5.82. cond_lex_greatereq
DESCRIPTION | LINKS | AUTOMATON |
- Origin
Inspired by [WallaceWilson06].
- Constraint
- Type
- Arguments
- Restrictions
- Purpose
and are both assigned to the and items of the collection such that .
- Example
-
The constraint holds since and are respectively assigned to the third and first items of the collection .
- Typical
- Symmetries
Items of , and are permutable (same permutation used).
All occurrences of two distinct tuples of values in , or can be swapped; all occurrences of a tuple of values in , or can be renamed to any unused tuple of values.
- Usage
- See also
common keyword: , , , Β (preferences), Β (lexicographic order).
- Keywords
characteristic of a constraint: vector, automaton.
constraint network structure: Berge-acyclic constraint network.
- Automaton
FigureΒ 5.82.1 depicts the automaton associated with the preference table of the constraint given in the example. Let and respectively be the attributes of the items of the and the collections. FigureΒ 5.82.2 depicts the reformulation of the constraint. This reformulation uses:
Two occurrences of the automaton depicted by FigureΒ 5.82.1 for computing the positions and within the preference table corresponding to and .
The binary constraint .
Figure 5.82.1. Automaton associated with the preference table of the constraint given in the Example slot
Figure 5.82.2. Hypergraph of the reformulation corresponding to the constraint: it uses two occurrences of the automaton of FigureΒ 5.82.1 and the constraint