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.TH SGESC2 l "15 June 2000" "LAPACK version 3.0" ")"
.SH NAME
SGESC2 - 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 SGETC2
.SH SYNOPSIS
.TP 19
SUBROUTINE SGESC2(
N, A, LDA, RHS, IPIV, JPIV, SCALE )
.TP 19
.ti +4
INTEGER
LDA, N
.TP 19
.ti +4
REAL
SCALE
.TP 19
.ti +4
INTEGER
IPIV( * ), JPIV( * )
.TP 19
.ti +4
REAL
A( LDA, * ), RHS( * )
.SH PURPOSE
SGESC2 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 SGETC2.
.SH ARGUMENTS
.TP 8
N (input) INTEGER
The order of the matrix A.
.TP 8
A (input) REAL array, dimension (LDA,N)
On entry, the LU part of the factorization of the n-by-n
matrix A computed by SGETC2: A = P * L * U * Q
.TP 8
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1, N).
.TP 8
RHS (input/output) REAL array, dimension (N).
On entry, the right hand side vector b.
On exit, the solution vector X.
.TP 8
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).
.TP 8
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).
.TP 9
SCALE (output) REAL
On exit, SCALE contains the scale factor. SCALE is chosen
0 <= SCALE <= 1 to prevent owerflow in the solution.
.SH FURTHER DETAILS
Based on contributions by
.br
Bo Kagstrom and Peter Poromaa, Department of Computing Science,
Umea University, S-901 87 Umea, Sweden.
.br
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