dsytri (3p)

Name

dsytri - compute the inverse of a real symmetric indefinite matrix A using the factorization A = U*D*U**T or A = L*D*L**T computed by DSYTRF

Synopsis

SUBROUTINE DSYTRI(UPLO, N, A, LDA, IPIVOT, WORK, INFO)

CHARACTER*1 UPLO
INTEGER N, LDA, INFO
INTEGER IPIVOT(*)
DOUBLE PRECISION A(LDA,*), WORK(*)

SUBROUTINE DSYTRI_64(UPLO, N, A, LDA, IPIVOT, WORK, INFO)

CHARACTER*1 UPLO
INTEGER*8 N, LDA, INFO
INTEGER*8 IPIVOT(*)
DOUBLE PRECISION A(LDA,*), WORK(*)




F95 INTERFACE
SUBROUTINE SYTRI(UPLO, N, A, LDA, IPIVOT, WORK, INFO)

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

SUBROUTINE SYTRI_64(UPLO, N, A, LDA, IPIVOT, WORK, INFO)

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




C INTERFACE
#include <sunperf.h>

void  dsytri(char  uplo,  int  n,  double *a, int lda, int *ipivot, int
*info);

void dsytri_64(char uplo, long n, double *a, long  lda,  long  *ipivot,
long *info);

Description

Oracle Solaris Studio Performance Library                           dsytri(3P)



NAME
       dsytri  -  compute  the inverse of a real symmetric indefinite matrix A
       using the factorization A = U*D*U**T or A = L*D*L**T computed by DSYTRF


SYNOPSIS
       SUBROUTINE DSYTRI(UPLO, N, A, LDA, IPIVOT, WORK, INFO)

       CHARACTER*1 UPLO
       INTEGER N, LDA, INFO
       INTEGER IPIVOT(*)
       DOUBLE PRECISION A(LDA,*), WORK(*)

       SUBROUTINE DSYTRI_64(UPLO, N, A, LDA, IPIVOT, WORK, INFO)

       CHARACTER*1 UPLO
       INTEGER*8 N, LDA, INFO
       INTEGER*8 IPIVOT(*)
       DOUBLE PRECISION A(LDA,*), WORK(*)




   F95 INTERFACE
       SUBROUTINE SYTRI(UPLO, N, A, LDA, IPIVOT, WORK, INFO)

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

       SUBROUTINE SYTRI_64(UPLO, N, A, LDA, IPIVOT, WORK, INFO)

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




   C INTERFACE
       #include <sunperf.h>

       void  dsytri(char  uplo,  int  n,  double *a, int lda, int *ipivot, int
                 *info);

       void dsytri_64(char uplo, long n, double *a, long  lda,  long  *ipivot,
                 long *info);



PURPOSE
       dsytri  computes  the  inverse  of a real symmetric indefinite matrix A
       using the factorization A =  U*D*U**T  or  A  =  L*D*L**T  computed  by
       DSYTRF.


ARGUMENTS
       UPLO (input)
                 Specifies whether the details of the factorization are stored
                 as an upper or lower triangular matrix.  = 'U':  Upper trian-
                 gular, form is A = U*D*U**T;
                 = 'L':  Lower triangular, form is A = L*D*L**T.


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


       A (input/output)
                 On  entry,  the  block  diagonal matrix D and the multipliers
                 used to obtain the factor U or L as computed by DSYTRF.

                 On exit, if INFO = 0, the (symmetric) inverse of the original
                 matrix.   If  UPLO  =  'U',  the upper triangular part of the
                 inverse is formed and the part of A below the diagonal is not
                 referenced;  if  UPLO  = 'L' the lower triangular part of the
                 inverse is formed and the part of A above the diagonal is not
                 referenced.


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


       IPIVOT (input)
                 Details  of  the interchanges and the block structure of D as
                 determined by DSYTRF.


       WORK (workspace)
                 dimension(N)

       INFO (output)
                 = 0: successful exit
                 < 0: if INFO = -i, the i-th argument had an illegal value
                 > 0: if INFO = i, D(i,i) = 0; the matrix is singular and  its
                 inverse could not be computed.




                                  7 Nov 2015                        dsytri(3P)