dtrcon (3p)

Name

dtrcon - lar matrix A, in either the 1-norm or the infinity-norm

Synopsis

SUBROUTINE DTRCON(NORM, UPLO, DIAG, N, A, LDA, RCOND, WORK, WORK2,
INFO)

CHARACTER*1 NORM, UPLO, DIAG
INTEGER N, LDA, INFO
INTEGER WORK2(*)
DOUBLE PRECISION RCOND
DOUBLE PRECISION A(LDA,*), WORK(*)

SUBROUTINE DTRCON_64(NORM, UPLO, DIAG, N, A, LDA, RCOND, WORK, WORK2,
INFO)

CHARACTER*1 NORM, UPLO, DIAG
INTEGER*8 N, LDA, INFO
INTEGER*8 WORK2(*)
DOUBLE PRECISION RCOND
DOUBLE PRECISION A(LDA,*), WORK(*)




F95 INTERFACE
SUBROUTINE TRCON(NORM, UPLO, DIAG, N, A, LDA, RCOND, WORK, WORK2,
INFO)

CHARACTER(LEN=1) :: NORM, UPLO, DIAG
INTEGER :: N, LDA, INFO
INTEGER, DIMENSION(:) :: WORK2
REAL(8) :: RCOND
REAL(8), DIMENSION(:) :: WORK
REAL(8), DIMENSION(:,:) :: A

SUBROUTINE TRCON_64(NORM, UPLO, DIAG, N, A, LDA, RCOND, WORK,
WORK2, INFO)

CHARACTER(LEN=1) :: NORM, UPLO, DIAG
INTEGER(8) :: N, LDA, INFO
INTEGER(8), DIMENSION(:) :: WORK2
REAL(8) :: RCOND
REAL(8), DIMENSION(:) :: WORK
REAL(8), DIMENSION(:,:) :: A




C INTERFACE
#include <sunperf.h>

void dtrcon(char norm, char uplo, char diag, int n, double *a, int lda,
double *rcond, int *info);

void dtrcon_64(char norm, char uplo, char diag, long n, double *a, long
lda, double *rcond, long *info);

Description

Oracle Solaris Studio Performance Library                           dtrcon(3P)



NAME
       dtrcon  - estimate the reciprocal of the condition number of a triangu-
       lar matrix A, in either the 1-norm or the infinity-norm


SYNOPSIS
       SUBROUTINE DTRCON(NORM, UPLO, DIAG, N, A, LDA, RCOND, WORK, WORK2,
             INFO)

       CHARACTER*1 NORM, UPLO, DIAG
       INTEGER N, LDA, INFO
       INTEGER WORK2(*)
       DOUBLE PRECISION RCOND
       DOUBLE PRECISION A(LDA,*), WORK(*)

       SUBROUTINE DTRCON_64(NORM, UPLO, DIAG, N, A, LDA, RCOND, WORK, WORK2,
             INFO)

       CHARACTER*1 NORM, UPLO, DIAG
       INTEGER*8 N, LDA, INFO
       INTEGER*8 WORK2(*)
       DOUBLE PRECISION RCOND
       DOUBLE PRECISION A(LDA,*), WORK(*)




   F95 INTERFACE
       SUBROUTINE TRCON(NORM, UPLO, DIAG, N, A, LDA, RCOND, WORK, WORK2,
              INFO)

       CHARACTER(LEN=1) :: NORM, UPLO, DIAG
       INTEGER :: N, LDA, INFO
       INTEGER, DIMENSION(:) :: WORK2
       REAL(8) :: RCOND
       REAL(8), DIMENSION(:) :: WORK
       REAL(8), DIMENSION(:,:) :: A

       SUBROUTINE TRCON_64(NORM, UPLO, DIAG, N, A, LDA, RCOND, WORK,
              WORK2, INFO)

       CHARACTER(LEN=1) :: NORM, UPLO, DIAG
       INTEGER(8) :: N, LDA, INFO
       INTEGER(8), DIMENSION(:) :: WORK2
       REAL(8) :: RCOND
       REAL(8), DIMENSION(:) :: WORK
       REAL(8), DIMENSION(:,:) :: A




   C INTERFACE
       #include <sunperf.h>

       void dtrcon(char norm, char uplo, char diag, int n, double *a, int lda,
                 double *rcond, int *info);

       void dtrcon_64(char norm, char uplo, char diag, long n, double *a, long
                 lda, double *rcond, long *info);



PURPOSE
       dtrcon estimates the reciprocal of the condition number of a triangular
       matrix A, in either the 1-norm or the infinity-norm.

       The norm of A is computed and an estimate is obtained for norm(inv(A)),
       then the reciprocal of the condition number is computed as
          RCOND = 1 / ( norm(A) * norm(inv(A)) ).


ARGUMENTS
       NORM (input)
                 Specifies whether the 1-norm condition number or  the  infin-
                 ity-norm condition number is required:
                 = '1' or 'O':  1-norm;
                 = 'I':         Infinity-norm.


       UPLO (input)
                 = 'U':  A is upper triangular;
                 = 'L':  A is lower triangular.


       DIAG (input)
                 = 'N':  A is non-unit triangular;
                 = 'U':  A is unit triangular.


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


       A (input) The  triangular  matrix A.  If UPLO = 'U', the leading N-by-N
                 upper triangular part of the array A contains the upper  tri-
                 angular  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.


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


       RCOND (output)
                 The reciprocal of the condition number of the matrix A,  com-
                 puted as RCOND = 1/(norm(A) * norm(inv(A))).


       WORK (workspace)
                 dimension(3*N)

       WORK2 (workspace)
                 dimension(N)

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




                                  7 Nov 2015                        dtrcon(3P)