File r37/lisp/csl/html/r37_0615.html artifact 0890e14697 part of check-in 52fc28dabe

<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>
<P>
 
<P>
<P>
 <P> <H3> 
syntax: </H3>
<em>sub_matrix</em>(&lt;matrix&gt;,&lt;row\_list&gt;,&lt;column\_list&gt;) 
<P>
<P>
<P>
&lt;matrix&gt; :- a matrix. 
&lt;row\_list&gt;, &lt;column\_list&gt; :- either a positive integer or a 
 list of positive integers. 
<P>
<P>
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;. 
<P>
<P>
 <P> <H3> 
examples: </H3>
<P><PRE><TT>

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>. 
<P>
<P>