Typo fixes
[scilab.git] / scilab / modules / signal_processing / help / en_US / convol2d.xml
1 <?xml version="1.0" encoding="UTF-8"?>
2 <!--
3  * Add some comments about XML file
4 -->
5 <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_US" xml:id="convol2d">
6     <refnamediv>
7         <refname>convol2d</refname>
8         <refpurpose>discrete 2-D convolution, using fft. </refpurpose>
9     </refnamediv>
10     <refsynopsisdiv>
11         <title>Syntax</title>
12         <synopsis>C = convol2d(A,B)</synopsis>
13     </refsynopsisdiv>
14     <refsection>
15         <title>Parameters</title>
16         <variablelist>
17             <varlistentry>
18                 <term>A</term>
19                 <listitem>
20                     <para>
21                         a real or complex 2-D array.
22                     </para>
23                 </listitem>
24             </varlistentry>
25             <varlistentry>
26                 <term>B</term>
27                 <listitem>
28                     <para>
29                         a real or complex 2-D array.
30                     </para>
31                 </listitem>
32             </varlistentry>
33             <varlistentry>
34                 <term>C</term>
35                 <listitem>
36                     <para>
37                         a real or complex 2-D array.
38                     </para>
39                 </listitem>
40             </varlistentry>
41         </variablelist>
42     </refsection>
43     <refsection>
44         <title>Description</title>
45         <para>
46             <literal>convol2d</literal> uses fft to compute the full
47             two-dimensional discrete convolution. The
48             dimensions of the result<literal>C</literal> are given by
49             <literal>size(A)+size(B)+1</literal>. The indices of the
50             center element of <literal>B</literal> are defined as
51             <literal>floor((size(B)+1)/2)</literal>.
52         </para>
53     </refsection>
54     <refsection>
55         <title>Examples</title>
56         <programlisting role="example"><![CDATA[
57     s = [1 2 1; 0 0 0; -1 -2 -1];//Sobel horizontal edge kernel
58     A = zeros(10,10);A(3:7,3:7) = 1;
59     convol2d(s,A);
60     ]]></programlisting>
61     </refsection>
62     <refsection>
63         <title>See Also</title>
64         <simplelist type="inline">
65             <member>
66                 <link linkend="conv2">conv2</link>
67             </member>
68             <member>
69                 <link linkend="convol">convol</link>
70             </member>
71         </simplelist>
72     </refsection>
73     <refsection>
74         <title>Used Functions</title>
75         <para>
76             The  <literal>convol2d</literal> function is based on the <link linkend="fft">fft</link> builtin.
77         </para>
78     </refsection>
79     <refsection>
80         <title>History</title>
81         <revhistory>
82             <revision>
83                 <revnumber>5.4.0</revnumber>
84                 <revremark>Function convol2d introduced.</revremark>
85             </revision>
86         </revhistory>
87     </refsection>
88 </refentry>