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SRdeformations :: parameters

parameters -- Parameters of a deformation.

Synopsis

Description

Computes a matrix whose columns correspond to the parameters of f (i.e., to the coefficients of the images of the generators of source(FirstOrderDeformation) f considering it as a homomorphism.

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

              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
i6 : relationsCoefficients f

o6 = | -1 |
     | 1  |

              2        1
o6 : Matrix ZZ  <--- ZZ
i7 : parameters f

o7 = | 0 |
     | 1 |
     | 0 |
     | 0 |
     | 1 |

              5        1
o7 : Matrix ZZ  <--- ZZ

See also

Ways to use parameters :

For the programmer

The object parameters is a method function.