Go to main content
Oracle Developer Studio 12.5 Man Pages

Exit Print View

Updated: June 2017
 
 

dla_syrpvgrw (3p)

Name

dla_syrpvgrw - compute the reciprocal pivot growth factor norm(A)/norm(U) for a symmetric indefinite matrix

Synopsis

DOUBLE PRECISION FUNCTION DLA_SYRPVGRW(UPLO, N, INFO, A, LDA, AF, LDAF,
IPIV, WORK)


CHARACTER*1 UPLO

INTEGER N, INFO, LDA, LDAF

INTEGER IPIV(*)

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


DOUBLE  PRECISION  FUNCTION  DLA_SYRPVGRW_64(UPLO, N, INFO, A, LDA, AF,
LDAF, IPIV, WORK)


CHARACTER*1 UPLO

INTEGER*8 N, INFO, LDA, LDAF

INTEGER*8 IPIV(*)

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


F95 INTERFACE
REAL(8) FUNCTION LA_SYRPVGRW(UPLO, N, INFO, A,  LDA,  AF,  LDAF,  IPIV,
WORK)


INTEGER :: N, INFO, LDA, LDAF

CHARACTER(LEN=1) :: UPLO

INTEGER, DIMENSION(:) :: IPIV

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

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


REAL(8)  FUNCTION LA_SYRPVGRW_64(UPLO, N, INFO, A, LDA, AF, LDAF, IPIV,
WORK)


INTEGER(8) :: N, INFO, LDA, LDAF

CHARACTER(LEN=1) :: UPLO

INTEGER(8), DIMENSION(:) :: IPIV

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

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


C INTERFACE
#include <sunperf.h>

double dla_syrpvgrw (char uplo, int n, int info, double  *a,  int  lda,
double *af, int ldaf, int *ipiv);

Description

Oracle Solaris Studio Performance Library                     dla_syrpvgrw(3P)



NAME
       dla_syrpvgrw   -   compute   the   reciprocal   pivot   growth   factor
       norm(A)/norm(U) for a symmetric indefinite matrix


SYNOPSIS
       DOUBLE PRECISION FUNCTION DLA_SYRPVGRW(UPLO, N, INFO, A, LDA, AF, LDAF,
                 IPIV, WORK)


       CHARACTER*1 UPLO

       INTEGER N, INFO, LDA, LDAF

       INTEGER IPIV(*)

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


       DOUBLE  PRECISION  FUNCTION  DLA_SYRPVGRW_64(UPLO, N, INFO, A, LDA, AF,
                 LDAF, IPIV, WORK)


       CHARACTER*1 UPLO

       INTEGER*8 N, INFO, LDA, LDAF

       INTEGER*8 IPIV(*)

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


   F95 INTERFACE
       REAL(8) FUNCTION LA_SYRPVGRW(UPLO, N, INFO, A,  LDA,  AF,  LDAF,  IPIV,
                 WORK)


       INTEGER :: N, INFO, LDA, LDAF

       CHARACTER(LEN=1) :: UPLO

       INTEGER, DIMENSION(:) :: IPIV

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

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


       REAL(8)  FUNCTION LA_SYRPVGRW_64(UPLO, N, INFO, A, LDA, AF, LDAF, IPIV,
                 WORK)


       INTEGER(8) :: N, INFO, LDA, LDAF

       CHARACTER(LEN=1) :: UPLO

       INTEGER(8), DIMENSION(:) :: IPIV

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

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


   C INTERFACE
       #include <sunperf.h>

       double dla_syrpvgrw (char uplo, int n, int info, double  *a,  int  lda,
                 double *af, int ldaf, int *ipiv);




PURPOSE
       dla_syrpvgrw    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.


       N (input)
                 N is INTEGER
                 The number of linear equations, i.e., the order of the matrix
                 A. N >= 0.


       INFO (input)
                 INFO is INTEGER
                 The value of INFO returned from DSYTRF, i.e.,  the  pivot  in
                 column INFO is exactly 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  block  diagonal  matrix  D  and  the multipliers used to
                 obtain the factor U or L as computed by DSYTRF.


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


       IPIV (input)
                 IPIV is INTEGER array, dimension (N)
                 Details of the interchanges and the block structure of  D  as
                 determined by DSYTRF.


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




                                  7 Nov 2015                  dla_syrpvgrw(3P)