charts -- the number of maximal affine charts

Synopsis

• Usage:

  n = charts E

• Inputs:
  • E, an instance of the type ToricVectorBundle
• Outputs:
  • n, an integer

Description

The function charts returns the number of maximal cones in the underlying fan, i.e., the number of affine charts.

i1 : E = cotangentBundle pp1ProductFan 3

o1 = {dimension of the variety => 3 }
      number of affine charts => 8
      number of rays => 6
      rank of the vector bundle => 3

o1 : ToricVectorBundleKlyachko

i2 : charts E

o2 = 8

See also

• Fan -- the class of all fans
• fan(ToricVectorBundle) -- the underlying fan of a toric vector bundle