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From: "Ana " <filter_world@yahoo.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: bilinear transformation
Date: Sat, 7 Nov 2009 18:15:05 +0000 (UTC)
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hi there,

 %fp = 2*pi*2e03; For prewarping
 fs = 20e03;
 s = tf('s');
 num = 1;
 den = [1 1.414 1 ];
 
 [numd,dend] = bilinear(num,den,fs)
 
 
z= [1:0.1:20]';
m = filter(numd,dend,z)

freqz(m)

It seems that it is working now, if i understood well the command freqz is used to give the response of discrete time systems, like digital systems does this therefore mean that when obtianing the plot from the code above, I am getting the frequency response of a digital filter in this case the butterworth? Thanks alot for any help.

Regards,
Ana