search

jakobkroeker / test_singular

manage a personal issue list for Singular CAS
0 stars 0 forks source link

preimage issue #218

Open jakobkroeker opened 9 years ago

jakobkroeker commented 9 years ago

here a smal example from normalP

LIB("normal.lib");
ring rng = (41),(x(1),x(2),x(3)),(dp(3),C);
short = 0 ;
intvec op = 130,16787537;
 option(set, op) ;
 option() ;
//options: redSB redThrough redefine loadLib usage prompt warn
ideal J =7*x(2)^2*x(3)-13*x(1)*x(3)^2+4*x(1);
def normalResult = normalP(J);

for greater characteristic the memory consumption grows

corresponding preimage issue:

ring R = 41,(x,y,z),dp;

ideal F = y^2*z+4*x*z^2-17*x;
F = std(F);
qring Q = F;

map phi = Q, x^41,y^41,z^41;
ideal I = y^41,y^2*z+4*x*z^2-17*x;

preimage(Q, phi ,I);

asked Hans and Gerhard, if something can be improved for this class of examples