<?xml version="1.0" encoding="UTF-8"?> <!-- * * This help file was generated from pei_tseng_notch.sci using help_from_sci(). * --> <refentry version="5.0-subset Scilab" xml:id="pei_tseng_notch" xml:lang="en" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:svg="http://www.w3.org/2000/svg" xmlns:ns3="http://www.w3.org/1999/xhtml" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:scilab="http://www.scilab.org" xmlns:db="http://docbook.org/ns/docbook"> <refnamediv> <refname>pei_tseng_notch</refname> <refpurpose></refpurpose> </refnamediv> <refsynopsisdiv> <title>Calling Sequence</title> <synopsis> [b, a] = pei_tseng_notch (frequencies, bandwidths) b = pei_tseng_notch (frequencies, bandwidths) </synopsis> </refsynopsisdiv> <refsection> <title>Parameters</title> <variablelist> <varlistentry><term>frequencies:</term> <listitem><para> filter frequencies</para></listitem></varlistentry> <varlistentry><term>bandwidths:</term> <listitem><para> bandwidths to be used with filter</para></listitem></varlistentry> </variablelist> </refsection> <refsection> <title>Description</title> <para> This is an Octave function. It return coefficients for an IIR notch-filter with one or more filter frequencies and according bandwidths. The filter is based on a all pass filter that performs phasereversal at filter frequencies. This leads to removal of those frequencies of the original and phase-distorted signal. </para> </refsection> <refsection> <title>Examples</title> <programlisting role="example"><![CDATA[ sf = 800; sf2 = sf/2; data=[[1;zeros(sf-1,1)],sinetone(49,sf,1,1),sinetone(50,sf,1,1),sinetone(51,sf,1,1)]; [b,a]=pei_tseng_notch ( 50 / sf2, 2/sf2 ) b = 0.99213 -1.83322 0.99213 a = 1.00000 -1.83322 0.98426 ]]></programlisting> </refsection> </refentry>