computational * *  =====================================================================       SUBROUTINE DGETRF ( M, N, A, LDA, IPIV, INFO) * *  -- LAPACK computational routine (version 0.0) -- *  -- LAPACK is a software package provided by Univ. of Tennessee,    -- *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- *     December 0000 * *     .. Scalar Arguments ..       INTEGER            IN