From help-octave-request at che dot utexas dot edu  Tue May  2 23:03:38 1995
Subject: Re: Performance: Octave vs. Matlab
From: wkim+ at pitt dot edu
To: "John Eaton" <jwe at che dot utexas dot edu>
Cc: "Octave Users" <help-octave at che dot utexas dot edu>
Date: Tue, 02 May 95 16:54:45 -0400

> Date: Tue, 02 May 95 12:47:41 -0400
> From: "John Eaton" <jwe at che dot utexas dot edu>
> 
> wkim+ at pitt dot edu wrote:
> 
> :...
> : A free software can be slower or faster than a commercial product,
> : but 3X slower speed was too big for me to understand.
> 
> Why?
> 
> : With such slow speed, I doubt I would use octave in a real application.
> 
> Why not?  There are many things that Octave does that are as fast or
> faster than Matlab, and even some things that Octave can do that
> Matlab can't.
> I think there are many reasons to choose to use Octave that have
> nothing to do with speed.  In fact, if you are after really fast
> solutions, any interpreted language like Octave, RLaB, Scilab, Matlab,
> or U-Name-it-Lab :-), is probably not your best bet anyway.

Yes, of course there are many reasons to use an interpreter for
simple simulations instead of writing programs in C, C++, etc..  
Why not wishing to have a faster one when we have several 
choices of similar interpreters?  I agree that Octave has things 
that Matlab can't offer, but the reverse is also true.  As long as
both packages can fit my needs, more or less features are not major 
factor (at least to me) in choosing one.  An interpreter is an 
interpreter (nothing but an interpreter :-)) and is usually for 
simple simulations (unless it can generate an executable).
A good thing of octave is it's 'free' (THANKS!).  When I can use
Matlab (site-licensed), a big preformance gap could affect my 
choice.

Here is a session of Matlab:

¯ tic; bench1(10); toc

elapsed_time =

   11.0900

¯ 

The bench1.m was
----------------------------
function [z] = bench1 (n)
for i=1:n,
    for j=1:1000,
        z=log(j);
        z1=log(j+1);
        z2=log(j+2);
        z3=log(j+3);
        z4=log(j+4);
        z5=log(j+5);
        z6=log(j+6);
        z7=log(j+7);
        z8=log(j+8);
        z9=log(j+9);
    end
end
z = z9;
----------------------------

And, for the same program (translated keywords only), octave 1.1.0 for
OS/2 gave 32 seconds which is about 3 times slower than Matlab for Win.
and cannot be said as "slight" overheads.  How do you think?

BTW, I found there exists ver. 1.1.1, but my OS/2 version is 1.1.0.
Can I expect a newer version of octave for OS/2 soon?
(There were bugs in octave 1.1.0.)
Can I have getl() function like the one in Matlab?

Thank you.

//--------------------------------------------------------------------
// Wonkoo Kim
// wkim+ at pitt dot edu