sgesc2.f - Man Page

subroutine sgesc2 (n, a, lda, rhs, ipiv, jpiv, scale)
SGESC2 solves a system of linear equations using the LU factorization with complete pivoting computed by sgetc2.

SGESC2 solves a system of linear equations using the LU factorization with complete pivoting computed by sgetc2.  

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.

Parameters

N

          N is INTEGER
          The order of the matrix A.

A

          A is 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

LDA

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

RHS

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

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Contributors:

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

Definition at line 113 of file sgesc2.f.