carpetDet -- compute the determinant of the crucial constant strand of a carpet X(a,b)

Usage:

d = carpetDet(a,b)
Inputs:
- a, an integer, the larger value, i.e a>=b
- b, an integer, the desired clifford index
Outputs:
- d, an integer, the crucial determinant

Description

We compute nonminimal resolution F of the carpet of type (a,b) over a finite prime field, Lift this to a resolution over ZZ, introduce the fine grading, grep the various blocks of the crucial map in the a-th strand, compute their determinants and return their product.

i1 : a=4,b=4

o1 = (4, 4)

o1 : Sequence

i2 : d=carpetDet(a,b)
 -- .00672111s elapsed
 -- .012161s elapsed
(number Of blocks, 26)
 -- .000209122s elapsed
1
 -- .000137531s elapsed
1
 -- .00013185s elapsed
1
 -- .000136482s elapsed
1
 -- .000129871s elapsed
2
 -- .000155802s elapsed
 2
2
 -- .000149481s elapsed
 2
2
 -- .000162022s elapsed
 2
2 3
 -- .00013717s elapsed
 2
2 3
 -- .000136031s elapsed
 2
2 3
 -- .000126813s elapsed
 2
2
 -- .000157442s elapsed
 2
2
 -- .000121851s elapsed
2
 -- .000124361s elapsed
2
 -- .000125841s elapsed
 2
2
 -- .000122821s elapsed
 2
2
 -- .000134531s elapsed
 2
2 3
 -- .000134531s elapsed
 2
2 3
 -- .00014051s elapsed
 2
2 3
 -- .000161642s elapsed
 2
2
 -- .000127441s elapsed
 2
2
 -- .000123921s elapsed
2
 -- .000122362s elapsed
1
 -- .000146902s elapsed
1
 -- .000125151s elapsed
1
 -- .000123241s elapsed
1

o2 = 3131031158784

i3 : factor d

      32 6
o3 = 2  3

o3 : Expression of class Product

Ways to use carpetDet:

carpetDet(ZZ,ZZ)

For the programmer

The object carpetDet is a method function.

The source of this document is in /build/macaulay2-tiVLjc/macaulay2-1.25.11+ds/M2/Macaulay2/packages/K3Carpets.m2:1335:0.

carpetDet -- compute the determinant of the crucial constant strand of a carpet X(a,b)

Description

See also

Ways to use carpetDet:

For the programmer