# Difference between revisions of "ApCoCoA-1:BB.NDneighbors"

From ApCoCoAWiki

KHiddemann (talk | contribs) (adding formula tags) |
(Reviewed text and added example) |
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<command> | <command> | ||

<title>borderbasis.NDneighbors</title> | <title>borderbasis.NDneighbors</title> | ||

− | <short_description> | + | <short_description>computes list of next-door neighbors</short_description> |

<syntax> | <syntax> | ||

$borderbasis.NDneighbors(OO:LIST):LIST | $borderbasis.NDneighbors(OO:LIST):LIST | ||

</syntax> | </syntax> | ||

<description> | <description> | ||

− | Computes the list of next-door neighbors in the border of OO. The input is a list of terms OO | + | Computes the list of next-door neighbors in the border of the order ideal OO. The input is a list of terms OO 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> | ||

+ | NDneighbors([1,x]); | ||

+ | [[3, 1, 1], [4, 2, 1]] | ||

+ | ------------------------------- | ||

+ | </example> | ||

</description> | </description> | ||

+ | <see>borderbasis.ASneighbors</see> | ||

<key>Kreuzer</key> | <key>Kreuzer</key> | ||

<key>borderbasis.ndneighbors</key> | <key>borderbasis.ndneighbors</key> |

## Revision as of 20:25, 7 November 2007

## borderbasis.NDneighbors

computes 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 of terms OO 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

NDneighbors([1,x]); [[3, 1, 1], [4, 2, 1]] -------------------------------