5.78. common_partition
DESCRIPTION | LINKS | GRAPH |
- Origin
- Constraint
- Type
- Arguments
- Restrictions
- Purpose
is the number of variables of the collection taking a value in a partition derived from the values assigned to the variables of and from .
is the number of variables of the collection taking a value in a partition derived from the values assigned to the variables of and from .
- Example
-
In the example, the last argument defines the partitions , and . As a consequence the first three items of collection respectively correspond to the partitions , , and . Similarly the items of collection (from which we remove items 0 and 7 since they do not belong to any partition) respectively correspond to the partitions , , , and . The constraint holds since:
Its first argument is the number of partitions associated with the items of collection that also correspond to partitions associated with .
Its second argument is the number of partitions associated with the items of collection that also correspond to partitions associated with .
- Typical
- Symmetries
Arguments are permutable w.r.t. permutation .
Items of are permutable.
Items of are permutable.
Items of are permutable.
Items of are permutable.
An occurrence of a value of can be replaced by any other value that also belongs to the same partition of .
An occurrence of a value of can be replaced by any other value that also belongs to the same partition of .
- Arg. properties
Functional dependency: determined by , and .
Functional dependency: determined by , and .
- See also
specialisation: Β ( replaced by ).
- Keywords
characteristic of a constraint: partition.
constraint arguments: constraint between two collections of variables, pure functional dependency.
- Arc input(s)
- Arc generator
-
- Arc arity
- Arc constraint(s)
- Graph property(ies)
-
- Graph class
-
- Graph model
PartsΒ (A) andΒ (B) of FigureΒ 5.78.1 respectively show the initial and final graph associated with the Example slot. Since we use the and graph properties, the source and sink vertices of the final graph are stressed with a double circle. Since the graph has only 3 sources and 4 sinks the variables and are respectively equal to 3 and 4. Note that the vertices corresponding to the variables that take values 0 or 7 were removed from the final graph since there is no arc for which the associated constraint holds.
Figure 5.78.1. Initial and final graph of the constraint
(a) (b)