ssptri (3p)

Name

ssptri - compute the inverse of a real symmetric indefinite matrix A in packed storage using the factorization A = U*D*U**T or A = L*D*L**T computed by SSPTRF

Synopsis

SUBROUTINE SSPTRI(UPLO, N, AP, IPIVOT, WORK, INFO)

CHARACTER*1 UPLO
INTEGER N, INFO
INTEGER IPIVOT(*)
REAL AP(*), WORK(*)

SUBROUTINE SSPTRI_64(UPLO, N, AP, IPIVOT, WORK, INFO)

CHARACTER*1 UPLO
INTEGER*8 N, INFO
INTEGER*8 IPIVOT(*)
REAL AP(*), WORK(*)




F95 INTERFACE
SUBROUTINE SPTRI(UPLO, N, AP, IPIVOT, WORK, INFO)

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

SUBROUTINE SPTRI_64(UPLO, N, AP, IPIVOT, WORK, INFO)

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




C INTERFACE
#include <sunperf.h>

void ssptri(char uplo, int n, float *a, int *ipivot, int *info);

void ssptri_64(char uplo, long n, float *a, long *ipivot, long *info);

Description

Oracle Solaris Studio Performance Library                           ssptri(3P)



NAME
       ssptri - compute the inverse of a real symmetric indefinite matrix A in
       packed storage using the factorization A = U*D*U**T  or  A  =  L*D*L**T
       computed by SSPTRF


SYNOPSIS
       SUBROUTINE SSPTRI(UPLO, N, AP, IPIVOT, WORK, INFO)

       CHARACTER*1 UPLO
       INTEGER N, INFO
       INTEGER IPIVOT(*)
       REAL AP(*), WORK(*)

       SUBROUTINE SSPTRI_64(UPLO, N, AP, IPIVOT, WORK, INFO)

       CHARACTER*1 UPLO
       INTEGER*8 N, INFO
       INTEGER*8 IPIVOT(*)
       REAL AP(*), WORK(*)




   F95 INTERFACE
       SUBROUTINE SPTRI(UPLO, N, AP, IPIVOT, WORK, INFO)

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

       SUBROUTINE SPTRI_64(UPLO, N, AP, IPIVOT, WORK, INFO)

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




   C INTERFACE
       #include <sunperf.h>

       void ssptri(char uplo, int n, float *a, int *ipivot, int *info);

       void ssptri_64(char uplo, long n, float *a, long *ipivot, long *info);



PURPOSE
       ssptri  computes the inverse of a real symmetric indefinite matrix A in
       packed storage using the factorization A = U*D*U**T  or  A  =  L*D*L**T
       computed by SSPTRF.


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.


       AP (input/output)
                 Real  array, dimension (N*(N+1)/2) On entry, the block diago-
                 nal matrix D and the multipliers used to obtain the factor  U
                 or  L  as  computed  by SSPTRF, stored as a packed triangular
                 matrix.

                 On exit, if INFO = 0, the (symmetric) inverse of the original
                 matrix, stored as a packed triangular matrix. The j-th column
                 of inv(A) is stored in the array AP as  follows:  if  UPLO  =
                 'U',  AP(i  + (j-1)*j/2) = inv(A)(i,j) for 1<=i<=j; if UPLO =
                 'L', AP(i + (j-1)*(2n-j)/2) = inv(A)(i,j) for j<=i<=n.


       IPIVOT (input)
                 Integer array, dimension (N) Details of the interchanges  and
                 the block structure of D as determined by SSPTRF.


       WORK (workspace)
                 Real array, 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                        ssptri(3P)