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Re:
From: |
Shai Ayal |
Subject: |
Re: |
Date: |
Mon, 27 Mar 2006 18:53:05 +0200 |
User-agent: |
Thunderbird 1.5 (Windows/20051201) |
Francesco Potorti` wrote:
I think this is a real-world problem. It is probably the biggest flaw in
the matlab language, making you write programs which use unintuitive and
hard to understand tricks just to avoid for-loops. As a real world
example, have a look at the code for hist.m in octave. Instead of a ~N
for-loop, it uses NlogN sorting just because sort is done in C and thus
is faster.
I don't really think that this is a flaw. The Octave (Matlab) language
is a matrix language, which is duly optimised for doing matrix
computations. This is exactly what one would expect from a matrix
language. Being fast at doing non-matrix operations is certainly an
added benefit, not the foremost objective of the language.
Do you agree?
I agree. I use octave because of these benifits.
I think that for-loops are an essential part of any programming
language, and avoiding them has unfortunately become the hallmark of
good matlab programming. When conducting job interviews for positions
for which matlab/octave is relevant, one of my questions is:
how would you calculate a 10 sample running average on a 100 element vector?
I wouldn't say that using a for loop for such a small vector is wrong,
unless the operation is to be done many times.
true, but I think someone who has some experience with matlab/octave
will understand at once that this question is all about avoiding the
for-loop
Shai
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- Re: octave loop slowness (was ""), (continued)
- Re: octave loop slowness (was ""), Brendan Drew, 2006/03/20
- Re: octave loop slowness (was ""), Bill Denney, 2006/03/20
- Re: octave loop slowness (was ""), John W. Eaton, 2006/03/21
- Re: octave loop slowness (was ""), Brendan Drew, 2006/03/21
- Re: octave loop slowness (was ""), Przemek Klosowski, 2006/03/22
- Re: octave loop slowness (was ""), Joshua Rigler, 2006/03/20
Re:, Arvid Rosén, 2006/03/19
- Re:, Shai Ayal, 2006/03/19
- Re:, Francesco Potorti`, 2006/03/27
- Re:, Stefan van der Walt, 2006/03/27
- Re:,
Shai Ayal <=
- Re:, Keith Goodman, 2006/03/27