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Polyhedra :: facesAsCones

facesAsCones -- Returns the faces of a cone as actual cones.

Synopsis

Description

While faces returns a list of lists of indices for the rays that make up the codimension n faces, this gives a list of actual cones. It is just a small wrapper around faces. Whenever possible, use faces instead.

i1 : L = facesAsCones(1, posOrthant 2)

o1 = {Cone{...1...}, Cone{...1...}}

o1 : List
i2 : rays L#0

o2 = | 0 |
     | 1 |

              2        1
o2 : Matrix ZZ  <--- ZZ
i3 : rays L#1

o3 = | 1 |
     | 0 |

              2        1
o3 : Matrix ZZ  <--- ZZ
i4 : F = normalFan hypercube 2

o4 = F

o4 : Fan
i5 : L = facesAsCones(1, F)

o5 = {Cone{...1...}, Cone{...1...}, Cone{...1...}, Cone{...1...}}

o5 : List
i6 : rays L#0

o6 = | -1 |
     | 0  |

              2        1
o6 : Matrix ZZ  <--- ZZ

Ways to use facesAsCones :