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FirstOrderDeformation == FirstOrderDeformation -- Compare two first order deformations.

Synopsis

Description

Checks whether f1 and f2 are equal.

i1 : R=QQ[x_0..x_4];
i2 : addCokerGrading(R)

o2 = | -1 -1 -1 -1 |
     | 1  0  0  0  |
     | 0  1  0  0  |
     | 0  0  1  0  |
     | 0  0  0  1  |

              5       4
o2 : Matrix ZZ  <-- ZZ
i3 : I=ideal(x_0*x_1,x_1*x_2,x_2*x_3,x_3*x_4,x_4*x_0)

o3 = ideal (x x , x x , x x , x x , x x )
             0 1   1 2   2 3   3 4   0 4

o3 : Ideal of R
i4 : mg=mingens I;

             1      5
o4 : Matrix R  <-- R
i5 : f1=firstOrderDeformation(mg, vector {-1,1,0,0,0})

     x
      1
o5 = --
     x
      0

o5 : first order deformation space of dimension 1
i6 : f2=firstOrderDeformation(mg, vector {0,2,0,-1,-1})

       2
      x
       1
o6 = ----
     x x
      3 4

o6 : first order deformation space of dimension 1
i7 : f2==f2

o7 = true
i8 : f2==f1

o8 = false

Ways to use this method: