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IsGraded -- an option used by numerous functions which tells it to treat the divisors as if we were working on the Proj of the ambient ring.

Description

An option used by numerous functions which tells it to treat the divisors as if we were working on the Proj of the ambient ring. In other words, setting it to true tells the function to ignore behavior at the irrelevant ideal (the ideal generated by vars Ring). Default value is false.

Functions with optional argument named IsGraded:

  • canonicalDivisor(...,IsGraded=>...) -- see canonicalDivisor -- compute a canonical divisor of a ring
  • divisor(...,IsGraded=>...) -- see divisor -- constructor for (Weil/Q/R)-divisors
  • embedAsIdeal(...,IsGraded=>...) -- see embedAsIdeal -- embed a module as an ideal of a ring
  • isCartier(...,IsGraded=>...) -- see isCartier -- whether a Weil divisor is Cartier
  • isLinearEquivalent(...,IsGraded=>...) -- see isLinearEquivalent -- whether two Weil divisors are linearly equivalent
  • isPrincipal(...,IsGraded=>...) -- see isPrincipal -- whether a Weil divisor is globally principal
  • isQCartier(...,IsGraded=>...) -- see isQCartier -- whether m times a divisor is Cartier for any m from 1 to a fixed positive integer n1.
  • isQLinearEquivalent(...,IsGraded=>...) -- see isQLinearEquivalent -- whether two Q-divisors are linearly equivalent
  • isSmooth(Ideal,IsGraded=>...) -- see isSmooth(Ideal) -- whether R mod the ideal is smooth
  • isSNC(...,IsGraded=>...) -- see isSNC -- whether the divisor is simple normal crossings
  • nonCartierLocus(...,IsGraded=>...) -- see nonCartierLocus -- the non-Cartier locus of a Weil divisor
  • ramificationDivisor(...,IsGraded=>...) -- see ramificationDivisor -- compute the ramification divisor of a finite inclusion of normal domains or a blowup over a smooth base

For the programmer

The object IsGraded is a symbol.


The source of this document is in Divisor.m2:2057:0.