Difference between revisions of "ApCoCoA-1:BB.ASneighbors"

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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>
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ASneighbors([1,x]);
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[[1, 2, 2, 3], [3, 4, 2, 3], [3, 5, 1, 3], [4, 5, 1, 2]]
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-------------------------------
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</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]]
-------------------------------

borderbasis.NDneighbors