ssbev (3p)

Name

ssbev - compute all the eigenvalues and, optionally, eigenvectors of a real symmetric band matrix A

Synopsis

SUBROUTINE SSBEV(JOBZ, UPLO, N, KD, A, LDA, W, Z, LDZ, WORK, INFO)

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

SUBROUTINE SSBEV_64(JOBZ, UPLO, N, KD, A, LDA, W, Z, LDZ, WORK,
INFO)

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




F95 INTERFACE
SUBROUTINE SBEV(JOBZ, UPLO, N, KD, A, LDA, W, Z, LDZ, WORK,
INFO)

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

SUBROUTINE SBEV_64(JOBZ, UPLO, N, KD, A, LDA, W, Z, LDZ,
WORK, INFO)

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




C INTERFACE
#include <sunperf.h>

void ssbev(char jobz, char uplo, int n, int  kd,  float  *a,  int  lda,
float *w, float *z, int ldz, int *info);

void  ssbev_64(char  jobz,  char  uplo, long n, long kd, float *a, long
lda, float *w, float *z, long ldz, long *info);

Description

Oracle Solaris Studio Performance Library                            ssbev(3P)



NAME
       ssbev  - compute all the eigenvalues and, optionally, eigenvectors of a
       real symmetric band matrix A


SYNOPSIS
       SUBROUTINE SSBEV(JOBZ, UPLO, N, KD, A, LDA, W, Z, LDZ, WORK, INFO)

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

       SUBROUTINE SSBEV_64(JOBZ, UPLO, N, KD, A, LDA, W, Z, LDZ, WORK,
             INFO)

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




   F95 INTERFACE
       SUBROUTINE SBEV(JOBZ, UPLO, N, KD, A, LDA, W, Z, LDZ, WORK,
              INFO)

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

       SUBROUTINE SBEV_64(JOBZ, UPLO, N, KD, A, LDA, W, Z, LDZ,
              WORK, INFO)

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




   C INTERFACE
       #include <sunperf.h>

       void ssbev(char jobz, char uplo, int n, int  kd,  float  *a,  int  lda,
                 float *w, float *z, int ldz, int *info);

       void  ssbev_64(char  jobz,  char  uplo, long n, long kd, float *a, long
                 lda, float *w, float *z, long ldz, long *info);



PURPOSE
       ssbev computes all the eigenvalues and, optionally, eigenvectors  of  a
       real symmetric band 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.


       KD (input)
                 The  number  of superdiagonals of the matrix A if UPLO = 'U',
                 or the number of subdiagonals if UPLO = 'L'.  KD >= 0.


       A (input/output)
                 On entry, the upper or lower triangle of the  symmetric  band
                 matrix A, stored in the first KD+1 rows of the array.  The j-
                 th column of A is stored in the j-th column of the array A as
                 follows:  if  UPLO = 'U', A(kd+1+i-j,j) = A(i,j) for max(1,j-
                 kd)<=i<=j;  if  UPLO  =  'L',  A(1+i-j,j)     =  A(i,j)   for
                 j<=i<=min(n,j+kd).

                 On  exit,  A  is  overwritten  by values generated during the
                 reduction to tridiagonal form.  If  UPLO  =  'U',  the  first
                 superdiagonal  and  the  diagonal of the tridiagonal matrix T
                 are returned in rows KD and KD+1 of A, and if UPLO = 'L', the
                 diagonal and first subdiagonal of T are returned in the first
                 two rows of A.


       LDA (input)
                 The leading dimension of the array A.  LDA >= KD + 1.


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


       Z (output)
                 If JOBZ = 'V', then if INFO = 0, Z contains  the  orthonormal
                 eigenvectors of the matrix A, with the i-th column of Z hold-
                 ing 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)
                 dimension(MAX(1,3*N-2))

       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                         ssbev(3P)