zla_herpvgrw.f

Section: LAPACK (3)
Updated: Tue Nov 14 2017
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NAME

zla_herpvgrw.f  

SYNOPSIS


 

Functions/Subroutines


double precision function zla_herpvgrw (UPLO, N, INFO, A, LDA, AF, LDAF, IPIV, WORK)
ZLA_HERPVGRW  

Function/Subroutine Documentation

 

double precision function zla_herpvgrw (character*1 UPLO, integer N, integer INFO, complex*16, dimension( lda, * ) A, integer LDA, complex*16, dimension( ldaf, * ) AF, integer LDAF, integer, dimension( * ) IPIV, double precision, dimension( * ) WORK)

ZLA_HERPVGRW

Purpose:

 ZLA_HERPVGRW 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
 (equilibrated) matrix A could be poor. This also means that the
 solution X, estimated condition numbers, and error bounds could be
 unreliable.


 

Parameters:

UPLO

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


N

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


INFO

          INFO is INTEGER
     The value of INFO returned from ZHETRF, .i.e., the pivot in
     column INFO is exactly 0.


A

          A is COMPLEX*16 array, dimension (LDA,N)
     On entry, the N-by-N matrix A.


LDA

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


AF

          AF is COMPLEX*16 array, dimension (LDAF,N)
     The block diagonal matrix D and the multipliers used to
     obtain the factor U or L as computed by ZHETRF.


LDAF

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


IPIV

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


WORK

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


 

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

June 2016

Definition at line 125 of file zla_herpvgrw.f.  

Author

Generated automatically by Doxygen for LAPACK from the source code.


 

Index

NAME
SYNOPSIS
Functions/Subroutines
Function/Subroutine Documentation
double precision function zla_herpvgrw (character*1 UPLO, integer N, integer INFO, complex*16, dimension( lda, * ) A, integer LDA, complex*16, dimension( ldaf, * ) AF, integer LDAF, integer, dimension( * ) IPIV, double precision, dimension( * ) WORK)
Author