GSP
Quick Navigator

Search Site

Unix VPS
A - Starter
B - Basic
C - Preferred
D - Commercial
MPS - Dedicated
Previous VPSs
* Sign Up! *

Support
Contact Us
Online Help
Handbooks
Domain Status
Man Pages

FAQ
Virtual Servers
Pricing
Billing
Technical

Network
Facilities
Connectivity
Topology Map

Miscellaneous
Server Agreement
Year 2038
Credits
 

USA Flag

 

 

Man Pages
PZGBTRF(l) ) PZGBTRF(l)

PZGBTRF - compute a LU factorization of an N-by-N complex banded distributed matrix with bandwidth BWL, BWU

SUBROUTINE PZGBTRF(
N, BWL, BWU, A, JA, DESCA, IPIV, AF, LAF, WORK, LWORK, INFO )
INTEGER BWL, BWU, INFO, JA, LAF, LWORK, N INTEGER DESCA( * ), IPIV( * ) COMPLEX*16 A( * ), AF( * ), WORK( * )

PZGBTRF computes a LU factorization of an N-by-N complex banded distributed matrix with bandwidth BWL, BWU: 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 PZGBTRS to solve linear systems.
 
The factorization has the form
 

P A(1:N, JA:JA+N-1) Q = L U
 
where U is a banded upper triangular matrix and L is banded lower triangular, and P and Q are permutation matrices.
 
The matrix Q represents reordering of columns
 
for parallelism's sake, while P represents
 
reordering of rows for numerical stability using
 
classic partial pivoting.
 
13 August 2001 ScaLAPACK version 1.7

Search for    or go to Top of page |  Section l |  Main Index

Powered by GSP Visit the GSP FreeBSD Man Page Interface.
Output converted with ManDoc.