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Copyright (c) 1995 Rice University - CNRS (France) 1996.
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<refentry xml:id="ffmt" xml:lang="en"
          xmlns="http://docbook.org/ns/docbook"
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          xmlns:db="http://docbook.org/ns/docbook">

  <refnamediv>
    <refname>ffmt</refname>
	<refpurpose>Fast Fourier Mellin Transform</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <title>Calling Sequence</title>
    <synopsis>
      [MELLIN,BETA] = ffmt(X)
      [MELLIN,BETA] = ffmt(X, FMIN, FMAX)
      [MELLIN,BETA] = ffmt(X, FMIN, FMAX, N)
    </synopsis>
  </refsynopsisdiv>

  <refsection>
    <title>Parameters</title>
    <variablelist>
      <varlistentry>
        <term>X :</term>
        <listitem>
          <para>a real vector of size Nx: the signal in time.</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term> FMIN:</term> 
        <listitem>
          <para>
            a positive scalar in ]0 0.5], the normalized lower
            frequency bound in (Hz) of the analyzed signal. When
            unspecified, you have to enter it at the command line from
          the plot of the spectrum. </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term> FMAX :</term> 
        <listitem>
          <para> a positive scalar in ]0 0.5], the normalized upper
          frequency bound (in Hz) of the analyzed signal.  When
          unspecified, you have to enter it at the command line from
          the plot of the spectrum.
          </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>N :</term> 
        <listitem>
          <para>a positive integer: number of analyzed voices.  When
          unspecified, you have to enter it at the command line.</para>
        </listitem>
      </varlistentry>


      <varlistentry>
        <term>MELLIN :</term>
        <listitem>
          <para>a complex row vector of size N: the N-points Mellin transform of signal X.</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>BETA :</term>
        <listitem>
          <para>a real row vector of size N: the N-points Mellin variable.</para>
          <para>The increment between two consecutive elements is constant.</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsection>

  <refsection>
    <title>Description</title>
    <para>
      ffmt computes the Fast Mellin  Transform of signal X.
    </para>
  </refsection>

  <refsection>
    <title>Examples</title>
    <programlisting role="example"><![CDATA[
    sig = altes(128,0.05,0.45);
    [MELLIN,BETA] = ffmt(sig,0.05,0.5,148);
    clf
    subplot(211); plot(sig)
    subplot(212); plot(BETA,real(MELLIN));
    ]]></programlisting>
    <scilab:image><![CDATA[
    sig=altes(128,0.05,0.45);
    [MELLIN,BETA]=ffmt(sig,0.05,0.5,148);
    clf;
    subplot(211); plot(sig)
    subplot(212);plot(BETA,real(MELLIN));
    ]]></scilab:image>
  </refsection>

  <refsection role="see also">
    <title>See also</title>
    <simplelist type="inline">
      <member><link linkend="iffmt">iffmt</link></member>
    </simplelist>
  </refsection>

  <refsection>
    <title>Authors</title>
    <simplelist type="vert">
      <member>H. Nahrstaedt - Aug 2010</member>
      <member>P. Goncalves 9-95 - O. Lemoine, June 1996.</member>
    </simplelist>
  </refsection>
</refentry>
