<?xml version="1.0" encoding="UTF-8"?>
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Copyright (c) 1996 by CNRS (France)
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<refentry xml:id="tfristft" xml:lang="en"
          xmlns="http://docbook.org/ns/docbook"
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          xmlns:svg="http://www.w3.org/2000/svg"
          xmlns:scilab="http://www.scilab.org"
          xmlns:ns3="http://www.w3.org/1999/xhtml"
          xmlns:mml="http://www.w3.org/1998/Math/MathML"
          xmlns:db="http://docbook.org/ns/docbook">

  <refnamediv>
    <refname>tfristft</refname>
	<refpurpose>Inverse Short time Fourier transform</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <title>Calling Sequence</title>
    <synopsis>
      [X,T] = tfristft(tfr, T, H)
      [X,T] = tfristft(tfr, T, H, TRACE)
    </synopsis>
  </refsynopsisdiv>

  <refsection>
    <title>Parameters</title>
    <variablelist>
      <varlistentry>
        <term>tfr     :</term>
        <listitem>
          <para>>a N by M complex matrix: the time-frequency representation.</para>
        </listitem>
      </varlistentry>
   
      <varlistentry>
        <term>	T:</term>
        <listitem>
          <para>a vector with integer values and increments between
          elements equal to 1: the time instant(s)(default :
          1:length(X)).</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>	H     :</term>
        <listitem>
          <para>a real vector with odd size: the frequency smoothing window, H being normalized so as to be of unit energy.</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>	TRACE :</term>
        <listitem>
          <para> if nonzero of %t, the progression of the algorithm is shown      (default : %f).</para>
        </listitem>
      </varlistentry>
   <varlistentry>
        <term>	X     :</term>
        <listitem>
          <para>a column vector of size length(t): the signal with the specified time frequency representation.</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsection>

  <refsection>
    <title>Description</title>
    <para>
      tfristft computes the inverse short-time Fourier transform of a
      discrete-time signal X. This function may be used for
      time-frequency synthesis of signals.
    </para>
  </refsection>

  <refsection>
    <title>Examples</title>
    <programlisting role="example"><![CDATA[
    t = 200+(-128:127); 
    sig = [fmconst(200,0.2) ; fmconst(200,0.4)];
    h = window("hm",57); 
    tfr = tfrstft(sig,t,256,h);
    sigsyn = tfristft(tfr,t,h);
    plot(t',abs(sigsyn-sig(t)))
    ]]></programlisting>
    <scilab:image><![CDATA[
    t=200+(-128:127); 
    sig=[fmconst(200,0.2);fmconst(200,0.4)];
    h=window("hm",57); 
    tfr=tfrstft(sig,t,256,h);
    sigsyn=tfristft(tfr,t,h);
    plot(t',abs(sigsyn-sig(t)))
    ]]></scilab:image>
  </refsection>

  <refsection>
    <title>Authors</title>
    <simplelist type="vert">
      <member>H. Nahrstaedt - Aug 2010</member>
      <member>	F. Auger, November 1996.</member>
    </simplelist>
  </refsection>
</refentry>
