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NAME

       PCDTTRF  -  compute a LU factorization of an N-by-N complex tridiagonal
       diagonally dominant-like distributed matrix A(1:N, JA:JA+N-1)

SYNOPSIS

       SUBROUTINE PCDTTRF( N, DL, D, DU, JA, DESCA, AF, LAF, WORK, LWORK, INFO
                           )

           INTEGER         INFO, JA, LAF, LWORK, N

           INTEGER         DESCA( * )

           COMPLEX         AF( * ), D( * ), DL( * ), DU( * ), WORK( * )

PURPOSE

       PCDTTRF  computes  a  LU factorization of an N-by-N complex tridiagonal
       diagonally  dominant-like   distributed   matrix   A(1:N,   JA:JA+N-1).
       Reordering  is used to increase parallelism in the factorization.  This
       reordering results in factors that are DIFFERENT from those produced by
       equivalent  sequential  codes. These factors cannot be used directly by
       users; however, they can be used in
       subsequent calls to PCDTTRS to solve linear systems.

       The factorization has the form

               P A(1:N, JA:JA+N-1) P^T = L U

       where U is a tridiagonal upper triangular matrix and L  is  tridiagonal
       lower triangular, and P is a permutation matrix.