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Viewing changes to modules/differential_equations/help/en_US/diff.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

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modules/differential_equations/help/en_US/diff.xml
 
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<?xml version="1.0" encoding="UTF-8"?>
 
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<!--
 
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 * Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
 
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 * Copyright (C) 2008 - INRIA
 
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 * 
 
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 * This file must be used under the terms of the CeCILL.
 
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 * This source file is licensed as described in the file COPYING, which
 
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 * you should have received as part of this distribution.  The terms
 
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 * are also available at    
 
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 * http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
 
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 *
 
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 -->
 
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<refentry xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:svg="http://www.w3.org/2000/svg" xmlns:ns5="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="diff" xml:lang="en">
 
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    <refnamediv>
 
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        <refname>diff</refname>
 
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        <refpurpose>Difference and discrete derivative</refpurpose>
 
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    </refnamediv>
 
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    <refsynopsisdiv>
 
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        <title>Calling Sequence</title>
 
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        <synopsis>y=diff(x)
 
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            y=diff(x [,n [,dim]])
 
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        </synopsis>
 
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    </refsynopsisdiv>
 
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    <refsection>
 
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        <title>Arguments</title>
 
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        <variablelist>
 
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            <varlistentry>
 
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                <term>x</term>
 
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                <listitem>
 
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                    <para>vector or matrix (real, complex, sparse or polynomial)</para>
 
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                </listitem>
 
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            </varlistentry>
 
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            <varlistentry>
 
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                <term>n</term>
 
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                <listitem>
 
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                    <para>integer the order of differentiation</para>
 
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                </listitem>
 
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            </varlistentry>
 
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            <varlistentry>
 
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                <term>dim</term>
 
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                <listitem>
 
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                    <para>integer or character string with values "r","c" and "*"</para>
 
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                </listitem>
 
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            </varlistentry>
 
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            <varlistentry>
 
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                <term>y</term>
 
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                <listitem>
 
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                    <para>scalar or vector/matrix</para>
 
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                </listitem>
 
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            </varlistentry>
 
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        </variablelist>
 
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    </refsection>
 
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    <refsection>
 
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        <title>Description</title>
 
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        <para>
 
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            <literal>y=diff(x)</literal> compute the difference function
 
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            <literal>y=x(2:$)-x(1:$-1)</literal>
 
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        </para>
 
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        <para>
 
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            <literal>diff(x,n,dim)</literal> is the <literal>n</literal>th
 
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            difference function along dimension <literal>dim</literal>.
 
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        </para>
 
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        <para>
 
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            <literal>diff(x,n,"*")</literal> is equivalent to
 
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            <literal>diff(x(:),n)</literal>.
 
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        </para>
 
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        <para>
 
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            Default value for <literal>n</literal> is 1. Default value for
 
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            <literal>dim</literal> is <literal>"*"</literal>.
 
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        </para>
 
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        <para>
 
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            <literal>dim='r'</literal> is equivalent to <literal>dim=1</literal>
 
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            and <literal>dim='c'</literal> is equivalent to
 
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            <literal>dim=2</literal>.
 
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        </para>
 
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    </refsection>
 
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    <refsection>
 
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        <title>Examples</title>
 
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        <programlisting role="example"><![CDATA[ 
 
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v=(1:8)^3;
 
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diff(v)
 
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diff(v,3)
 
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A=[(1:8)^2
 
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   (1:8)^3
 
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   (1:8)^4];
 
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diff(A,3,2)
 
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//approximate differentiation
 
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step=0.001
 
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t=0:step:10;
 
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y=sin(t);
 
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dy=diff(sin(t))/step; //approximate differentiation of sine function
 
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norm(dy-cos(t(1:$-1)),%inf)
 
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 ]]></programlisting>
 
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    </refsection>
 
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</refentry>