From help-request at octave dot org Sun Jul 24 09:49:23 2005
Subject: Re: mean filter, another implementation
From: =?ISO-8859-1?Q?S=F8ren_Hauberg?= <soren at hauberg dot org>
To: help at octave dot org
Date: Sun, 24 Jul 2005 16:48:19 +0200

Hi Everybody,
First I wanted to say thanks for all you help. I've implementing a fast 
mean filtering in C++, and wanted to give you some results (the function 
names are the ones that was given in previous mails, and mymeanfilter is 
my implementation in C++):

data = rand(1, 10^7);
n = 100;
f = ones(1,n)/n;

tic; mymeanfilter(data,n); toc   ans = 2.9098
tic; meanfilter(data,n); toc     ans = 14.860
tic; rec_mean1(data,n); toc      ans = 12.704
tic; rec_mean2(data,n); toc      ans = 4.4931
tic; rec_mean3(data,n); toc      ans = 11.573
tic; conv(data, f); toc          ans = 10.463

So the solution (rec_mean2) by Andreas Naessl was quite good, only a 
little bit slower than the C++ implementation.

Thanks Everybody,
Søren

P.S. If anybody wants my code, you can get it at
http://hauberg.org/share/files/meanfilter.cc



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