5.208. k_same_interval
| DESCRIPTION | LINKS | GRAPH |
- Origin
- Constraint
- Type
- Arguments
- Restrictions
- Purpose
Given a collection of sets, each containing the same number of domain variables, the constraint forces a constraint between each pair of consecutive sets.
- Example
-
In the example, the second argument of the constraint defines the following family of intervals , where is an integer. The constraint holds since:
The first and second collections of variables are assigned 4 values in the interval as well as 2 values in the interval .
The second and third collections of variables are also assigned 4 values in the interval as well as 2 values in the interval .
- Typical
- Symmetries
Items of are permutable.
Items of are permutable.
An occurrence of a value of that belongs to the -th interval, of size , can be replaced by any other value of the same interval.
- Arg. properties
Contractible wrt. .
- See also
common keyword: Β (system of constraints).
implies: .
- Keywords
characteristic of a constraint: sort based reformulation.
combinatorial object: permutation.
- Arc input(s)
- Arc generator
-
- Arc arity
- Arc constraint(s)
- Graph property(ies)
-
- Graph model
PartsΒ (A) andΒ (B) of FigureΒ 5.208.1 respectively show the initial and final graph associated with the Example slot. To each vertex corresponds a collection of variables, while to each arc corresponds a constraint.
Figure 5.208.1. Initial and final graph of the constraint
(a) (b)