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# isPointed -- checks if a Cone or Fan is pointed

- Usage:
    `b = isPointed C`
    `b = isPointed F`
- Inputs:
  - C, a convex rational cone
  - F, an instance of the type Fan
- Outputs:
  - b, a Boolean value, true if the Cone or the Fan is pointed, false otherwise

## Description

Tests if a Cone is pointed, i.e. the lineality space is 0. A Fan is pointed if one of its Cones is pointed. This is equivalent to all Cones being pointed.

    i1 : C = coneFromHData(matrix{{1,1,-1},{-1,-1,-1}})

    o1 = C

    o1 : Cone

    i2 : isPointed C

    o2 = false

    i3 : C = intersection{C, coneFromHData(matrix{{1,-1,-1}})}

    o3 = C

    o3 : Cone

    i4 : isPointed C

    o4 = true

## Ways to use isPointed:

- `isPointed(Cone)`
- `isPointed(Fan)`

## For the programmer

The object isPointed is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/Polyhedra/documentation/old_documentation.m2:1343:0.