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<?xml version="1.0" encoding="UTF-8"?>
<!--
*
* This help file was generated from dctmtx.sci using help_from_sci().
*
-->
<refentry version="5.0-subset Scilab" xml:id="dctmtx" 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>dctmtx</refname>
<refpurpose></refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Calling Sequence</title>
<synopsis>
[y]=dctmtx(n)
</synopsis>
</refsynopsisdiv>
<refsection>
<title>Parameters</title>
<variablelist>
<varlistentry><term>n:</term>
<listitem><para> Real scalar integer greater than or equal to 1</para></listitem></varlistentry>
</variablelist>
</refsection>
<refsection>
<title>Description</title>
<para>
This is an Octave function
dctmtx(n) returns a Discrete cosine transform matrix of order n-by-n. It is useful for jpeg image compression. D*A is the DCT of the columns of A and D'*A is the inverse DCT of the columns of A (when A is n-by-n).
</para>
</refsection>
<refsection>
<title>Examples</title>
<programlisting role="example"><![CDATA[
1. dctmtx(2)
ans = [0.70711 0.70711; 0.70711 -0.70711]
2. dctmtx(3)
ans = [5.7735e-01 5.7735e-01 5.7735e-01;
7.0711e-01 4.9996e-17 -7.0711e-01;
4.0825e-01 -8.1650e-01 4.0825e-01]
]]></programlisting>
</refsection>
</refentry>
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