From help-octave-request at bevo dot che dot wisc dot edu  Mon Jan 17 01:04:28 2000
Subject: LU Factorization: A = P'*L*U ?
From: "Vivek Shanmuganathan \(95410006-BS\)" <viveks at me dot iitb dot ernet dot in>
To: help-octave at bevo dot che dot wisc dot edu
Date: Mon, 17 Jan 2000 12:32:16 +0530 (IST)

Hello:

What is the Octave definition of LU-Factorisation of a
matrix A? As I understand from LAPACK documentation, the
factorisation is defined as

	A = P*L*U	......	(1)

where U is upper diagonal, L is unit lower diagonal, and P
is the permutation matrix (unit matrix with rows
interchanged suitably to satisfy equation (1)). 

However, the value of the permutation matrix retuned by
Octave 2.0.14 (i386-redhat-linux-gnu) is actually
transpose(P) as given in (1).

Any comments?

Vivek...



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