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smoothSubfan -- computes the subfan of all smooth cones

Synopsis

Description

For a given Fan F the function computes the subfan F1 of all smooth cones.

Let's consider the fan consisting of the following three dimensional cone and all of its faces:
i1 : C = coneFromVData  matrix {{1,-1,0},{1,1,0},{1,1,1}}

o1 = C

o1 : Cone
i2 : F = fan C

o2 = F

o2 : Fan

This cone is not smooth, therefore also the fan is not. But if we remove the interior and one of the two dimensional faces the resulting subfan is smooth.
i3 : F1 = smoothSubfan F

o3 = F1

o3 : Fan
i4 : raysF1 = rays F1

o4 = | 0 -1 1 |
     | 0 1  1 |
     | 1 1  1 |

              3       3
o4 : Matrix ZZ  <-- ZZ
i5 : apply(maxCones F1, mc -> raysF1_mc)

o5 = {| 0 -1 |, | 0 1 |}
      | 0 1  |  | 0 1 |
      | 1 1  |  | 1 1 |

o5 : List

Ways to use smoothSubfan:

For the programmer

The object smoothSubfan is a method function.