4805a6f4290c9c9dc36cc4691dc105e8e1182302
[scilab.git] / scilab / modules / elementary_functions / help / en_US / floating_point / frexp.xml
1 <?xml version="1.0" encoding="UTF-8"?>
2 <!--
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8  * This file is hereby licensed under the terms of the GNU GPL v2.0,
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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.
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15  -->
16 <refentry xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink"
17           xmlns:svg="http://www.w3.org/2000/svg" xmlns:ns5="http://www.w3.org/1999/xhtml"
18           xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:db="http://docbook.org/ns/docbook"
19           xmlns:scilab="http://www.scilab.org" xml:id="frexp" xml:lang="en">
20     <refnamediv>
21         <refname>frexp</refname>
22         <refpurpose>dissect floating-point numbers into base 2 exponent and mantissa
23             <emphasis role="bold">(deprecated)</emphasis>
24         </refpurpose>
25     </refnamediv>
26     <refsynopsisdiv>
27         <title>Syntax</title>
28         <synopsis>[f, e] = frexp(x)</synopsis>
29     </refsynopsisdiv>
30     <refsection>
31         <title>Arguments</title>
32         <variablelist>
33             <varlistentry>
34                 <term>x</term>
35                 <listitem>
36                     <para>real vector or matrix</para>
37                 </listitem>
38             </varlistentry>
39             <varlistentry>
40                 <term>f</term>
41                 <listitem>
42                     <para>array of real values, usually in the range 0.5 ≤ abs(f) &lt; 1.
43                     </para>
44                 </listitem>
45             </varlistentry>
46             <varlistentry>
47                 <term>e</term>
48                 <listitem>
49                     <para>
50                         array of integers that satisfy the equation: <literal>x=f.*2.^e</literal>
51                     </para>
52                 </listitem>
53             </varlistentry>
54         </variablelist>
55     </refsection>
56     <refsection>
57         <title>Description</title>
58         <warning>
59             <literal>frexp()</literal> becomes an internal function in Scilab 6.1.x.
60             Please use <literal>[f,e] = log2(x)</literal> instead.
61         </warning>
62         <para>This function corresponds to the ANSI C function frexp(). Any zeros
63             in <literal>x</literal> produce <literal>f=0</literal> and
64             <literal>e=0</literal>.
65         </para>
66     </refsection>
67     <refsection>
68         <title>Examples</title>
69         <programlisting role="example"><![CDATA[
70 [f,e]=frexp([1,%pi,-3,%eps])
71  ]]></programlisting>
72     </refsection>
73     <refsection role="see also">
74         <title>See also</title>
75         <simplelist type="inline">
76             <member>
77                 <link linkend="log">log</link>
78             </member>
79             <member>
80                 <link linkend="hat">hat</link>
81             </member>
82             <member>
83                 <link linkend="ieee">ieee</link>
84             </member>
85             <member>
86                 <link linkend="log2">log2</link>
87             </member>
88         </simplelist>
89     </refsection>
90     <refsection role="history">
91         <title>History</title>
92         <revhistory>
93             <revision>
94                 <revnumber>6.1.0</revnumber>
95                 <revdescription>
96                     frexp() becomes internal. It is publicly replaced with [f,e]=log2(x).
97                 </revdescription>
98             </revision>
99         </revhistory>
100     </refsection>
101 </refentry>