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topcomNumTriangulations(Matrix) -- the number of triangulations of a point or vector configuration

Synopsis

Description

This function is identical in function to topcomAllTriangulations(Matrix) (including optional arguments), but instead just counts the number, rather than enumerate them.

For example, to use the same example as in topcomAllTriangulations(Matrix):

i1 : A = transpose matrix {{0,3},{0,1},{-1,-1},{1,-1},{-4,-2},{4,-2}}

o1 = | 0 0 -1 1  -4 4  |
     | 3 1 -1 -1 -2 -2 |

              2       6
o1 : Matrix ZZ  <-- ZZ
i2 : topcomNumTriangulations A == 16

o2 = true
i3 : topcomNumTriangulations A == # topcomAllTriangulations A

o3 = true

Similarly, one can count the number of triangulations with different properties using the optional arguments.

i4 : topcomNumTriangulations(A, RegularOnly => false)

o4 = 18
i5 : assert(topcomNumTriangulations(A, RegularOnly => false) == 18)
i6 : assert(topcomNumTriangulations(A, RegularOnly => false) == # topcomAllTriangulations(A, RegularOnly => false))

See also

Ways to use this method: