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From: "Steve Amphlett" <Firstname.Lastname@Where-I-Work.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Speed Comparison
Date: Sun, 12 Apr 2009 12:29:01 +0000 (UTC)
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"Chaos" <rothko.fan@gmail.com> wrote in message <grpt1t$i1e$1@fred.mathworks.com>...
> "Sky " <theskyishigh@yahoo.com> wrote in message <grokia$rcq$1@fred.mathworks.com>...
> > I have ported a code from FORTRAN95 to MATLAB. Replicated it almost exactly. About 500 lines in length, it contains a lot of double precision arithmetic and nested iterations. Very little linear algebra.
> > 
> > Under MATLAB R2008b it executes in 7.3 seconds. Compiled under Compaq Visual Fortran 6 it takes 375 milliseconds. Under the Intel Fortran 11 compiler, it takes 473 MICROseconds. These times are for a WinXP system, Core 2 Duo 2 GHz (4MB L2 Cache), 2GB RAM...
> > 
> > Is this possible? Is MATLAB this slow or am I doing something wrong?
> 
> CVF -> no OpenMP, no SSE2, no SSE3, no parallelzation, no Real(16), old version of IMSL

True, but it still doesn't add up to a 1000 speed multiplier.  OpenMP for a 2 CPU, maybe 1.7x, SSE2 and/or SSE3, maybe 2x more.

If I saw these ratios, I'd be woderring if we were comparing bebug with mega-complied code.

The outputs of some profiling tests would be interesting.