<?xml version="1.0" encoding="UTF-8"?>
<!--
 * Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
 * Copyright (C) 2000 - 2016 - INRIA - Serge Steer <serge.steer@inria.fr>
 * Copyright (C) 2012 - 2016 - Scilab Enterprises
 *
 * This file is hereby licensed under the terms of the GNU GPL v2.0,
 * 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
 * along with this program.
 *
 -->
<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="krac2">
    <refnamediv>
        <refname>krac2</refname>
        <refpurpose>continuous SISO system limit feedback gain</refpurpose>
    </refnamediv>
    <refsynopsisdiv>
        <title>Syntax</title>
        <synopsis>g = krac2(sys)</synopsis>
    </refsynopsisdiv>
    <refsection>
        <title>Arguments</title>
        <variablelist>
            <varlistentry>
                <term>sys</term>
                <listitem>
                    A SISO linear dynamical system, in state space,
                    transfer function or zpk representations, in
                    continuous or discrete time.
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>g</term>
                <listitem>
                    <para>constant</para>
                </listitem>
            </varlistentry>
        </variablelist>
    </refsection>
    <refsection>
        <title>Description</title>
        <para>
            <literal>krac2(sys)</literal> computes the gains <literal>g</literal> such that the system
            <literal>sys</literal> feedback by g (<literal>sys/.g</literal>) has  2 real equal poles.
        </para>
    </refsection>
    <refsection>
        <title>Examples</title>
        <programlisting role="example"><![CDATA[
h = syslin('c', 352*poly(-5,'s') / poly([0,0,2000,200,25,1],'s','c'));
clf
evans(h,100)
g = krac2(h)
hf1 = h/.g(1); roots(hf1.den)
hf2 = h/.g(2); roots(hf2.den)
 ]]></programlisting>
    </refsection>
    <refsection role="see also">
        <title>See also</title>
        <simplelist type="inline">
            <member>
                <link linkend="evans">evans</link>
            </member>
            <member>
                <link linkend="kpure">kpure</link>
            </member>
        </simplelist>
    </refsection>
    <refsection role="history">
        <title>History</title>
        <revhistory>
            <revision>
                <revnumber>6.0</revnumber>
                <revdescription>
                    <para>handling zpk representation</para>
                </revdescription>
            </revision>
        </revhistory>
    </refsection>

</refentry>
