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PSDTTRF(l)						   LAPACK routine (version 1.5) 						PSDTTRF(l)

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

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

	   INTEGER	   INFO, JA, LAF, LWORK, N

	   INTEGER	   DESCA( * )

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

PURPOSE
       PSDTTRF	computes a LU factorization of an N-by-N real tridiagonal diagonally dominant-like distributed matrix A(1:N, JA:JA+N-1).  Reorder-
       ing 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 PSDTTRS 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 							PSDTTRF(l)