File r37/lisp/csl/html/r37_0589.html artifact d38d874954 part of check-in 58a25bf8df

<A NAME=get_columns>

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



<B>GET_COLUMNS</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
<P>
 
Get columns, get rows: 
<P>
<P>
 <P> <H3> 
syntax: </H3>
<em>get_columns</em>(&lt;matrix&gt;,&lt;column\_list&gt;) 
<P>
<P>
<P>
&lt;matrix&gt; :- a 
<A HREF=r37_0345.html>matrix</A>. 
<P>
<P>
&lt;c&gt; :- either a positive integer or a list of positive 
 integers. 
<P>
<P>
<em>get_columns</em>removes the columns of &lt;matrix&gt; specified in 
&lt;column\_list&gt; and returns them as a list of column matrices. 
<P>
<P>
<em>get_rows</em>performs the same task on the rows of &lt;matrix&gt;. 
<P>
<P>
 <P> <H3> 
examples: </H3>
<P><PRE><TT>

get_columns(A,{1,3}); 

  {
   [1]
   [ ]
   [4]
   [ ]
   [7]
   ,
   [3]
   [ ]
   [6]
   [ ]
   [9]
  }



get_rows(A,2); 

  {
   [4  5  6]
  }

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

<A HREF=r37_0576.html>augment_columns</A>, 
<A HREF=r37_0614.html>stack_rows</A>, 
<A HREF=r37_0615.html>sub_matrix</A>. 
<P>
<P>