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 0.506826s (cpu); 0.365897s (thread); 0s (gc)

       3
o3 = 4h
       1

     ZZ[h ]
         1
o3 : ------
        5
       h
        1

i4 : time CSM(I,InputIsSmooth=>true)
 -- used 0.11412s (cpu); 0.0527337s (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 0.0559861s (cpu); 0.030652s (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 /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/CharacteristicClasses.m2:2500:0.