jobz, char uplo, int n, float *a, int  lda,  float  *w,
int *info);

void  ssyev_64(char  jobz, char uplo, long n, float *a, long lda, float
*w, long *info);

Description

Oracle Solaris Studio Performance Library                            ssyev(3P)



NAME
       ssyev - compute all eigenvalues and, optionally, eigenvectors of a real
       symmetric matrix A


SYNOPSIS
       SUBROUTINE SSYEV(JOBZ, UPLO, N, A, LDA, W, WORK, LDWORK, INFO)

       CHARACTER*1 JOBZ, UPLO
       INTEGER N, LDA, LDWORK, INFO
       REAL A(LDA,*), W(*), WORK(*)

       SUBROUTINE SSYEV_64(JOBZ, UPLO, N, A, LDA, W, WORK, LDWORK, INFO)

       CHARACTER*1 JOBZ, UPLO
       INTEGER*8 N, LDA, LDWORK, INFO
       REAL A(LDA,*), W(*), WORK(*)




   F95 INTERFACE
       SUBROUTINE SYEV(JOBZ, UPLO, N, A, LDA, W, WORK, LDWORK, INFO)

       CHARACTER(LEN=1) :: JOBZ, UPLO
       INTEGER :: N, LDA, LDWORK, INFO
       REAL, DIMENSION(:) :: W, WORK
       REAL, DIMENSION(:,:) :: A

       SUBROUTINE SYEV_64(JOBZ, UPLO, N, A, LDA, W, WORK, LDWORK,
              INFO)

       CHARACTER(LEN=1) :: JOBZ, UPLO
       INTEGER(8) :: N, LDA, LDWORK, INFO
       REAL, DIMENSION(:) :: W, WORK
       REAL, DIMENSION(:,:) :: A




   C INTERFACE
       #include <sunperf.h>

       void ssyev(char jobz, char uplo, int n, float *a, int  lda,  float  *w,
                 int *info);

       void  ssyev_64(char  jobz, char uplo, long n, float *a, long lda, float
                 *w, long *info);



PURPOSE
       ssyev computes all eigenvalues and, optionally, eigenvectors of a  real
       symmetric matrix A.


ARGUMENTS
       JOBZ (input)
                 = 'N':  Compute eigenvalues only;
                 = 'V':  Compute eigenvalues and eigenvectors.


       UPLO (input)
                 = 'U':  Upper triangle of A is stored;
                 = 'L':  Lower triangle of A is stored.


       N (input) The order of the matrix A.  N >= 0.


       A (input/output)
                 On entry, the symmetric matrix A.  If UPLO = 'U', the leading
                 N-by-N upper triangular part of A contains the upper triangu-
                 lar  part of the matrix A.  If UPLO = 'L', the leading N-by-N
                 lower triangular part of A contains the lower triangular part
                 of the matrix A.  On exit, if JOBZ = 'V', then if INFO = 0, A
                 contains the orthonormal eigenvectors of the  matrix  A.   If
                 JOBZ  = 'N', then on exit the lower triangle (if UPLO='L') or
                 the upper triangle (if UPLO='U') of A, including  the  diago-
                 nal, is destroyed.


       LDA (input)
                 The leading dimension of the array A.  LDA >= max(1,N).


       W (output)
                 If INFO = 0, the eigenvalues in ascending order.


       WORK (workspace)
                 On exit, if INFO = 0, WORK(1) returns the optimal LDWORK.


       LDWORK (input)
                 The  length  of the array WORK.  LDWORK >= max(1,3*N-1).  For
                 optimal efficiency, LDWORK  >=  (NB+2)*N,  where  NB  is  the
                 blocksize for SSYTRD returned by ILAENV.

                 If  LDWORK  = -1, then a workspace query is assumed; the rou-
                 tine 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.


       INFO (output)
                 = 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.




                                  7 Nov 2015                         ssyev(3P)