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<A NAME=sub_matrix>

<TITLE>sub_matrix</TITLE></A>
<b><a href=r37_idx.html>INDEX</a></b><p><p>



<B>SUB_MATRIX</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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syntax: </H3>
<em>sub_matrix</em>(&lt;matrix&gt;,&lt;row\_list&gt;,&lt;column\_list&gt;) 
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&lt;matrix&gt; :- a matrix. 
&lt;row\_list&gt;, &lt;column\_list&gt; :- either a positive integer or a 
 list of positive integers. 
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namesub_matrix produces the matrix consisting of the intersection of 
the rows specified in &lt;row\_list&gt; and the columns specified in 
&lt;column\_list&gt;. 
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examples: </H3>
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sub_matrix(A,{1,3},{2,3}); 

  [2  3]
  [    ]
  [8  9]

</TT></PRE><P>Related functions: 

<A HREF=r37_0576.html>augment_columns</A>, 
<A HREF=r37_0614.html>stack_rows</A>. 
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