- Origin
[FlenerFrischHnichKiziltanMiguelPearsonWalsh02]
- Constraint
-
- Type
| |
- Argument
| |
- Restrictions
-
- Purpose
Given a matrix of domain variables, enforces that both
adjacent rows, and adjacent columns are lexicographically
ordered (adjacent rows and adjacent columns cannot be equal).
- Example
-
The constraint holds since:
The first row is lexicographically strictly less than
the second row .
The first column is lexicographically strictly less than
the second column .
The second column is lexicographically strictly less than
the third column .
- Typical
|
|
- Symmetry
One and the same constant can be added to the attribute of all items of .
- Usage
A symmetry-breaking constraint.
- Reformulation
The constraint can be expressed as a conjunction
of two constraints:
A first constraint
on the argument and
a second constraint
on the transpose of the argument.
- Systems
strict_lex2 in MiniZinc.
- See also
common keyword:
,
Β (lexicographic order).
implies:
,
.
part of system of constraints:
.
- Keywords
constraint type:
predefined constraint,
system of constraints,
order constraint.
modelling:
matrix,
matrix model.
symmetry:
symmetry,
matrix symmetry,
lexicographic order.
