sla_porpvgrw (3p)

Name

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

Synopsis

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


CHARACTER*1 UPLO

INTEGER NCOLS, LDA, LDAF

REAL A(LDA,*), AF(LDAF,*), WORK(*)


REAL FUNCTION SLA_PORPVGRW_64(UPLO, NCOLS, A, LDA, AF, LDAF, WORK)


CHARACTER*1 UPLO

INTEGER*8 NCOLS, LDA, LDAF

REAL A(LDA,*), AF(LDAF,*), WORK(*)


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


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

INTEGER :: NCOLS, LDA, LDAF

CHARACTER(LEN=1) :: UPLO

REAL, DIMENSION(:) :: WORK


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


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

INTEGER(8) :: NCOLS, LDA, LDAF

CHARACTER(LEN=1) :: UPLO

REAL, DIMENSION(:) :: WORK


C INTERFACE
#include <sunperf.h>

float sla_porpvgrw (char uplo, int ncols, float *a, int lda, float *af,
int ldaf);

float sla_porpvgrw_64 (char uplo, long ncols, float *a, long lda, float
*af, long ldaf);

Description

Oracle Solaris Studio Performance Library                     sla_porpvgrw(3P)



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


SYNOPSIS
       REAL FUNCTION SLA_PORPVGRW(UPLO, NCOLS, A, LDA, AF, LDAF, WORK)


       CHARACTER*1 UPLO

       INTEGER NCOLS, LDA, LDAF

       REAL A(LDA,*), AF(LDAF,*), WORK(*)


       REAL FUNCTION SLA_PORPVGRW_64(UPLO, NCOLS, A, LDA, AF, LDAF, WORK)


       CHARACTER*1 UPLO

       INTEGER*8 NCOLS, LDA, LDAF

       REAL A(LDA,*), AF(LDAF,*), WORK(*)


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


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

       INTEGER :: NCOLS, LDA, LDAF

       CHARACTER(LEN=1) :: UPLO

       REAL, DIMENSION(:) :: WORK


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


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

       INTEGER(8) :: NCOLS, LDA, LDAF

       CHARACTER(LEN=1) :: UPLO

       REAL, DIMENSION(:) :: WORK


   C INTERFACE
       #include <sunperf.h>

       float sla_porpvgrw (char uplo, int ncols, float *a, int lda, float *af,
                 int ldaf);

       float sla_porpvgrw_64 (char uplo, long ncols, float *a, long lda, float
                 *af, long ldaf);


PURPOSE
       sla_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 REAL 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 REAL 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 SPOTRF.


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


       WORK (input)
                 WORK is REAL array, dimension (2*N)




                                  7 Nov 2015                  sla_porpvgrw(3P)