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InputIsSmooth

Description

The option InputIsSmooth is only used by the commands CSM, and Euler. If the input ideal is known to define a smooth subscheme setting this option to true will speed up computations (it is set to false by default).

i1 : R = ZZ/32749[x_0..x_4];
i2 : I=ideal(random(2,R),random(2,R),random(1,R));

o2 : Ideal of R
i3 : time CSM I
 -- used 0.684168s (cpu); 0.527812s (thread); 0s (gc)

       3
o3 = 4h
       1

     ZZ[h ]
         1
o3 : ------
        5
       h
        1
i4 : time CSM(I,InputIsSmooth=>true)
 -- used 0.0516331s (cpu); 0.0446455s (thread); 0s (gc)

       3
o4 = 4h
       1

     ZZ[h ]
         1
o4 : ------
        5
       h
        1

Note that one could, equivalently, use the command Chern instead in this case.

i5 : time Chern I
 -- used 0.0494859s (cpu); 0.0416387s (thread); 0s (gc)

       3
o5 = 4h
       1

     ZZ[h ]
         1
o5 : ------
        5
       h
        1

Functions with optional argument named InputIsSmooth:

  • CSM(...,InputIsSmooth=>...) -- see CSM -- The Chern-Schwartz-MacPherson class
  • Euler(...,InputIsSmooth=>...) (missing documentation)

For the programmer

The object InputIsSmooth is a symbol.


The source of this document is in CharacteristicClasses.m2:2463:0.