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Polyhedra :: maxCones

maxCones -- displays the generating Cones of a Fan

Synopsis

Description

maxCones displays the List of generating cones of the Fan, i.e. all Cones that are not a face of one of the other cones. These are all of the same dimension if and only if the Fan is pure (see: isPure).

i1 : F = normalFan crossPolytope 3

o1 = F

o1 : Fan
i2 : L = maxCones F

o2 = {{1, 3, 5, 7}, {0, 2, 4, 6}, {2, 3, 6, 7}, {0, 1, 4, 5}, {4, 5, 6, 7},
     ------------------------------------------------------------------------
     {0, 1, 2, 3}}

o2 : List
i3 : raysF = rays F

o3 = | -1 1  -1 1  -1 1  -1 1 |
     | -1 -1 1  1  -1 -1 1  1 |
     | -1 -1 -1 -1 1  1  1  1 |

              3        8
o3 : Matrix ZZ  <--- ZZ
i4 : apply(L, mc -> raysF_mc)

o4 = {| 1  1  1  1 |, | -1 -1 -1 -1 |, | -1 1  -1 1 |, | -1 1  -1 1  |, | -1
      | -1 1  -1 1 |  | -1 1  -1 1  |  | 1  1  1  1 |  | -1 -1 -1 -1 |  | -1
      | -1 -1 1  1 |  | -1 -1 1  1  |  | -1 -1 1  1 |  | -1 -1 1  1  |  | 1 
     ------------------------------------------------------------------------
     1  -1 1 |, | -1 1  -1 1  |}
     -1 1  1 |  | -1 -1 1  1  |
     1  1  1 |  | -1 -1 -1 -1 |

o4 : List

Ways to use maxCones :

For the programmer

The object maxCones is a method function.