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

Sets/Displays the iteration depth of root expansions and the
precision for series operations.

<p><p>

<h3>
Syntax:
</h3>
<pre>L := AlffRootParams(F);
L := AlffRootParams(F, n, m);</pre>

<p>

<table>
<tr>
<td>list</td>
<td><pre>  L  </pre></td>
<td></td>
</tr>
<tr>
<td>global function field</td>
<td><pre>  F  </pre></td>
<td></td>
</tr>
<tr>
<td>integer</td>
<td><pre>  n  </pre></td>
<td></td>
</tr>
<tr>
<td>integer</td>
<td><pre>  m  </pre></td>
<td></td>
</tr>
</table>

<p>


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

<p>

<h3>
Description:
</h3>
If the infinite place of k(T) is tamely ramified in F,
all roots of the defining
polynomial f of a global function field F/FF_q(T) can be
expanded into Puiseux series in 1/T. The root expansions are
obtained via the Newton-Puiseux method which computes the roots
up to a given iteration depth n. The roots are represented as a
truncated Puiseux series, and all series operations in F are
performed with precision at least m. If n<25
(m<50) it will be set to n=25 (m=50). These parameters
for the root computation can only be changed before the roots are
computed (<tt> AlffRoots()</tt>). For details see Scho1.

<p><p>

<p>
<hr>
<p>
<h3>
Example:
</h3>
Change iteration depth and precision:
<pre>

kash> AlffInit(FF(5,2));
"Defining global variables: k, w, kT, kTf, kTy, T, y, AlffGlobals"
kash> AlffOrders(y^3+T^4+T+1);
"Defining global variables: F, o, oi, one"
kash> AlffRootParams(F);
[ 25, 50 ]
kash> AlffRootParams(F, 50, 100);
> [ 50, 100 ]

</pre>

<p>


<hr>

<p>
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