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)
 -- .0126207s elapsed
 -- .0178526s elapsed
(number Of blocks, 26)
 -- .000320959s elapsed
1
 -- .000132406s elapsed
1
 -- .000125042s elapsed
1
 -- .000131536s elapsed
1
 -- .000121917s elapsed
2
 -- .000127858s elapsed
 2
2
 -- .000147395s elapsed
 2
2
 -- .000152324s elapsed
 2
2 3
 -- .000142617s elapsed
 2
2 3
 -- .000127899s elapsed
 2
2 3
 -- .000125735s elapsed
 2
2
 -- .000162142s elapsed
 2
2
 -- .000130022s elapsed
2
 -- .000120365s elapsed
2
 -- .000139882s elapsed
 2
2
 -- .000127628s elapsed
 2
2
 -- .00314453s elapsed
 2
2 3
 -- .000136104s elapsed
 2
2 3
 -- .00014516s elapsed
 2
2 3
 -- .000127949s elapsed
 2
2
 -- .000136664s elapsed
 2
2
 -- .000133609s elapsed
2
 -- .000119704s elapsed
1
 -- .000157052s elapsed
1
 -- .000125524s elapsed
1
 -- .000135123s 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/reproducible-path/macaulay2-1.26.06+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