* Bug #13810 fixed - householder(v, k*v) returned column of %nan. Input parameters...
[scilab.git] / scilab / modules / linear_algebra / help / pt_BR / factorization / givens.xml
1 <?xml version="1.0" encoding="ISO-8859-1"?>
2 <!--
3  * Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
4  * Copyright (C) 2008 - INRIA
5  * 
6  * Copyright (C) 2012 - 2016 - Scilab Enterprises
7  *
8  * This file is hereby licensed under the terms of the GNU GPL v2.0,
9  * pursuant to article 5.3.4 of the CeCILL v.2.1.
10  * This file was originally licensed under the terms of the CeCILL v2.1,
11  * and continues to be available under such terms.
12  * For more information, see the COPYING file which you should have received
13  * along with this program.
14  *
15  -->
16 <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" xmlns:scilab="http://www.scilab.org" xml:id="givens" xml:lang="en">
17     <refnamediv>
18         <refname>givens</refname>
19         <refpurpose>transformação de Givens</refpurpose>
20     </refnamediv>
21     <refsynopsisdiv>
22         <title>Seqüência de Chamamento</title>
23         <synopsis>U=givens(xy)
24             U=givens(x,y)
25             [U,c]=givens(xy)
26             [U,c]=givens(x,y)
27         </synopsis>
28     </refsynopsisdiv>
29     <refsection>
30         <title>Parâmetros</title>
31         <variablelist>
32             <varlistentry>
33                 <term>x,y</term>
34                 <listitem>
35                     <para>dois números reais ou complexos</para>
36                 </listitem>
37             </varlistentry>
38             <varlistentry>
39                 <term>xy</term>
40                 <listitem>
41                     <para>vetor coluna de reais ou complexos de tamanho 2</para>
42                 </listitem>
43             </varlistentry>
44             <varlistentry>
45                 <term>U</term>
46                 <listitem>
47                     <para>matriz 2x2 unitária</para>
48                 </listitem>
49             </varlistentry>
50             <varlistentry>
51                 <term>c</term>
52                 <listitem>
53                     <para>vetor coluna de reais ou complexos de tamanho 2</para>
54                 </listitem>
55             </varlistentry>
56         </variablelist>
57     </refsection>
58     <refsection>
59         <title>Descrição</title>
60         <para>
61             <literal>U= givens(x, y)</literal> ou <literal>U =
62                 givens(xy)
63             </literal>
64             com <literal>xy = [x;y]</literal> retorna uma matriz
65             unitária <literal>2</literal>x<literal>2</literal> <literal>U</literal>
66             tal que:
67         </para>
68         <para>
69             <literal>U*xy=[r;0]=c</literal>.
70         </para>
71         <para>
72             <note>
73                 Note que <literal>givens(x,y)</literal> e
74                 <literal>givens([x;y])</literal> são equivalentes.
75             </note>
76         </para>
77     </refsection>
78     <refsection>
79         <title>Exemplos</title>
80         <programlisting role="example"><![CDATA[ 
81 A=[3,4;5,6];
82 U=givens(A(:,1));
83 U*A
84  ]]></programlisting>
85     </refsection>
86     <refsection role="see also">
87         <title>Ver Também</title>
88         <simplelist type="inline">
89             <member>
90                 <link linkend="qr">qr</link>
91             </member>
92         </simplelist>
93     </refsection>
94 </refentry>