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