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A question

A question

Hossein Movasati · Thu Aug 11, 2005 5:32 pm

Dear all
I do not get answer form the following simple commands.

int d=3;
ring r=0,(x(1..5), x(0)), lp;
poly g=x(1)^(d+1)+x(2)^(d+1)+x(3)^(d+1)+x(4)^(d+1)+x(5)^(d+1);
poly f=g-(x(1)+x(2)+x(3)+x(4)+x(5))*x(0)^d-x(0)^(d+1);
ideal V=kbase(groebner(jacob(f)));
V;
I have wited for more than one day but no answer.

-----------------------
Hossein Movasati
Mathematisches Institut
Georg-August-Universtaet
Bunsenstr. 3-5
37073 Goettingen
Tel: 0049-551-397796 Office, 7895877 Home
Email: movasati@uni-math.gwdg.de
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email: movasati@uni-math.gwdg.de
Posted in old Singular Forum on: 2004-05-13 11:29:06+02

Re: A question (on groebner command)

levandov · Thu Aug 11, 2005 8:34 pm

Dear Hossein Movasati,

Quote:
Dear all
I do not get answer form the following simple commands.

int d=3;
ring r=0,(x(1..5), x(0)), lp;
poly g=x(1)^(d+1)+x(2)^(d+1)+x(3)^(d+1)+x(4)^(d+1)+x(5)^(d+1);
poly f=g-(x(1)+x(2)+x(3)+x(4)+x(5))*x(0)^d-x(0)^(d+1);
ideal V=kbase(groebner(jacob(f)));
V;
I have waited for more than one day but no answer.


First of all, the K-dimension of groebner(jacob(f)) is 729 (use the command "vdim"). At our PCs it has been computed in several seconds.

What kind of PC do you have? Which version of Singular do you use
(execute "Singular -v")?

In general, for non-trivial examples, we recommend to split nested commands into a sequence:

Code:
poly f=g-(x(1)+x(2)+x(3)+x(4)+x(5))*x(0)^d-x(0)^(d+1);
option(prot); // to see what's going on
ideal I=groebner(jacob(f));
ideal V=kbase(I);


With best regards, [/quote]