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# isBounded -- determines if a poset is bounded

- 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.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/Posets.m2:5576:0.