dgesc2.f man page

subroutine dgesc2 (N, A, LDA, RHS, IPIV, JPIV, SCALE)
DGESC2 solves a system of linear equations using the LU factorization with complete pivoting computed by sgetc2.

DGESC2 solves a system of linear equations using the LU factorization with complete pivoting computed by sgetc2.  

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.

Parameters:

N

          N is INTEGER
          The order of the matrix A.

A

          A is 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

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

RHS

          RHS is DOUBLE PRECISION array, dimension (N).
          On entry, the right hand side vector b.
          On exit, the solution vector X.

IPIV

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

JPIV

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

SCALE

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

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

November 2017

Contributors:

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

Definition at line 116 of file dgesc2.f.