Difference between revisions of "ApCoCoA-1:BB.ASneighbors"
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(... and this time really added an example ;-)) |
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<description> | <description> | ||
Computes the list of across-the-street neighbors in the border of the order ideal OO. The input is a list of terms OO that specifies an order ideal. The output is a list of quadruples <formula>[i,j,k,l]</formula> such that <formula>x_k * b_i = x_l * b_j</formula>. | Computes the list of across-the-street neighbors in the border of the order ideal OO. The input is a list of terms OO that specifies an order ideal. The output is a list of quadruples <formula>[i,j,k,l]</formula> such that <formula>x_k * b_i = x_l * b_j</formula>. | ||
+ | <example> | ||
+ | ASneighbors([1,x]); | ||
+ | [[1, 2, 2, 3], [3, 4, 2, 3], [3, 5, 1, 3], [4, 5, 1, 2]] | ||
+ | ------------------------------- | ||
+ | </example> | ||
</description> | </description> | ||
<see>borderbasis.NDneighbors</see> | <see>borderbasis.NDneighbors</see> |
Revision as of 20:22, 7 November 2007
borderbasis.ASneighbors
compute list of across-the-street neighbors
Syntax
$borderbasis.ASneighbors(OO:LIST):LIST
Description
Computes the list of across-the-street neighbors in the border of the order ideal OO. The input is a list of terms OO that specifies an order ideal. The output is a list of quadruples <formula>[i,j,k,l]</formula> such that <formula>x_k * b_i = x_l * b_j</formula>.
Example
ASneighbors([1,x]); [[1, 2, 2, 3], [3, 4, 2, 3], [3, 5, 1, 3], [4, 5, 1, 2]] -------------------------------