5.10. all_incomparable

DESCRIPTIONLINKSGRAPH
Origin

Inspired by incomparable rectangles.

Constraint

πšŠπš•πš•_πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ(πš…π™΄π™²πšƒπ™Ύπšπš‚)

Synonym

πšŠπš•πš•_πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽπšœ.

Type
πš…π™΄π™²πšƒπ™Ύπ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›)
Argument
πš…π™΄π™²πšƒπ™Ύπšπš‚πšŒπš˜πš•πš•πšŽπšŒπšπš’πš˜πš—(𝚟𝚎𝚌-πš…π™΄π™²πšƒπ™Ύπš)
Restrictions
πš›πšŽπššπšžπš’πš›πšŽπš(πš…π™΄π™²πšƒπ™Ύπš,πšŸπšŠπš›)
|πš…π™΄π™²πšƒπ™Ύπš|β‰₯1
πš›πšŽπššπšžπš’πš›πšŽπš(πš…π™΄π™²πšƒπ™Ύπšπš‚,𝚟𝚎𝚌)
|πš…π™΄π™²πšƒπ™Ύπšπš‚|β‰₯1
πšœπšŠπš–πšŽ_πšœπš’πš£πšŽ(πš…π™΄π™²πšƒπ™Ύπšπš‚,𝚟𝚎𝚌)
Purpose

Enforce for each pair of distinct vectors of the πš…π™΄π™²πšƒπ™Ύπšπš‚ collection the fact that they are incomparable. Two vectors πš…π™΄π™²πšƒπ™Ύπš1 and πš…π™΄π™²πšƒπ™Ύπš2 are incomparable if and only, when the components of both vectors are ordered, and respectively denoted by πš‚πš…π™΄π™²πšƒπ™Ύπš1 and πš‚πš…π™΄π™²πšƒπ™Ύπš2, we neither have πš‚πš…π™΄π™²πšƒπ™Ύπš1[i].πšŸπšŠπš›β‰€πš‚πš…π™΄π™²πšƒπ™Ύπš2[i].πšŸπšŠπš› (for all i∈[1,|πš‚πš…π™΄π™²πšƒπ™Ύπš1|]) nor have πš‚πš…π™΄π™²πšƒπ™Ύπš2[i].πšŸπšŠπš›β‰€πš‚πš…π™΄π™²πšƒπ™Ύπš1[i].πšŸπšŠπš› (for all i∈[1,|πš‚πš…π™΄π™²πšƒπ™Ύπš1|]).

Example
𝚟𝚎𝚌-1,18,𝚟𝚎𝚌-2,16,𝚟𝚎𝚌-3,13,𝚟𝚎𝚌-4,11,𝚟𝚎𝚌-5,10,𝚟𝚎𝚌-6,9,𝚟𝚎𝚌-7,7

The πšŠπš•πš•_πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ constraint holds since all distinct pairs of vectors are incomparable as illustrated by FigureΒ 5.10.1.

Figure 5.10.1. Illustrating the incomparability of vectors 〈1,18βŒͺ, 〈2,16βŒͺ, 〈3,13βŒͺ, 〈4,11βŒͺ, 〈5,10βŒͺ, 〈6,9βŒͺ, 〈7,7βŒͺ: first to each vector we associate a rectangle whose sizes are the components of the vector; second no matter whether we rotate a rectangle from 90 ∘ or not, one rectangle can not be included in another rectangle.
ctrs/all_incomparable-1-tikz
All solutions

FigureΒ 5.10.2 gives all solutions to the following non ground instance of the πšŠπš•πš•_πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ constraint: U 1 ∈[1,2], V 1 ∈[0,5], U 2 ∈[3,5], V 2 ∈[2,3], U 3 ∈[0,6], V 3 ∈[2,5], πšŠπš•πš•_πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ(〈〈U 1 ,V 1 βŒͺ,〈U 2 ,V 2 βŒͺ,〈U 3 ,V 3 βŒͺβŒͺ).

Figure 5.10.2. All solutions corresponding to the non ground example of the πšŠπš•πš•_πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ constraint of the All solutions slot
ctrs/all_incomparable-2-tikz
Typical
|πš…π™΄π™²πšƒπ™Ύπš|>1
|πš…π™΄π™²πšƒπ™Ύπšπš‚|>1
|πš…π™΄π™²πšƒπ™Ύπšπš‚|>|πš…π™΄π™²πšƒπ™Ύπš|
Symmetry

Items of πš…π™΄π™²πšƒπ™Ύπšπš‚ are permutable.

Arg. properties

Contractible wrt. πš…π™΄π™²πšƒπ™Ύπšπš‚.

See also

implies: πš•πšŽπš‘_πšŠπš•πš•πšπš’πšπšπšŽπš›πšŽπš—πš.

part of system of constraints: πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ.

used in graph description: πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ.

Keywords

characteristic of a constraint: vector.

constraint type: system of constraints, decomposition.

final graph structure: no loop, symmetric.

Cond. implications

β€’ πšŠπš•πš•_πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ(πš…π™΄π™²πšƒπ™Ύπšπš‚)

Β Β Β  withΒ  |πš…π™΄π™²πšƒπ™Ύπš|=2

Β Β implies πš”_πšπš’πšœπš“πš˜πš’πš—πš(πš‚π™΄πšƒπš‚:πš…π™΄π™²πšƒπ™Ύπšπš‚).

β€’ πšŠπš•πš•_πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ(πš…π™΄π™²πšƒπ™Ύπšπš‚)

Β Β Β  withΒ  |πš…π™΄π™²πšƒπ™Ύπš|=2

Β Β implies πšπš πš’πš—(π™Ώπ™°π™Έπšπš‚:πš…π™΄π™²πšƒπ™Ύπšπš‚).

Arc input(s)

πš…π™΄π™²πšƒπ™Ύπšπš‚

Arc generator
πΆπΏπΌπ‘„π‘ˆπΈ(β‰ )β†¦πšŒπš˜πš•πš•πšŽπšŒπšπš’πš˜πš—(πšŸπšŽπšŒπšπš˜πš›πšœ1,πšŸπšŽπšŒπšπš˜πš›πšœ2)

Arc arity
Arc constraint(s)
πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ(πšŸπšŽπšŒπšπš˜πš›πšœ1.𝚟𝚎𝚌,πšŸπšŽπšŒπšπš˜πš›πšœ2.𝚟𝚎𝚌)
Graph property(ies)
𝐍𝐀𝐑𝐂=|πš…π™΄π™²πšƒπ™Ύπšπš‚|*|πš…π™΄π™²πšƒπ™Ύπšπš‚|-|πš…π™΄π™²πšƒπ™Ύπšπš‚|

Graph class
β€’ 𝙽𝙾_𝙻𝙾𝙾𝙿
β€’ πš‚πšˆπ™Όπ™Όπ™΄πšƒπšπ™Έπ™²

Graph model

The Arc constraint(s) slot uses the πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ constraint defined in this catalogue.

PartsΒ (A) andΒ (B) of FigureΒ 5.10.3 respectively show the initial and final graph associated with the Example slot. Since we use the 𝐍𝐀𝐑𝐂 graph property, the arcs of the final graph are stressed in bold. The previous constraint holds since exactly 3Β·(3-1)=6 arc constraints hold.

Figure 5.10.3. Initial and final graph of the πšŠπš•πš•_πš’πš—πšŒπš˜πš–πš™πšŠπš›πšŠπš‹πš•πšŽ constraint
ctrs/all_incomparableActrs/all_incomparableB
(a) (b)