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<p>&nbsp;<p>
<hr noshade size="5">
<h2><a name="Ideal2EltKnown"></a>
Ideal2EltKnown
</h2>

Returns <tt> true</tt> if the ideal is given in two element representation.

<p><p>

<h3>
Syntax:
</h3>
<pre>b := Ideal2EltKnown(I);</pre>

<p>

<table>
<tr>
<td>Boolean </td>
<td><pre>  b  </pre></td>
<td></td>
</tr>
<tr>
<td>ideal </td>
<td><pre>  I  </pre></td>
<td></td>
</tr>
</table>

<p>


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

<p>

<h3>
Description:
</h3>
The representation is not computed, this is only a
check. This function is useful when programming in kash if
an algorithm can handle both basis and
2-element-representation
but prefers the 2-element-representation. The
computation of the 2-element-representation can be
cumbersome in large orders because it involves a
trial-and-error algorithm. So it can be handy just to check
if the 2-element-representation is already present.

<p><p>

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

<pre>

kash> O := OrderMaximal(Order(Poly(Zx, [1, 6, 6, 6])));;
kash> Lp := Factor(6*O);
[ [ <2, [0, 1, 0]>, 3 ], [ <3, [0, 1, 0]>, 3 ] ]
kash> I := Lp[1][1]*Lp[2][1];
<
[6 0 0]
[0 1 0]
[0 0 1]
>

kash> Ideal2EltKnown(I);
false
kash> IdealGenerators(I);
[ 6, [0, 1, 35] ]
kash> Ideal2EltKnown(I);
> true

</pre>

<p>


<hr>

<p>
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