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D.6.13.3 jacoblift

Procedure from library mondromy.lib (see mondromy_lib).

Usage:
jacoblift(f); f poly

Assume:
The polynomial f in a series ring (local ordering) defines an isolated hypersurface singularity.

Return:
The procedure returns a list with entries kappa, xi, u of type int, vector, poly such that kappa is minimal with f^kappa in jacob(f), u is a unit, and u*f^kappa=(matrix(jacob(f))*xi)[1,1].

Display:
The procedure displays comments if printlevel>=1.

Example:
 
LIB "mondromy.lib";
ring R=0,(x,y),ds;
poly f=x2y2+x6+y6;
jacoblift(f);
==> [1]:
==>    2
==> [2]:
==>    1/2x2y3*gen(2)+1/6x7*gen(1)+5/6x6y*gen(2)-2/3xy6*gen(1)+1/6y7*gen(2)-4\
   x4y5*gen(2)-3/2x9y2*gen(1)-15/2x8y3*gen(2)+9/2x3y8*gen(1)-3/2x2y9*gen(2)
==> [3]:
==>    1-9x2y2