scilab/modules/cacsd/help/en_US/plot_display/nicholschart.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
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   9  * are also available at
  10  * http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
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  13 <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="nicholschart">
  14     <refnamediv>
  15         <refname>nicholschart</refname>
  16         <refpurpose>Nichols chart</refpurpose>
  17     </refnamediv>
  18     <refsynopsisdiv>
  19         <title>Calling Sequence</title>
  20         <synopsis>nicholschart([modules] [,args] [,colors])</synopsis>
  21         <synopsis/>
  22     </refsynopsisdiv>
  23     <refsection>
  24         <title>Arguments</title>
  25         <variablelist>
  26             <varlistentry>
  27                 <term>modules</term>
  28                 <listitem>
  29                     <para>real vector ( modules (in dB))</para>
  30                 </listitem>
  31             </varlistentry>
  32             <varlistentry>
  33                 <term>args</term>
  34                 <listitem>
  35                     <para>real vector (phases (in degree))</para>
  36                 </listitem>
  37             </varlistentry>
  38             <varlistentry>
  39                 <term>colorss</term>
  40                 <listitem>
  41                     <para>a scalar or a vector, the color indices for isogain and iso phase curves</para>
  42                 </listitem>
  43             </varlistentry>
  44         </variablelist>
  45     </refsection>
  46     <refsection>
  47         <title>Description</title>
  48         <para> plot the Nichols'chart: iso-module and iso-argument  contours of
  49             <literal>y/(1+y)</literal> in <literal>y</literal> phase/gain plane
  50         </para>
  51         <para>
  52             <literal>nicholschart</literal> may be used in cunjunction with
  53             <link linkend="black">black</link>.
  54         </para>
  55         <para>
  56             The default values for <literal>modules</literal> and
  57             <literal>args</literal> are respectively :
  58         </para>
  59         <para>
  60             <literal>[-12 -8 -6 -5 -4 -3 -2 -1.4 -1 -.5 0.25 0.5 0.7 1 1.4 2 2.3 3 4 5 6 8 12]</literal>
  61         </para>
  62         <para>
  63             <literal>[-(1:10) , -(20:10:160)]</literal>
  64         </para>
  65     </refsection>
  66     <refsection>
  67         <title>Examples</title>
  68         <programlisting role="example"><![CDATA[
  69     //Nichols chart
  70     clf()
  71     nicholschart(modules=[-6 -3 -1 1 3 6], args=[-1 -20 20 40 80 160 180]);
  72     ]]></programlisting>
  73         <para>
  74             <scilab:image localized="true">
  75                 nicholschart(modules=[-6 -3 -1 1 3 6], args=[-1 -20 20 40 80 160 180]);
  76             </scilab:image>
  77         </para>
  78         <programlisting role="example"><![CDATA[
  79     //Black diagram with Nichols chart as a grid
  80     s=poly(0,'s');
  81     Plant=syslin('c',16000/((s+1)*(s+10)*(s+100)));
  82     //two degree of freedom PID
  83     tau=0.2;xsi=1.2;
  84     PID=syslin('c',(1/(2*xsi*tau*s))*(1+2*xsi*tau*s+tau^2*s^2));
  85     clf();
  86     black([Plant;Plant*PID ],0.01,100,["Plant";"Plant and PID corrector"]);
  87     //move the caption in the lower rigth corner
  88     ax=gca();Leg=ax.children(1);
  89     Leg.legend_location="in_lower_right";
  90     nicholschart(colors=color('light gray')*[1 1])
  91     ]]></programlisting>
  92         <para>
  93             <scilab:image localized="true">
  94                 s=poly(0,'s');
  95                 Plant=syslin('c',16000/((s+1)*(s+10)*(s+100)));
  96                 //two degree of freedom PID
  97                 tau=0.2;xsi=1.2;
  98                 PID=syslin('c',(1/(2*xsi*tau*s))*(1+2*xsi*tau*s+tau^2*s^2));
  99                 clf();
 100                 black([Plant;Plant*PID ],0.01,100,["Plant";"Plant and PID corrector"]);
 101                 //move the caption in the lower rigth corner
 102                 ax=gca();Leg=ax.children(1);
 103                 Leg.legend_location="in_lower_right";
 104                 nicholschart(colors=color('light gray')*[1 1])
 105             </scilab:image>
 106         </para>
 107     </refsection>
 108     <refsection role="see also">
 109         <title>See Also</title>
 110         <simplelist type="inline">
 111             <member>
 112                 <link linkend="black">black</link>
 113             </member>
 114             <member>
 115                 <link linkend="nyquist">nyquist</link>
 116             </member>
 117             <member>
 118                 <link linkend="hallchart">hallchart</link>
 119             </member>
 120         </simplelist>
 121     </refsection>
 122 </refentry>