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Macaulay2Doc :: genus(CoherentSheaf)

genus(CoherentSheaf) -- arithmetic genus

Synopsis

Description

Computes the arithmetic genus of the coherent sheaf F that is (-1)^dim-support * (chi(F) - 1)). If F is a module over a ring, then the genus of F~ is computed. If I is an ideal in a ring R then the genus of (R/I)~ is computed.
i1 : V = Proj(QQ[x,y,z]/ideal(y^2*z-x^2*(x+z)))

o1 = V

o1 : ProjectiveVariety
i2 : genus OO_V^1

o2 = 1

See also