<?xml version="1.0" encoding="UTF-8"?>
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Copyright (c) 1996 by CNRS (France).
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<refentry version="5.0-subset Scilab" xml:id="holder" xml:lang="en"
          xmlns="http://docbook.org/ns/docbook"
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          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>holder</refname><refpurpose>Estimate the Holder exponent through an affine TFR.</refpurpose>
  </refnamediv>



  <refsynopsisdiv>
    <title>Calling Sequence</title>
    <synopsis>
      H=holder(TFR,F)
      H=holder(TFR,F,N1)
      H=holder(TFR,F,N1,N2)
      H=holder(TFR,F,N1,N2,T)
      H=holder(...'plot')
    </synopsis>
  </refsynopsisdiv>

  <refsection>
    <title>Parameters</title>
    <variablelist>
      <varlistentry>

        <term>	TFR :</term>
        <listitem>
          <para> a M by N array of doubles: the affine time-frequency representation.</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>	F   :</term>
        <listitem><para>a real vector of size M with elements in ]0 0.5]: the frequency values of the spectral analysis.</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>	N1  :</term>
        <listitem>
          <para>an integer value  in [1 M]: the indice of the  minimum frequency for the linear regression.    (default : 1).</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>	N2  :</term>
        <listitem>
          <para>an integer value  in [1 M]: the  indice of the  maximum frequency for the linear regression.   (default : M).</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>	T :</term>
        <listitem>
          <para>a vector of integer values in [1 N]: the time vector. If T is
          omitted, the function returns the global estimate of the
          Holder exponent. Otherwise, it returns the local estimates
          H(T) at the instants specified in T.</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>	H :</term>
        <listitem>
          <para>a real scalar if T omitted or a real column vector: the Holder estimate(s).</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsection>

  <refsection>
    <title>Description</title>
    <para>
      holder estimates the Holder exponent of a function through an affine time-frequency representation of it,
      and plots the frequency marginal and the regression line.
    </para>
  </refsection>

  <refsection>
    <title>Examples</title>
    <programlisting role="example"><![CDATA[
    S=altes(128); 
    [TFR,T,F]=tfrscalo(S,1:128,8,0.01,0.35,128);
    H=holder(TFR,F,1,length(F),1:128);
    clf;plot(H)
    ]]></programlisting>
    <scilab:image><![CDATA[
    S=altes(128); 
    [TFR,T,F]=tfrscalo(S,1:128,8,0.01,0.35,128);
    H=holder(TFR,F,1,length(F),1:128);
    clf;plot(H)
    ]]></scilab:image>
  </refsection>

  <refsection>
    <title>Authors</title>
    <simplelist type="vert">
      <member>H. Nahrstaedt - Aug 2010</member>
      <member>	P. Goncalves, October 1995</member>
      <member>	Copyright (c) 1995 Rice University</member>
    </simplelist>
  </refsection>
</refentry>
