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Poset -- a class for partially ordered sets (posets)

Description

This class is a type of HashTable which represents finite posets. It consists of a ground set, a set of sequences (a,b) representing relationships where a is less than or equal to b, a matrix encoding these relations.
i1 : G = {a,b,c,d,e}; -- the ground set
i2 : R = {(a,b),(b,c),(a,c),(a,d),(d,e)}; --a set of sequences representing relations that "generate" all other relations
i3 : P = poset (G,R) -- the matrix encoding these relations is computed by calling this function

o3 = Poset{cache => CacheTable                                  }
           GroundSet => {a, b, c, d, e}
           RelationMatrix => | 1 1 1 1 1 |
                             | 0 1 1 0 0 |
                             | 0 0 1 0 0 |
                             | 0 0 0 1 1 |
                             | 0 0 0 0 1 |
           Relations => {(a, b), (b, c), (a, c), (a, d), (d, e)}

o3 : Poset

See also

Functions and methods returning an object of class Poset :

Methods that use an object of class Poset :

For the programmer

The object Poset is a type, with ancestor classes HashTable < Thing.