sla_gerpvgrw.f man page

sla_gerpvgrw.f —

Synopsis

Functions/Subroutines

REAL function sla_gerpvgrw (N, NCOLS, A, LDA, AF, LDAF)
SLA_GERPVGRW

Function/Subroutine Documentation

REAL function sla_gerpvgrw (integerN, integerNCOLS, real, dimension( lda, * )A, integerLDA, real, dimension( ldaf, * )AF, integerLDAF)

SLA_GERPVGRW

Purpose:

SLA_GERPVGRW 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:

N

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

NCOLS

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

A

     A is REAL 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 REAL array, dimension (LDAF,N)
The factors L and U from the factorization
A = P*L*U as computed by SGETRF.

LDAF

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

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

November 2011

Definition at line 98 of file sla_gerpvgrw.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

sla_gerpvgrw(3) is an alias of sla_gerpvgrw.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK