* Bug #13810 fixed - householder(v, k*v) returned column of %nan. Input parameters...
[scilab.git] / scilab / modules / linear_algebra / help / en_US / factorization / sqroot.xml
1 <?xml version="1.0" encoding="UTF-8"?>
2 <!--
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12  * For more information, see the COPYING file which you should have received
13  * along with this program.
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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:mml="http://www.w3.org/1998/Math/MathML" xmlns:db="http://docbook.org/ns/docbook" xmlns:scilab="http://www.scilab.org" xml:lang="en" xml:id="sqroot">
17     <refnamediv>
18         <refname>sqroot</refname>
19         <refpurpose>W*W' hermitian factorization</refpurpose>
20     </refnamediv>
21     <refsynopsisdiv>
22         <title>Calling Sequence</title>
23         <synopsis>sqroot(X)</synopsis>
24     </refsynopsisdiv>
25     <refsection>
26         <title>Arguments</title>
27         <variablelist>
28             <varlistentry>
29                 <term>X</term>
30                 <listitem>
31                     <para>symmetric non negative definite real or complex matrix</para>
32                 </listitem>
33             </varlistentry>
34         </variablelist>
35     </refsection>
36     <refsection>
37         <title>Description</title>
38         <para>
39             returns W such that  <literal>X=W*W'</literal> (uses SVD).
40         </para>
41     </refsection>
42     <refsection>
43         <title>Examples</title>
44         <programlisting role="example"><![CDATA[ 
45 X=rand(5,2)*rand(2,5);X=X*X';
46 W=sqroot(X)
47 norm(W*W'-X,1)
48
49 X=rand(5,2)+%i*rand(5,2);X=X*X';
50 W=sqroot(X)
51 norm(W*W'-X,1)
52  ]]></programlisting>
53     </refsection>
54     <refsection role="see also">
55         <title>See Also</title>
56         <simplelist type="inline">
57             <member>
58                 <link linkend="chol">chol</link>
59             </member>
60             <member>
61                 <link linkend="svd">svd</link>
62             </member>
63         </simplelist>
64     </refsection>
65 </refentry>