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D.6.13.18 spsemicont

Procedure from library gmssing.lib (see gmssing_lib).

Usage:
spsemicont(sp0,sp,k[,1]); list sp0, list sp

Return:
 
list l;
  intvec l[i];  if the spectra sp0 occur with multiplicities k
                in a deformation of a [quasihomogeneous] singularity
                with spectrum sp then k<=l[i]

Example:
 
LIB "gmssing.lib";
ring R=0,(x,y),ds;
list sp0=list(ideal(-1/2,-3/10,-1/10,0,1/10,3/10,1/2),intvec(1,2,2,1,2,2,1));
spprint(sp0);
==> (-1/2,1),(-3/10,2),(-1/10,2),(0,1),(1/10,2),(3/10,2),(1/2,1)
list sp1=list(ideal(-1/6,1/6),intvec(1,1));
spprint(sp1);
==> (-1/6,1),(1/6,1)
list sp2=list(ideal(-1/3,0,1/3),intvec(1,2,1));
spprint(sp2);
==> (-1/3,1),(0,2),(1/3,1)
list sp=sp1,sp2;
list l=spsemicont(sp0,sp);
l;
==> [1]:
==>    3
==> [2]:
==>    2,1
spissemicont(spsub(sp0,spmul(sp,l[1])));
==> 1
spissemicont(spsub(sp0,spmul(sp,l[1]-1)));
==> 1
spissemicont(spsub(sp0,spmul(sp,l[1]+1)));
==> 0