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joinIrreducibles -- determines the join irreducible elements of a poset

Usage:

J = joinIrreducibles P
Inputs:
- P, an instance of the type Poset,
Outputs:
- J, a list,

Description

An element $a$ of $P$ is join irreducible if it is not the join of any set of elements not containing $a$.

i1 : joinIrreducibles booleanLattice 3

o1 = {000, 001, 100, 010}

o1 : List

See also

joinExists -- determines if the join exists for two elements of a poset
meetIrreducibles -- determines the meet irreducible elements of a poset
posetJoin -- determines the join for two elements of a poset

Ways to use joinIrreducibles:

joinIrreducibles(Poset)

For the programmer

The object joinIrreducibles is a method function.

The source of this document is in /__w/M2/M2/macaulay2-1.26.05+ds/M2/Macaulay2/packages/Posets.m2:4487:0.