ApCoCoA-1:BB.NDneighbors

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Revision as of 22:46, 7 November 2007 by KHiddemann (talk | contribs) (adding ring to the example)

borderbasis.NDneighbors

list of next-door neighbors

Syntax

$borderbasis.NDneighbors(OO:LIST):LIST

Description

Computes the list of next-door neighbors in the border of the order ideal OO. The input is a list OO of terms that specify an order ideal. The output is a list of triples <formula>[i,j,k]</formula> such that <formula>b_i = x_k * b_j</formula>.

Example

Use Q[x,y,z];
$borderbasis.NDneighbors([1,x]);
[[3, 1, 1], [4, 2, 1]]
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borderbasis.ASneighbors