* Bug 15859 fixed: isempty() overloadable for tlists & mlists
[scilab.git] / scilab / modules / elementary_functions / help / en_US / isempty.xml
1 <?xml version="1.0" encoding="UTF-8"?>
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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="isempty" xml:lang="en">
20     <refnamediv>
21         <refname>isempty</refname>
22         <refpurpose>check if a variable is an empty matrix or an empty
23             list
24         </refpurpose>
25     </refnamediv>
26     <refsynopsisdiv>
27         <title>Syntax</title>
28         <synopsis>t=isempty(x)</synopsis>
29     </refsynopsisdiv>
30     <refsection>
31         <title>Arguments</title>
32         <variablelist>
33             <varlistentry>
34                 <term>x</term>
35                 <listitem>
36                     <para>vector, matrix or list</para>
37                 </listitem>
38             </varlistentry>
39             <varlistentry>
40                 <term>t</term>
41                 <listitem>
42                     <para>a boolean</para>
43                 </listitem>
44             </varlistentry>
45         </variablelist>
46     </refsection>
47     <refsection>
48         <title>Description</title>
49         <para>
50             <literal>isempty(x)</literal> returns true if <literal>x</literal> is an empty matrix
51             or an empty list.
52         </para>
53         <para>
54           <note>
55             isempty() can be overloaded for custom t-lists and m-lists typeof.
56           </note>
57         </para>
58     </refsection>
59     <refsection>
60         <title>Examples</title>
61         <programlisting role="example"><![CDATA[
62 a=1
63 isempty(a(2:$))
64 isempty(find(rand(1:10)==5))
65  ]]></programlisting>
66     </refsection>
67     <refsection role="see also">
68         <title>See also</title>
69         <simplelist type="inline">
70             <member>
71                 <link linkend="empty">[]</link>
72             </member>
73             <member>
74                 <link linkend="emptystr">emptystr</link>
75             </member>
76             <member>
77                 <link linkend="size">size</link>
78             </member>
79             <member>
80                 <link linkend="length">length</link>
81             </member>
82         </simplelist>
83     </refsection>
84     <refsection role="history">
85         <title>History</title>
86         <revhistory>
87             <revision>
88                 <revnumber>6.0.2</revnumber>
89                 <revdescription>
90                     isempty() can now be overloaded for custom tlist and mlist typeof.
91                 </revdescription>
92             </revision>
93         </revhistory>
94     </refsection>
95 </refentry>