dla_porpvgrw (3p)

Name

dla_porpvgrw - compute the reciprocal pivot growth factor norm(A)/norm(U) for a symmetric or Hermitian positive-definite matrix

Synopsis

DOUBLE PRECISION FUNCTION DLA_PORPVGRW(UPLO, NCOLS, A, LDA, AF,   LDAF,
WORK)


CHARACTER*1 UPLO

INTEGER NCOLS, LDA, LDAF

DOUBLE PRECISION A(LDA,*), AF(LDAF,*), WORK(*)


DOUBLE  PRECISION  FUNCTION  DLA_PORPVGRW_64(UPLO,  NCOLS,  A, LDA, AF,
LDAF, WORK)


CHARACTER*1 UPLO

INTEGER*8 NCOLS, LDA, LDAF

DOUBLE PRECISION A(LDA,*), AF(LDAF,*), WORK(*)


F95 INTERFACE
REAL(8) FUNCTION LA_PORPVGRW(UPLO, NCOLS, A, LDA, AF, LDAF, WORK)


INTEGER :: NCOLS, LDA, LDAF

CHARACTER(LEN=1) :: UPLO

REAL(8), DIMENSION(:,:) :: A, AF

REAL(8), DIMENSION(:) :: WORK


REAL(8) FUNCTION LA_PORPVGRW_64(UPLO, NCOLS, A, LDA, AF, LDAF, WORK)


INTEGER(8) :: NCOLS, LDA, LDAF

CHARACTER(LEN=1) :: UPLO

REAL(8), DIMENSION(:,:) :: A, AF

REAL(8), DIMENSION(:) :: WORK


C INTERFACE
#include <sunperf.h>

double dla_porpvgrw (char uplo, int ncols, double *a, int  lda,  double
*af, int ldaf);

double  dla_porpvgrw_64  (char  uplo,  long ncols, double *a, long lda,
double *af, long ldaf);

Description

Oracle Solaris Studio Performance Library                     dla_porpvgrw(3P)



NAME
       dla_porpvgrw   -   compute   the   reciprocal   pivot   growth   factor
       norm(A)/norm(U) for a symmetric or Hermitian positive-definite matrix


SYNOPSIS
       DOUBLE PRECISION FUNCTION DLA_PORPVGRW(UPLO, NCOLS, A, LDA, AF,   LDAF,
                 WORK)


       CHARACTER*1 UPLO

       INTEGER NCOLS, LDA, LDAF

       DOUBLE PRECISION A(LDA,*), AF(LDAF,*), WORK(*)


       DOUBLE  PRECISION  FUNCTION  DLA_PORPVGRW_64(UPLO,  NCOLS,  A, LDA, AF,
                 LDAF, WORK)


       CHARACTER*1 UPLO

       INTEGER*8 NCOLS, LDA, LDAF

       DOUBLE PRECISION A(LDA,*), AF(LDAF,*), WORK(*)


   F95 INTERFACE
       REAL(8) FUNCTION LA_PORPVGRW(UPLO, NCOLS, A, LDA, AF, LDAF, WORK)


       INTEGER :: NCOLS, LDA, LDAF

       CHARACTER(LEN=1) :: UPLO

       REAL(8), DIMENSION(:,:) :: A, AF

       REAL(8), DIMENSION(:) :: WORK


       REAL(8) FUNCTION LA_PORPVGRW_64(UPLO, NCOLS, A, LDA, AF, LDAF, WORK)


       INTEGER(8) :: NCOLS, LDA, LDAF

       CHARACTER(LEN=1) :: UPLO

       REAL(8), DIMENSION(:,:) :: A, AF

       REAL(8), DIMENSION(:) :: WORK


   C INTERFACE
       #include <sunperf.h>

       double dla_porpvgrw (char uplo, int ncols, double *a, int  lda,  double
                 *af, int ldaf);

       double  dla_porpvgrw_64  (char  uplo,  long ncols, double *a, long lda,
                 double *af, long ldaf);


PURPOSE
       dla_porpvgrw   computes   the   reciprocal    pivot    growth    factor
       norm(A)/norm(U).  The  "max  absolute element" norm is used. If this is
       much less than 1, the stability of the LU factorization of the (equili-
       brated)  matrix  A  could be poor. This also means that the solution X,
       estimated condition numbers, and error bounds could be unreliable.


ARGUMENTS
       UPLO (input)
                 UPLO is CHARACTER*1
                 = 'U':  Upper triangle of A is stored;
                 = 'L':  Lower triangle of A is stored.


       NCOLS (input)
                 NCOLS is INTEGER
                 The number of columns of the matrix A. NCOLS >= 0.


       A (input)
                 A is DOUBLE PRECISION array, dimension (LDA,N)
                 On entry, the N-by-N matrix A.


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


       AF (input)
                 AF is DOUBLE PRECISION array, dimension (LDAF,N)
                 The triangular factor U or L from the Cholesky  factorization
                 A=U**T*U or A=L*L**T, as computed by DPOTRF.


       LDAF (input)
                 LDAF is INTEGER
                 The leading dimension of the array AF.
                 LDAF >= max(1,N).


       WORK (input)
                 WORK is DOUBLE PRECISION array, dimension (2*N)




                                  7 Nov 2015                  dla_porpvgrw(3P)