SV: SV: [scilab-Users] lowpassfilter

[Anders Sneckenborg]

Hi Julio

How do you plot the freq response?

Regards
Anders

________________________________________
Från: Julio Gonzalez-Saenz [julio.gonzalez at ymail.com]
Skickat: den 15 april 2010 11:31
Till: users at lists.scilab.org
Ämne: Re: SV: [scilab-Users] lowpassfilter

Hi Anders,

I you plot the freq response of iir you see that the max value is around 0.75 same as your graphic shows.. I will take a closer look at the iir response..

Regards,

Julio Gonzalez-Saenz
www.part-time-scientists.com
www.neex-technologies.com

________________________________
From: Anders Sneckenborg <anders at simbalsyd.se>
To: "users at lists.scilab.org" <users at lists.scilab.org>
Sent: Thu, 15 April, 2010 7:14:38
Subject: SV: [scilab-Users] lowpassfilter

Hi again

I edited the code (removed dead code) and here it is again. It will execute exactly as before but without the disturbing dead code.

//---------------------------
f1 = 0.1;      //Hz
tSamp = 0.01;  //s
tMax = 200;

t = 0:tSamp:tMax;
y = sin(2*%pi*f1*t);

Order = 1;
Fcutoff = 0.1;
Fs = 1/tSamp;
hz = iir(Order,'lp','butt',[Fcutoff/Fs 0],[0 0]);
sl = tf2ss(hz);
yf = flts(y,sl);

plot(t,y,'-b');
plot(t,yf,'-r');
//---------------------------

/Anders


Från: Julio Gonzalez-Saenz [mailto:julio.gonzalez at ymail.com]
Skickat: den 14 april 2010 22:42
Till: users at lists.scilab.org
Ämne: Re: [scilab-Users] lowpassfilter

Hi Anders,

Can you please double check the semicolon on the function y definition? You also have a f1 and f2 but only f1 is defined..

Regards,


Julio Gonzalez-Saenz
www.part-time-scientists.com
www.neex-technologies.com


________________________________
From: Anders Sneckenborg <anders at simbalsyd.se>
To: "users at lists.scilab.org" <users at lists.scilab.org>
Sent: Wed, 14 April, 2010 22:19:29
Subject: [scilab-Users] lowpassfilter
Hi

When running the following script I expected the filtered signal to have an amplitude of 0.5.
My intention was to lowpassfilter a signal with the same frequency as the cutoff frequency.  Am I doing something wrong?

//---------------------------
f1 = 0.1;      //Hz
tSamp = 0.01;  //s
tMax = 200;

t = 0:tSamp:tMax;
y = 1*sin(2*%pi*f1*t);  + 0.5*sin(2*%pi*f2*t);

Order = 1;
Fcutoff = 0.1;
Fs = 1/tSamp;
hz = iir(Order,'lp','butt',[Fcutoff/Fs 0],[0 0]);
sl = tf2ss(hz);
yf = flts(y,sl);

plot(t,y,'-b');
plot(t,yf,'-r');
//---------------------------

Best regards
Anders

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