sspev (3p)

Name

sspev - compute all the eigenvalues and, optionally, eigenvectors of a real symmetric matrix A in packed storage

Synopsis

SUBROUTINE SSPEV(JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO)

CHARACTER*1 JOBZ, UPLO
INTEGER N, LDZ, INFO
REAL AP(*), W(*), Z(LDZ,*), WORK(*)

SUBROUTINE SSPEV_64(JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO)

CHARACTER*1 JOBZ, UPLO
INTEGER*8 N, LDZ, INFO
REAL AP(*), W(*), Z(LDZ,*), WORK(*)




F95 INTERFACE
SUBROUTINE SPEV(JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO)

CHARACTER(LEN=1) :: JOBZ, UPLO
INTEGER :: N, LDZ, INFO
REAL, DIMENSION(:) :: AP, W, WORK
REAL, DIMENSION(:,:) :: Z

SUBROUTINE SPEV_64(JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO)

CHARACTER(LEN=1) :: JOBZ, UPLO
INTEGER(8) :: N, LDZ, INFO
REAL, DIMENSION(:) :: AP, W, WORK
REAL, DIMENSION(:,:) :: Z




C INTERFACE
#include <sunperf.h>

void sspev(char jobz, char uplo, int n, float *ap, float *w, float  *z,
int ldz, int *info);

void  sspev_64(char jobz, char uplo, long n, float *ap, float *w, float
*z, long ldz, long *info);

Description

Oracle Solaris Studio Performance Library                            sspev(3P)



NAME
       sspev  - compute all the eigenvalues and, optionally, eigenvectors of a
       real symmetric matrix A in packed storage


SYNOPSIS
       SUBROUTINE SSPEV(JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO)

       CHARACTER*1 JOBZ, UPLO
       INTEGER N, LDZ, INFO
       REAL AP(*), W(*), Z(LDZ,*), WORK(*)

       SUBROUTINE SSPEV_64(JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO)

       CHARACTER*1 JOBZ, UPLO
       INTEGER*8 N, LDZ, INFO
       REAL AP(*), W(*), Z(LDZ,*), WORK(*)




   F95 INTERFACE
       SUBROUTINE SPEV(JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO)

       CHARACTER(LEN=1) :: JOBZ, UPLO
       INTEGER :: N, LDZ, INFO
       REAL, DIMENSION(:) :: AP, W, WORK
       REAL, DIMENSION(:,:) :: Z

       SUBROUTINE SPEV_64(JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO)

       CHARACTER(LEN=1) :: JOBZ, UPLO
       INTEGER(8) :: N, LDZ, INFO
       REAL, DIMENSION(:) :: AP, W, WORK
       REAL, DIMENSION(:,:) :: Z




   C INTERFACE
       #include <sunperf.h>

       void sspev(char jobz, char uplo, int n, float *ap, float *w, float  *z,
                 int ldz, int *info);

       void  sspev_64(char jobz, char uplo, long n, float *ap, float *w, float
                 *z, long ldz, long *info);



PURPOSE
       sspev computes all the eigenvalues and, optionally, eigenvectors  of  a
       real symmetric matrix A in packed storage.


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.


       AP (input/output)
                 Real  array,  dimension  (N*(N+1)/2)  On  entry, the upper or
                 lower triangle of the symmetric matrix A,  packed  columnwise
                 in  a  linear  array.   The j-th column of A is stored in the
                 array AP as follows: if UPLO  =  'U',  AP(i  +  (j-1)*j/2)  =
                 A(i,j)  for 1<=i<=j; if UPLO = 'L', AP(i + (j-1)*(2*n-j)/2) =
                 A(i,j) for j<=i<=n.

                 On exit, AP is overwritten by  values  generated  during  the
                 reduction  to  tridiagonal form.  If UPLO = 'U', the diagonal
                 and first superdiagonal of the tridiagonal matrix T overwrite
                 the corresponding elements of A, and if UPLO = 'L', the diag-
                 onal and first subdiagonal of T overwrite  the  corresponding
                 elements of A.


       W (output)
                 Real  array,  dimension  (N)  If INFO = 0, the eigenvalues in
                 ascending order.


       Z (output)
                 Real array, dimension (LDZ, N) 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 W(i).  If JOBZ = 'N', then Z is not referenced.


       LDZ (input)
                 The  leading dimension of the array Z.  LDZ >= 1, and if JOBZ
                 = 'V', LDZ >= max(1,N).


       WORK (workspace)
                 Real array, dimension(3*N)

       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                         sspev(3P)