pcdttrf(3) debian man page | unix.com

PCDTTRF(l)						   LAPACK routine (version 1.5) 						PCDTTRF(l)

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.

LAPACK version 1.5						    12 May 1997 							PCDTTRF(l)