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Posets :: closedInterval

closedInterval -- returns the closed interval in the poset between two elements

Synopsis

Description

This routine returns the interval between the elements a and b in P, including a and b, and an error message if the two elements are not comparable in P.

i1 : P = poset({a,b,c,d},{(a,b),(b,c),(b,d)});
i2 : closedInterval(P,a,d)

o2 = Poset{cache => CacheTable{}                                        }
           GroundSet => {a, b, d}
           RelationMatrix => | 1 1 1 |
                             | 0 1 1 |
                             | 0 0 1 |
           Relations => {(a, a), (a, b), (a, d), (b, b), (b, d), (d, d)}

o2 : Poset

Ways to use closedInterval :

  • closedInterval(Poset,Thing,Thing)