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Livre :
Expressions régulières,
Syntaxe et mise en oeuvre :

ISBN : 978-2-7460-9712-4
EAN : 9782746097124
(Editions ENI)

GNU/Linux	CentOS 4.8	i386
	dgesc2(l)

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DGESC2

NAME
SYNOPSIS
PURPOSE
ARGUMENTS
FURTHER DETAILS

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NAME

DGESC2 - solve a system of linear equations A * X = scale* RHS with a general N-by-N matrix A using the LU factorization with complete pivoting computed by DGETC2

SYNOPSIS

	SUBROUTINE DGESC2(		N, A, LDA, RHS, IPIV, JPIV, SCALE )
	INTEGER		LDA, N
	DOUBLE		PRECISION SCALE
	INTEGER		IPIV( * ), JPIV( * )
	DOUBLE		PRECISION A( LDA, * ), RHS( * )

PURPOSE

DGESC2 solves a system of linear equations A * X = scale* RHS with a general N-by-N matrix A using the LU factorization with complete pivoting computed by DGETC2.

ARGUMENTS

N (input) INTEGER

The order of the matrix A.

A (input) DOUBLE PRECISION array, dimension (LDA,N)

On entry, the LU part of the factorization of the n-by-n matrix A computed by DGETC2: A = P * L * U * Q

LDA (input) INTEGER

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

RHS (input/output) DOUBLE PRECISION array, dimension (N).

On entry, the right hand side vector b. On exit, the solution vector X.

IPIV (iput) INTEGER array, dimension (N).

The pivot indices; for 1 <= i <= N, row i of the matrix has been interchanged with row IPIV(i).

JPIV (iput) INTEGER array, dimension (N).

The pivot indices; for 1 <= j <= N, column j of the matrix has been interchanged with column JPIV(j).

SCALE (output) DOUBLE PRECISION

On exit, SCALE contains the scale factor. SCALE is chosen 0 <= SCALE <= 1 to prevent owerflow in the solution.

FURTHER DETAILS

Based on contributions by
Bo Kagstrom and Peter Poromaa, Department of Computing Science,
Umea University, S-901 87 Umea, Sweden.

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dgesc2(l)