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

Return the valuation of an ideal at a prime ideal.

<p><p>

<h3>
Syntax:
</h3>
<pre>v := AlffIdealValuation(P, I);</pre>

<p>

<table>
<tr>
<td>integer</td>
<td><pre>  v  </pre></td>
<td></td>
</tr>
<tr>
<td>alff order ideals</td>
<td><pre>  P, I  </pre></td>
<td>in maximal order o</td>
</tr>
</table>

<p>


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

<p>

<h3>
Description:
</h3>
This function returns the valuation of an ideal at a prime
ideal. They have to be defined in the same order which
must be maximal (i.~e.~a Dedekind ring).

<p><p>

<p>
<hr>
<p>
<h3>
Example:
</h3>
Compute a valuation:
<pre>

kash> AlffInit(FF(5,2));
"Defining global variables: k, w, kT, kTf, kTy, T, y, AlffGlobals"
kash> AlffOrders(y^3+T^4+1);
"Defining global variables: F, o, oi, one"
kash> a := AlffElt(o, [0, 1, 0]);
[ 0, 1, 0 ]
kash> I := (T + w^3)*o + a*o;
< 
[ T + w^3        0        0]
[       0        1        0]
[       0        0        1]
/ 1
 >
kash> P := AlffIdealFactor(I)[1][1];
< [ T + w^3, 0, 0 ], [ 0, 1, 0 ] >
kash> AlffIdealValuation(P, I^(-2));
> -2

</pre>

<p>


<hr>

<p>
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