DGESC2(3)      LAPACK routine of NEC Numeric Library Collection      DGESC2(3)



NAME
       DGESC2

SYNOPSIS
       SUBROUTINE DGESC2 (N, A, LDA, RHS, IPIV, JPIV, SCALE)



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)
                     N is INTEGER
                     The order of the matrix A.

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

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

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



LAPACK routine                  31 October 2017                      DGESC2(3)