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

Computes the fix point group of endomorphisms.

<p><p>

<h3>
Syntax:
</h3>
<pre>f := AbelianFixPointGroup(hom);
f := AbelianFixPointGroup(L);</pre>

<p>

<table>
<tr>
<td>group</td>
<td><pre>  f  </pre></td>
<td></td>
</tr>
<tr>
<td>homomorphism</td>
<td><pre>  hom  </pre></td>
<td></td>
</tr>
<tr>
<td>list</td>
<td><pre>  L  </pre></td>
<td>list of homomorphisms</td>
</tr>
</table>

<p>


<h3>
Description:
</h3>
Computes the group consisting of elements that are
(pointwise) fix under each given endomorphism.


<p><p>

<p>
<hr>
<p>
<h3>
Example:
</h3>
Compute the fix point group and apply an endomorphism: 
<pre>

kash> g := AbelianGroupCreate([[0,0],[0,60]]);;
kash> mat := Mat(Z, [[1,1], [0,1]]);;
kash> hom := AbelianGroupHomCreate(g, g, mat, true);
HomMatrix =
[1 1]
[0 1] 
from Group with relations:
[ 0  0]
[ 0 60] 
to Group with relations:
[ 0  0]
[ 0 60]

kash> f := AbelianFixPointGroup(hom);
Group with relations:
[60  0]
[ 0  0]
kash> elt := AbelianGroupEltCreate(f, [1,2]);
[1 2]
kash> elt := AbelianGroupEltMove(elt, g);
[120   1]
kash> hom*elt;
> [120   1]

</pre>

<p>


<hr>

<p>
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