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<p>&nbsp;<p>
<hr noshade size="5">
<h2><a name="EltRepMat"></a>
EltRepMat
</h2>

A representation matrix of an algebraic element over o
together with a suitable denominator.

<p><p>

<h3>
Syntax:
</h3>
<pre>L := EltRepMat(a[,o]);</pre>

<p>

<table>
<tr>
<td>list</td>
<td><pre>  L  </pre></td>
<td></td>
</tr>
<tr>
<td>algebraic element</td>
<td><pre>  a  </pre></td>
<td></td>
</tr>
<tr>
<td>order</td>
<td><pre>  o  </pre></td>
<td>must be a direct suborder of EltOrder (a)</td>
</tr>
</table>

<p>


<h3>
Description:
</h3>
Given an algebraic element a in an order O and another order o,
such that o is a direct suborder of O, this function computes
a list consisting of an integer den and a matrix M, such that
1/den cdot M is a representation matrix of a with coefficients
in o.

<p><p>

<p>
<hr>
<p>
<h3>
Example:
</h3>
The representation matrix of certain algebraic elements. 
<pre>

kash> o := Order (Poly(Zx,[1,0,73,-280,-2399]));
Generating polynomial: x^4 + 73*x^2 - 280*x - 2399

kash> O1 := Order (o,2,2);
      F[1]
        /
       /
   E1[1]
  /
 /
Q
F  [ 1]     x^2 - 2
E 1[ 1]     x^4 + 73*x^2 - 280*x - 2399

kash> O2 := Order (O1, 2, 3);
         F[1]
           /
          /
      E2[1]
        /
       /
   E1[1]
  /
 /
Q
F  [ 1]     x^2 - 3
E 2[ 1]     x^2 - 2
E 1[ 1]     x^4 + 73*x^2 - 280*x - 2399

kash> alpha := Elt (O2,[[[1,2,3,4],1],[2,[7,8,9,0]]]/ 34);
[[[1, 2, 3, 4], 1], [2, [7, 8, 9, 0]]] / 34
kash> EltRepMat (alpha,o);
> [ 34, [[1, 2, 3, 4] 2 6 [42, 48, 54, 0]]
    [1 [1, 2, 3, 4] [21, 24, 27, 0] 6]
    [2 [14, 16, 18, 0] [1, 2, 3, 4] 2]
    [[7, 8, 9, 0] 2 1 [1, 2, 3, 4]] ]

</pre>

<p>


<hr>

<p>
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