← Back to branch summary

~ubuntu-branches/ubuntu/raring/scilab/raring-proposed

« back to all changes in this revision

Viewing changes to modules/signal_processing/help/en_US/iir.xml

  • Committer: Package Import Robot
  • Author(s): Sylvestre Ledru
  • Date: 2012-08-30 14:42:38 UTC
  • mfrom: (1.4.7)
  • Revision ID: package-import@ubuntu.com-20120830144238-c1y2og7dbm7m9nig
Tags: 5.4.0-beta-3-1~exp1
* New upstream release
* Update the scirenderer dep
* Get ride of libjhdf5-java dependency

Show diffs side-by-side

added added

removed removed

Lines of Context:
modules/signal_processing/help/en_US/iir.xml
1
 
<?xml version="1.0" encoding="UTF-8"?>
2
 
<refentry xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:svg="http://www.w3.org/2000/svg" xmlns:ns4="http://www.w3.org/1999/xhtml" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:db="http://docbook.org/ns/docbook" version="5.0-subset Scilab" xml:id="iir" xml:lang="en">
3
 
  <refnamediv>
4
 
    <refname>iir</refname>
5
 
    <refpurpose>iir digital filter</refpurpose>
6
 
  </refnamediv>
7
 
  <refsynopsisdiv>
8
 
    <title>Calling Sequence</title>
9
 
    <synopsis>
10
 
      hz=iir(n,ftype,fdesign,frq,delta)
11
 
      [p,z,g]=iir(n,ftype,fdesign,frq,delta)
12
 
    </synopsis>
13
 
  </refsynopsisdiv>
14
 
  <refsection>
15
 
    <title>Arguments</title>
16
 
    <variablelist>
17
 
      <varlistentry>
18
 
        <term>n</term>
19
 
        <listitem>
20
 
          <para>positive number witn inteher value, the filter order.</para>
21
 
        </listitem>
22
 
      </varlistentry>
23
 
      <varlistentry>
24
 
        <term>ftype</term>
25
 
        <listitem>
26
 
          <para>string specifying the filter type, the possible values are:
27
 
            <literal>'lp'</literal> for low-pass,<literal>'hp'</literal> for
28
 
            high pass,<literal>'bp'</literal> for band pass and
29
 
            <literal>'sb'</literal> for stop band.
30
 
          </para>
31
 
        </listitem>
32
 
      </varlistentry>
33
 
      <varlistentry>
34
 
        <term>fdesign</term>
35
 
        <listitem>
36
 
          <para>string specifying the analog filter design, the
37
 
            possible values are: <literal>'butt'</literal>,
38
 
            <literal>'cheb1'</literal>, <literal>'cheb2'</literal> and
39
 
            <literal>'ellip'</literal>
40
 
          </para>
41
 
        </listitem>
42
 
      </varlistentry>
43
 
      <varlistentry>
44
 
        <term>frq</term>
45
 
        <listitem>
46
 
          <para>2-vector of discrete cut-off frequencies (i.e.,
47
 
            <literal>0&lt;frq&lt;.5</literal>). For <literal>'lp'</literal> and
48
 
            <literal>'hp'</literal> filters only <literal>frq(1)</literal> is
49
 
            used. For <literal>'bp'</literal> and <literal>'sb'</literal> filters
50
 
            <literal>frq(1)</literal> is the lower cut-off frequency and
51
 
            <literal>frq(2)</literal> is the upper cut-off frequency
52
 
          </para>
53
 
        </listitem>
54
 
      </varlistentry>
55
 
      <varlistentry>
56
 
        <term>delta</term>
57
 
        <listitem>
58
 
          <para>
59
 
            2-vector of error values for <literal>cheb1</literal>,
60
 
            <literal>cheb2</literal>, and <literal>ellip</literal> filters where
61
 
            only <literal>delta(1)</literal> is used for
62
 
            <literal>cheb1</literal> case, only <literal>delta(2)</literal> is
63
 
