pzdttrf (3)

Compute a lu factorization of an n-by-n complex tridiagonal diagonally dominant-like distributed matrix a(1:n, ja:ja+n-1)

  1. Carta.tech
  2. Man Pages
  3. Library calls
  4. pzdttrf: Compute a lu factorization of an n-by-n complex tridiagonal diagonally dominant-like distributed matrix a(1:n, ja:ja+n-1)
  1. Carta.tech
  2. Packages
  3. scalapack-doc
  4. pzdttrf: 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 PZDTTRF(

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

INTEGER

INFO, JA, LAF, LWORK, N

INTEGER

DESCA( * )

COMPLEX*16

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

PURPOSE

PZDTTRF 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 PZDTTRS 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.