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D.6.10.4 WSemigroup

Procedure from library curvepar.lib (see curvepar_lib).

Usage:
WSemigroup(X,b0);
X a list of polynomials in one variable, say t.
b0 an integer

Compute:
Weierstrass semigroup of space curve C,which is given by a parametrization X[1](t),...,X[k](t), till the bound b0.

Assume:
b0 is greater then conductor

Return:
list M of size 5.
M[1]= list of integers, which are minimal generators set of the Weierstrass semigroup. M[2]=integer, conductor of the Weierstrass semigroup. M[3]=intvec, all elements of the Weierstrass semigroup till some bound b, which is greater than conductor.

Warning:
works only over the ring with one variable with ordering ds

Example:
 
LIB "curvepar.lib";
ring r=0,(t),ds;
list X=t4,t5+t11,t9+2*t7;
list L=WSemigroup(X,30);
L;
==> [1]:
==>    4,5,7
==> [2]:
==>    7
==> [3]:
==>    4,5,7,8,9,10