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

Discrete logarithm for finite fields.

<p><p>

<h3>
Syntax:
</h3>
<pre>d := FFEltLog(a);</pre>

<p>

<table>
<tr>
<td>finite field element</td>
<td><pre>  a  </pre></td>
<td></td>
</tr>
<tr>
<td>integer</td>
<td><pre>  d  </pre></td>
<td></td>
</tr>
</table>

<p>


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

<p>

<h3>
Description:
</h3>
This function computes the discrete logarithm of an
element a with respect to a primitive element omega, that means
a non negative integer d with a = omega^d. The primitive element
omega is that returned by <tt> FFPrimitiveElt()</tt>.

<p><p>

<p>
<hr>
<p>
<h3>
Example:
</h3>
Compute some discrete logarithms:
<pre>

kash> F125 := FF(5, 3);
Finite field of size 5^3
kash> a := FFElt(F125, 3);
3
kash> d := FFEltLog(a);
93
kash> w := FFPrimitiveElt(F125);
w
kash> w^d;
3
kash> FFEltLog(w^47);
> 47

</pre>

<p>


<hr>

<p>
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