Singular

LIB "polyclass.lib";
ring R=(0,a),(x,y,z,w),ds;
minpoly = a^2-2;
Poly f=x^4+x^2*y^2+a*y^8+z^2-w^2;
NormalFormEquation F;
F.vars = ringlist(R)[2];
F.realCase = 1;
F.normalFormEquation = f;
F.modality = 1;
F.corank = 2;
F.inertiaIndex = 1;
F.determinacy = 8;
F.milnorNumber = milnor(f.value);
F.parameters = list(list(a*y^8,list(0,2)));
F.singularityType = "X[13]";
F;
==> Corank = 2
==> Inertia index = 1
==> Normalform equation of type = X[13]
==> Normalform equation = z2-w2+x4+x2y2+(a)*y8
==> Milnor number = 13
==> Modality = 1
==> Parameter term = (a)*y8
==> Minimal polynomial = (a2-2)
==> Interval = [0, 2]
==> Determinacy <= 8
==> 
ring R=(0),(x,y,z,w),ds;
==> // ** redefining R (ring R=(0),(x,y,z,w),ds;) ./examples/printNormalFormE\
   quation.sing:17
Poly f=x^4+x^2*y^2+7*y^8+z^2-w^2;
==> // ** redefining f (Poly f=x^4+x^2*y^2+7*y^8+z^2-w^2;) ./examples/printNo\
   rmalFormEquation.sing:18
NormalFormEquation F;
==> // ** redefining F (NormalFormEquation F;) ./examples/printNormalFormEqua\
   tion.sing:19
F.vars = ringlist(R)[2];
F.realCase = 1;
F.normalFormEquation = f;
F.modality = 1;
F.corank = 2;
F.inertiaIndex = 1;
F.determinacy = 8;
F.milnorNumber = milnor(f.value);
F.parameters = list(list(7*y^8,list(-6,8)));
F.singularityType = "X[13]";
F;
==> Corank = 2
==> Inertia index = 1
==> Normalform equation of type = X[13]
==> Normalform equation = z2-w2+x4+x2y2+7y8
==> Milnor number = 13
==> Modality = 1
==> Parameter term = 7y8
==> Determinacy <= 8
==>