5.281. nor

DESCRIPTIONLINKSAUTOMATON
Origin

Logic

Constraint

πš—πš˜πš›(πš…π™°πš,πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚)

Synonym

πšŒπš•πšŠπšžπšœπšŽ.

Arguments
πš…π™°πšπšπšŸπšŠπš›
πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚πšŒπš˜πš•πš•πšŽπšŒπšπš’πš˜πš—(πšŸπšŠπš›-πšπšŸπšŠπš›)
Restrictions
πš…π™°πšβ‰₯0
πš…π™°πšβ‰€1
|πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚|β‰₯2
πš›πšŽπššπšžπš’πš›πšŽπš(πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚,πšŸπšŠπš›)
πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚.πšŸπšŠπš›β‰₯0
πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚.πšŸπšŠπš›β‰€1
Purpose

Let πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚ be a collection of 0-1 variables πš…π™°πš 1 ,πš…π™°πš 2 ,β‹―,πš…π™°πš n (nβ‰₯2). Enforce πš…π™°πš=Β¬(πš…π™°πš 1 βˆ¨πš…π™°πš 2 βˆ¨β‹―βˆ¨πš…π™°πš n ).

Example
(1,0,0)
(0,0,1)
(0,1,0)
(0,1,1)
(0,1,0,1)
Symmetry

Items of πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚ are permutable.

Arg. properties
  • Functional dependency: πš…π™°πš determined by πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚.

  • Contractible wrt. πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚ when πš…π™°πš=1.

  • Extensible wrt. πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚ when πš…π™°πš=0.

  • Aggregate: πš…π™°πš(∧), πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚(πšžπš—πš’πš˜πš—).

Counting
Length (n)2345678
Solutions48163264128256

Number of solutions for πš—πš˜πš›: domains 0..n

ctrs/nor-1-tikz

ctrs/nor-2-tikz

Length (n)2345678
Total48163264128256
Parameter
value

037153163127255
11111111

Solution count for πš—πš˜πš›: domains 0..n

ctrs/nor-3-tikz

ctrs/nor-4-tikz

Systems

reifiedXnor in Choco, clause in Gecode, #\/ in SICStus.

See also

common keyword: πšŠπš—πš, πšŽπššπšžπš’πšŸπšŠπš•πšŽπš—πš, πš’πš–πš™πš•πš’, πš—πšŠπš—πš, πš˜πš›, πš‘πš˜πš›Β (Boolean constraint).

implies: πšŠπšπš•πšŽπšŠπšœπš_πš—πšŸπšŠπš•πšžπšŽ, 𝚜𝚘𝚏𝚝_πšŠπš•πš•_πšŽπššπšžπšŠπš•_πš–πš’πš—_πšŒπšπš›.

Keywords

characteristic of a constraint: automaton, automaton without counters, reified automaton constraint.

constraint arguments: pure functional dependency.

constraint network structure: Berge-acyclic constraint network.

constraint type: Boolean constraint.

filtering: arc-consistency.

modelling: functional dependency.

Cond. implications

πš—πš˜πš›(πš…π™°πš,πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚)

Β Β Β  withΒ  |πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚|>2

Β Β implies πšœπš˜πš–πšŽ_πšŽπššπšžπšŠπš•(πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚).

Automaton

FigureΒ 5.281.1 depicts the automaton associated with the πš—πš˜πš› constraint. To the first argument πš…π™°πš of the πš—πš˜πš› constraint corresponds the first signature variable. To each variable πš…π™°πš i of the second argument πš…π™°πšπ™Έπ™°π™±π™»π™΄πš‚ of the πš—πš˜πš› constraint corresponds the next signature variable. There is no signature constraint.

Figure 5.281.1. Automaton of the πš—πš˜πš› constraint
ctrs/nor-5-tikz
Figure 5.281.2. Hypergraph of the reformulation corresponding to the automaton of the πš—πš˜πš› constraint
ctrs/nor-6-tikz