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<A NAME=Smithex>

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



<B>SMITHEX</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
<P>
 
The operator <em>smithex</em> computes the Smith normal form S of a 

<A HREF=r37_0345.html>matrix</A> A (say). It returns {S,P,P^-1} where P*S*P^-1 =
 A. 
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<P>
 <P> <H3> 
syntax: </H3>
<em>smithex</em>(&lt;matrix&gt;,&lt;variable&gt;) 
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<P>
&lt;matrix&gt; :- a rectangular 
<A HREF=r37_0345.html>matrix</A> of univariate polynomials in 
 &lt;variable&gt;. 
&lt;variable&gt; :- the variable. 
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<P>
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 <P> <H3> 
examples: </H3>
<P><PRE><TT>
 a := mat((x,x+1),(0,3*x^2)); 

        [x  x + 1]
        [        ]
   a := [      2 ]
        [0  3*x  ]



 smithex(a,x); 

     [1  0 ]    [1    0]    [x   x + 1]
  {  [     ],   [      ],   [         ]  }
     [    3]    [   2  ]    [         ]
     [0  x ]    [3*x  1]    [-3    -3 ]

</TT></PRE><P>