<?xml version="1.0" encoding="UTF-8"?>
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 * Copyright (C) 2012 - 2016 - Scilab Enterprises
 *
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 * pursuant to article 5.3.4 of the CeCILL v.2.1.
 * This file was originally licensed under the terms of the CeCILL v2.1,
 * and continues to be available under such terms.
 * For more information, see the COPYING file which you should have received
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<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="dscr">
    <refnamediv>
        <refname>dscr</refname>
        <refpurpose>discretization of linear system</refpurpose>
    </refnamediv>
    <refsynopsisdiv>
        <title>Syntax</title>
        <synopsis>
            [sld, r] = dscr(sl, dt)
            [sld, r] = dscr(sl, dt, m)
        </synopsis>
    </refsynopsisdiv>
    <refsection>
        <title>Arguments</title>
        <variablelist>
            <varlistentry>
                <term>sl</term>
                <listitem>
                    <para>
                        <literal>syslin</literal> list containing <literal>[A,B,C,D]</literal>.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>dt</term>
                <listitem>
                    <para>real number, sampling period</para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>m</term>
                <listitem>
                    <para>covariance of the input noise (continuous time)(default value=0)</para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>r</term>
                <listitem>
                    <para>
                        covariance of the output noise (discrete time) given if <literal>m</literal> is  given as input
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>sld</term>
                <listitem>
                    <para>
                        sampled (discrete-time) linear system, <literal>syslin</literal> list
                    </para>
                </listitem>
            </varlistentry>
        </variablelist>
    </refsection>
    <refsection>
        <title>Description</title>
        <para>
            Discretization of linear system. <literal>sl</literal> is a continuous-time system:
        </para>
        <para>
            <literal>dx/dt=A*x+B*u (+ noise)</literal>.
        </para>
        <para>
            <literal>sld</literal> is the discrete-time system obtained by
            sampling <literal>sl</literal> with the sampling period <literal>dt</literal>.
        </para>
    </refsection>
    <refsection>
        <title>Examples</title>
        <programlisting role="example"><![CDATA[
s=poly(0,'s');
Sys=syslin('c',[1,1/(s+1);2*s/(s^2+2),1/s])
ss2tf(dscr(tf2ss(Sys),0.1))
 ]]></programlisting>
    </refsection>
    <refsection role="see also">
        <title>See also</title>
        <simplelist type="inline">
            <member>
                <link linkend="syslin">syslin</link>
            </member>
            <member>
                <link linkend="flts">flts</link>
            </member>
            <member>
                <link linkend="dsimul">dsimul</link>
            </member>
        </simplelist>
    </refsection>
</refentry>
