PCDTTRF - compute a LU factorization of an N-by-N complex tridiagonal diagonally dominant-like

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

       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.

LAPACK version 1.5                                 12 May 1997                                        PCDTTRF(l)

       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( * )