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isBounded -- determines if a poset is bounded

Synopsis

Usage:

i = isBounded P
Inputs:
- P, an instance of the type Poset,
Outputs:
- i, a Boolean value, whether $P$ is bounded

Description

The poset $P$ is bounded if it has a unique minimal element and a unique maximal element.

The $n$ chain and $n$ booleanLattice are bounded.

i1 : n = 5;

i2 : isBounded chain n

o2 = true

i3 : B = booleanLattice n;

i4 : isBounded B

o4 = true

The middle ranks of an $n$ boolean lattice are not bounded.

i5 : isBounded flagPoset(B, {1,2,3,4})

o5 = false

See also

maximalElements -- determines the maximal elements of a poset
minimalElements -- determines the minimal elements of a poset

Ways to use isBounded :

isBounded(Poset)

For the programmer

The object isBounded is a method function.