Xcos load: use a valid port type value
[scilab.git] / scilab / modules / elementary_functions / help / pt_BR / elementarymatrices / empty.xml
1 <?xml version="1.0" encoding="ISO-8859-1"?>
2 <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="empty" xml:lang="en">
3     <refnamediv>
4         <refname>empty</refname>
5         <refpurpose>([]) matriz vazia</refpurpose>
6     </refnamediv>
7     <refsection>
8         <title>Descrição</title>
9         <para>
10             <literal> [] </literal> denota a matriz vazia. É definida de modo
11             único e possui 0 linha e 0 coluna, i.e. <literal> size([]) =[0,0]
12             </literal>
13             .As seguintes convenções convenientes foram feitas:
14         </para>
15         <para>
16             <literal> [] * A = A * [] = [] </literal>
17         </para>
18         <para>
19             <literal> [] + A = A + [] = []</literal>
20         </para>
21         <para>
22             [ [], A] = [A, []] = A <literal> inv([]) =[] </literal>
23         </para>
24         <para>
25             <literal> det([])=cond([])=rcond([])=1, rank([])=0</literal>
26         </para>
27         <para>
28             Funções de matrizes retornam <literal>[]</literal> ou produzem uma
29             mensagem de erro quando não há resposta óbvia. Sistemas lineares vazios
30             (listas<literal> syslin</literal>) podem ter várias linhas ou
31             colunas.
32         </para>
33     </refsection>
34     <refsection>
35         <title>Exemplos</title>
36         <programlisting role="example"><![CDATA[ 
37 s=poly(0,'s');
38 A = [s, s+1]; 
39 A+[], A*[]
40 A=rand(2,2);
41 AA=A([],1), size(AA)
42 svd([])
43 w=ssrand(2,2,2);
44 wr=[]*w;
45 size(wr), w1=ss2tf(wr), size(w1)
46  ]]></programlisting>
47     </refsection>
48     <refsection role="see also">
49         <title>Ver Também</title>
50         <simplelist type="inline">
51             <member>
52                 <link linkend="matrices">matrices</link>
53             </member>
54             <member>
55                 <link linkend="poly">poly</link>
56             </member>
57             <member>
58                 <link linkend="string">string</link>
59             </member>
60             <member>
61                 <link linkend="boolean">boolean</link>
62             </member>
63             <member>
64                 <link linkend="rational">rational</link>
65             </member>
66             <member>
67                 <link linkend="syslin">syslin</link>
68             </member>
69         </simplelist>
70     </refsection>
71 </refentry>