Typo fixes
[scilab.git] / scilab / modules / signal_processing / help / en_US / cepstrum.xml
1 <?xml version="1.0" encoding="UTF-8"?>
2 <refentry xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:svg="http://www.w3.org/2000/svg" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:db="http://docbook.org/ns/docbook" xmlns:scilab="http://www.scilab.org" xml:lang="en" xml:id="cepstrum">
3     <refnamediv>
4         <refname>cepstrum</refname>
5         <refpurpose>cepstrum calculation</refpurpose>
6     </refnamediv>
7     <refsynopsisdiv>
8         <title>Syntax</title>
9         <synopsis>fresp = cepstrum(w,mag)</synopsis>
10     </refsynopsisdiv>
11     <refsection>
12         <title>Arguments</title>
13         <variablelist>
14             <varlistentry>
15                 <term>w</term>
16                 <listitem>
17                     <para>positive real vector of frequencies (rad/sec)</para>
18                 </listitem>
19             </varlistentry>
20             <varlistentry>
21                 <term>mag</term>
22                 <listitem>
23                     <para>
24                         real vector of magnitudes (same size as <literal>w</literal>)
25                     </para>
26                 </listitem>
27             </varlistentry>
28             <varlistentry>
29                 <term>fresp</term>
30                 <listitem>
31                     <para>complex vector</para>
32                 </listitem>
33             </varlistentry>
34         </variablelist>
35     </refsection>
36     <refsection>
37         <title>Description</title>
38         <para>
39             <literal>fresp = cepstrum(w,mag)</literal> returns a frequency response <literal>fresp(i)</literal>
40             whose magnitude at frequency <literal>w(i)</literal> equals <literal>mag(i)</literal>  and such
41             that the phase of <literal>freq</literal> corresponds to a stable and minimum phase
42             system. <literal>w</literal> needs not to be sorted, but  minimal entry should not be
43             close to zero and all the entries of <literal>w</literal> should be different.
44         </para>
45     </refsection>
46     <refsection>
47         <title>Examples</title>
48         <programlisting role="example"><![CDATA[ 
49 w=0.1:0.1:5;mag=1+abs(sin(w));
50 fresp=cepstrum(w,mag);
51 plot2d([w',w'],[mag(:),abs(fresp)])
52  ]]></programlisting>
53         <scilab:image>
54             w=0.1:0.1:5;mag=1+abs(sin(w));
55             fresp=cepstrum(w,mag);
56             plot2d([w',w'],[mag(:),abs(fresp)])
57         </scilab:image>
58     </refsection>
59     <refsection role="see also">
60         <title>See Also</title>
61         <simplelist type="inline">
62             <member>
63                 <link linkend="frfit">frfit</link>
64             </member>
65         </simplelist>
66     </refsection>
67 </refentry>