euler(CoherentSheaf) -- Euler characteristic of coherent sheaf

Synopsis

• Function: euler

• Usage:

  euler F

• Inputs:
  • F, a coherent sheaf
• Outputs:
  • an integer, the Euler characteristic of the cohomology of the sheaf

Description

The command returns chi(F) the Euler characteristic of the sheaf F i.e. the alternated sum of the dimensions of its cohomology groups

See also

• eulers(CoherentSheaf) -- list the sectional Euler characteristics
• genus -- arithmetic genus