dtrti2 (3p)

Name

dtrti2 - compute the inverse of a real upper or lower triangular matrix

Synopsis

SUBROUTINE DTRTI2(UPLO, DIAG, N, A, LDA, INFO)

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

SUBROUTINE DTRTI2_64(UPLO, DIAG, N, A, LDA, INFO)

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




F95 INTERFACE
SUBROUTINE TRTI2(UPLO, DIAG, N, A, LDA, INFO)

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

SUBROUTINE TRTI2_64(UPLO, DIAG, N, A, LDA, INFO)

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




C INTERFACE
#include <sunperf.h>

void dtrti2(char uplo, char diag,  int  n,  double  *a,  int  lda,  int
*info);

void  dtrti2_64(char uplo, char diag, long n, double *a, long lda, long
*info);

Description

Oracle Solaris Studio Performance Library                           dtrti2(3P)



NAME
       dtrti2 - compute the inverse of a real upper or lower triangular matrix


SYNOPSIS
       SUBROUTINE DTRTI2(UPLO, DIAG, N, A, LDA, INFO)

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

       SUBROUTINE DTRTI2_64(UPLO, DIAG, N, A, LDA, INFO)

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




   F95 INTERFACE
       SUBROUTINE TRTI2(UPLO, DIAG, N, A, LDA, INFO)

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

       SUBROUTINE TRTI2_64(UPLO, DIAG, N, A, LDA, INFO)

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




   C INTERFACE
       #include <sunperf.h>

       void dtrti2(char uplo, char diag,  int  n,  double  *a,  int  lda,  int
                 *info);

       void  dtrti2_64(char uplo, char diag, long n, double *a, long lda, long
                 *info);



PURPOSE
       dtrti2 computes the inverse of a real upper or lower triangular matrix.

       This is the Level 2 BLAS version of the algorithm.


ARGUMENTS
       UPLO (input)
                 Specifies  whether the matrix A is upper or lower triangular.
                 = 'U':  Upper triangular
                 = 'L':  Lower triangular


       DIAG (input)
                 Specifies whether or not the matrix A is unit triangular.   =
                 'N':  Non-unit triangular
                 = 'U':  Unit triangular


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


       A (input/output)
                 On  entry, the triangular matrix A.  If UPLO = 'U', the lead-
                 ing n by n upper triangular part of the array A contains  the
                 upper  triangular  matrix,  and the strictly lower triangular
                 part of A is not referenced.  If UPLO = 'L', the leading n by
                 n  lower  triangular  part  of the array A contains the lower
                 triangular matrix, and the strictly upper triangular part  of
                 A is not referenced.  If DIAG = 'U', the diagonal elements of
                 A are also not referenced and are assumed to be 1.

                 On exit, the (triangular) inverse of the original matrix,  in
                 the same storage format.


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


       INFO (output)
                 = 0: successful exit
                 < 0: if INFO = -k, the k-th argument had an illegal value




                                  7 Nov 2015                        dtrti2(3P)