Difference between revisions of "ApCoCoA-1:BB.ASneighbors"
From ApCoCoAWiki
(Added parameter and return value list.) |
(Updated parameter and return value list.) |
||
Line 9: | Line 9: | ||
<itemize> | <itemize> | ||
<item>@param <em>OO</em> A list of terms representing an order ideal.</item> | <item>@param <em>OO</em> A list of terms representing an order ideal.</item> | ||
− | <item>@return A list of across-the-street neighbors of | + | <item>@return A list of across-the-street neighbors of OO.</item> |
</itemize> | </itemize> | ||
<example> | <example> |
Revision as of 13:27, 22 April 2009
BB.ASneighbors
Compute a list of across-the-street neighbors.
Syntax
BB.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 OO of terms that specify 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>.
@param OO A list of terms representing an order ideal.
@return A list of across-the-street neighbors of OO.
Example
Use Q[x,y,z]; BB.ASneighbors([1,x]); [[1, 2, 2, 3], [3, 4, 2, 3], [3, 5, 1, 3], [4, 5, 1, 2]] -------------------------------