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Posets :: subPoset

subPoset -- returns the subposet supported on elements in a given list

Synopsis

Description

This command take a poset P and returns a new poset that contains all elements in P that are in L. The relations on the remaining elements are all relations that held in P.
i1 : P = poset({a,b,c,d,e,f,g}, {(a,b), (a,c), (a,d), (b,e), (c,e), (c,f), (d,f), (e,g), (f,g)})

o1 = Poset{cache => CacheTable{}                                                                }
           GroundSet => {a, b, c, d, e, f, g}
           RelationMatrix => | 1 1 1 1 1 1 1 |
                             | 0 1 0 0 1 0 1 |
                             | 0 0 1 0 1 1 1 |
                             | 0 0 0 1 0 1 1 |
                             | 0 0 0 0 1 0 1 |
                             | 0 0 0 0 0 1 1 |
                             | 0 0 0 0 0 0 1 |
           Relations => {(a, b), (a, c), (a, d), (b, e), (c, e), (c, f), (d, f), (e, g), (f, g)}

o1 : Poset
i2 : subPoset(P, {a,e,g})

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

o2 : Poset

See also

Ways to use subPoset :