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

Computes a reduced divisor.

<p><p>

<h3>
Syntax:
</h3>
<pre>L := AlffDivisorReduction(D);
L := AlffDivisorReduction(D, A);</pre>

<p>

<table>
<tr>
<td>list</td>
<td><pre>  L  </pre></td>
<td>as above</td>
</tr>
<tr>
<td>alff divisor</td>
<td><pre>  D  </pre></td>
<td>to reduce</td>
</tr>
<tr>
<td>alff divisor</td>
<td><pre>  D  </pre></td>
<td></td>
</tr>
</table>

<p>


See also:&nbsp;&nbsp;<a href="kashref.html#AlffDivisorLargeLDim">AlffDivisorLargeLDim</a>

<p>

<h3>
Description:
</h3>
Let A, D be divisors of an algebraic function field F
of genus g and
\deg(A)  &gt;=  1. Let r \in Z be maximal such that
D = \widetilde{D} + rA - (a) with a positive divisor
\widetilde{D} of F and a \in F^\times.
Then \deg(\widetilde{D}) < g + \deg(A) and
\widetilde{D}
is maximally reduced along A. This function returns on
input of D and A
a list containing \widetilde{D}, r, A and a list
((a_{i,j})_j, e_i)_i, such that a = \prod_{i, j} a_{i, j}^{e_i}.
If A is omitted, A := (T)_\infty is taken.
\widetilde{D} is returned in ideal representation. The algorithm
is described in He2.

<p><p>

<p>
<hr>
<p>
<h3>
Example:
</h3>

<pre>

</pre>

<p>


<hr>

<p>
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