From help-octave-request at bevo dot che dot wisc dot edu  Fri Nov 14 01:48:12 1997
Subject: Re: Memory limits
From: Al Goldstein <al at hadamard dot math dot washington dot edu>
To: "John W. Eaton" <jwe at bevo dot che dot wisc dot edu>
cc: John Logsdon <j dot logsdon at lancaster dot ac dot uk>, help-octave@bevo.che.wisc.edu
Date: Thu, 13 Nov 1997 23:48:39 -0800 (PST)

Here is a different memory complaint.

I want the QR decomposition of an mxn matrix as given by dgeqrf in
lapack. As an example using dgeqrf in a fortran code I can solve
a problem with m=850,000 and n=5. With octave I'm limited to m=2000 before
memory runs out (64meg). One problem here is that Q is returned in octave
as an mxm matrix rather than an mxn matrix. Matlab does this also. But the
function orth does no better in octave. Orth returns mxn and still chokes at
m=2000, Matlab does not choke. For QR a hook is needed so that one can specify 
the return of an mxn matrix.