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Posets :: subposet

subposet -- computes the induced subposet of a poset given a list of elements

Synopsis

Usage:
Q = subposet(P, L)
Inputs:
- P, an object of class Poset
- L, a list, containing elements in the poset
Outputs:
- Q, an object of class Poset, the induced subposet of P with ground set L

Description

The induced subposet Q on ground set L of a poset P has a partial order induced by the partial order on P.

i1 : C = chain 7;

i2 : subposet(C, {2,3,5,6})

o2 = Poset{cache => CacheTable{}                                        }
           GroundSet => {2, 3, 5, 6}
           RelationMatrix => | 1 1 1 1 |
                             | 0 1 1 1 |
                             | 0 0 1 1 |
                             | 0 0 0 1 |
           Relations => {{2, 3}, {2, 5}, {2, 6}, {3, 5}, {3, 6}, {5, 6}}

o2 : Poset

See also

dropElements -- computes the induced subposet of a poset given a list of elements to remove
poset -- creates a new Poset object

Ways to use `subposet` :

subposet(Poset,List)