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<?xml version="1.0" encoding="UTF-8"?>

<!--
 *
 * This help file was generated from cheby2.sci using help_from_sci().
 *
 -->

<refentry version="5.0-subset Scilab" xml:id="cheby2" 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>cheby2</refname>
    <refpurpose>This function generates a Chebyshev type II filter with rs dB of stopband attenuation.</refpurpose>
  </refnamediv>


<refsynopsisdiv>
   <title>Calling Sequence</title>
   <synopsis>
   [a, b] = cheby2 (n, rs, wc)
   [a, b] = cheby2 (n, rs, wc, "high")
   [a, b] = cheby2 (n, rs, [wl, wh])
   [a, b] = cheby2 (n, rs, [wl, wh], "stop")
   [a, b, c] = cheby2 (…)
   [a, b, c, d] = cheby2 (…)
   […] = cheby2 (…, "s")
   </synopsis>
</refsynopsisdiv>

<refsection>
   <title>Parameters</title>
   <variablelist>
   <varlistentry><term>n:</term>
      <listitem><para> positive integer value</para></listitem></varlistentry>
   <varlistentry><term>rp:</term>
      <listitem><para> non negative scalar value</para></listitem></varlistentry>
   <varlistentry><term>w:</term>
      <listitem><para> vector, all elements must be in the range [0,1]</para></listitem></varlistentry>
   </variablelist>
</refsection>

<refsection>
   <title>Description</title>
   <para>
This is an Octave function.
This function generates a Chebyshev type II filter with rs dB of stopband attenuation.
The fourth parameter takes in high or low, default value is low. The cutoff is pi*Wc radians.
[b, a] = cheby2(n, Rp, [Wl, Wh]) indicates a band pass filter with edges pi*Wl and pi*Wh radians.
[b, a] = cheby2(n, Rp, [Wl, Wh], ’stop’) indicates a band reject filter with edges pi*Wl and pi*Wh radians.
[z, p, g] = cheby2(...) returns filter as zero-pole-gain rather than coefficients of the numerator and denominator polynomials.
[...] = cheby2(...,’s’) returns a Laplace space filter, w can be larger than 1.
[a,b,c,d] = cheby2(...) returns state-space matrices.
</para>
</refsection>

<refsection>
   <title>Examples</title>
   <programlisting role="example"><![CDATA[
[a,b,c]=cheby2(2,5,0.7,"high")
a =
-0.31645 - 0.94861i  -0.31645 + 0.94861i
b =
-0.39388 + 0.53138i  -0.39388 - 0.53138i
c =  0.47528
   ]]></programlisting>
</refsection>
</refentry>