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SRdeformations :: firstOrderDeformation

firstOrderDeformation -- Makes a first order deformation.

Synopsis

Description

Generates a first order deformation ideal mg. If it is given an ideal I then generators of I are stored to have a reference for parameters. You can also give non-minimal generators.

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 : f=firstOrderDeformation(mg, vector {-1,1,0,0,0})

     x
      1
o5 = --
     x
      0

o5 : first order deformation space of dimension 1

See also

Ways to use firstOrderDeformation :

For the programmer

The object firstOrderDeformation is a method function.