            used for <literal>cheb2</literal> case, and
64
 
            <literal>delta(1)</literal> and <literal>delta(2)</literal> are both
65
 
            used for <literal>ellip</literal> case.
66
 
            <literal>0&lt;delta(1),delta(2)&lt;1</literal>
67
 
          </para>
68
 
          <itemizedlist>
69
 
            <listitem>
70
 
              <para>
71
 
                for <literal>cheb1</literal> filters
72
 
                <literal>1-delta(1)&lt;ripple&lt;1</literal> in passband
73
 
              </para>
74
 
            </listitem>
75
 
            <listitem>
76
 
              <para>
77
 
                for <literal>cheb2</literal> filters
78
 
                <literal>0&lt;ripple&lt;delta(2)</literal> in stopband
79
 
              </para>
80
 
            </listitem>
81
 
            <listitem>
82
 
              <para>
83
 
                for <literal>ellip</literal> filters
84
 
                <literal>1-delta(1)&lt;ripple&lt;1</literal> in passband and
85
 
                <literal>0&lt;ripple&lt;delta(2)</literal> in stopband
86
 
              </para>
87
 
            </listitem>
88
 
          </itemizedlist>
89
 
        </listitem>
90
 
      </varlistentry>
91
 
      <varlistentry>
92
 
        <term>hz</term>
93
 
        <listitem>
94
 
          <para>a single input single output discrete transfer function, the low pass filter</para>
95
 
        </listitem>
96
 
      </varlistentry>
97
 
      <varlistentry>
98
 
        <term>p</term>
99
 
        <listitem>
100
 
          <para>vector of transformed filter zeros.</para>
101
 
        </listitem>
102
 
      </varlistentry>
103
 
      <varlistentry>
104
 
        <term>z</term>
105
 
        <listitem>
106
 
          <para>vector of transformed filter poles.</para>
107
 
        </listitem>
108
 
      </varlistentry>
109
 
      <varlistentry>
110
 
        <term>g </term>
111
 
        <listitem>
112
 
          <para>a scalar: transformed filter gain.</para>
113
 
        </listitem>
114
 
      </varlistentry>
115
 
    </variablelist>
116
 
  </refsection>
117
 
  <refsection>
118
 
    <title>Description</title>
119
 
    <para>
120
 
      function which designs an iir digital filter using <link linkend="analpf">analog filter</link> designs and <link linkend="bilt">bilinear transformation</link> .
121
 
    </para>
122
 
  </refsection>
123
 
  <refsection>
124
 
    <title>Examples</title>
125
 
    <programlisting role="example"><![CDATA[ 
126
 
hz=iir(3,'bp','ellip',[.15 .25],[.08 .03]);
127
 
[hzm,fr]=frmag(hz,256);
128
 
plot2d(fr',hzm')
129
 
xtitle('Discrete IIR filter band pass  0.15 < fr < 0.25 ',' ',' ');
130
 
q=poly(0,'q');     //to express the result in terms of the delay operator q=z^-1
131
 
hzd=horner(hz,1/q) 
132
 
 
133
 
//Poles Zeros Gain filter representation
134
 
[p,z,g]=iir(3,'bp','ellip',[.15 .25],[.08 .03]);
135
 
g*poly(z,'z')/poly(p,'z')
136
 
 ]]></programlisting>
137
 
  </refsection>
138
 
  <refsection role="see also">
139
 
    <title>See Also</title>
140
 
    <simplelist type="inline">
141
 
      <member>
142
 
        <link linkend="eqfir">eqfir</link>
143
 
      </member>
144
 
      <member>
145
 
        <link linkend="eqiir">eqiir</link>
146
 
      </member>
147
 
      <member>
148
 
        <link linkend="analpf">analpf</link>
149
 
      </member>
150
 
      <member>
151
 
        <link linkend="bilt">bilt</link>
152
 
      </member>
153
 
    </simplelist>
154
 
  </refsection>
155
 
</refentry>