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Posets :: union

union -- computes the union of two posets

Synopsis

Usage:

R = union(P, Q)

R = P + Q
Inputs:
- P, an instance of the type Poset,
- Q, an instance of the type Poset,
Outputs:
- R, an instance of the type Poset, the union of $P$ and $Q$

Description

The union of two posets is the poset induced by the union of the ground sets and the covering relations.

i1 : union(chain 3, poset {{1,4},{4,5},{5,3}})

o1 = Relation Matrix: | 1 1 1 1 1 |
                      | 0 1 1 0 0 |
                      | 0 0 1 0 0 |
                      | 0 0 1 1 1 |
                      | 0 0 1 0 1 |

o1 : Poset

See also

product

Ways to use `union` :

"union(Poset,Poset)"

For the programmer

The object union is a method function.