Post new topic Reply to topic  [ 2 posts ] 
Author Message
 Post subject: It is possible to an ideal contain fractions?
PostPosted: Thu Aug 11, 2005 5:31 pm 
Can an ideal contain fractions? Moreover, what does singular with the following input:

ring R=0,(x,y,z,w),dp;
ideal I=x^2+y-w,(x^2+z)/(1-y-z^2),(x^3-y)/(x+y+z+w);
std(I);



email: [email protected]
Posted in old Singular Forum on: 2002-12-20 18:43:57+01


Report this post
Top
  
Reply with quote  
 Post subject: Re: It is possible for an ideal to contain fractions?
PostPosted: Thu Aug 11, 2005 8:55 pm 

Joined: Thu Aug 11, 2005 8:03 pm
Posts: 40
Location: RWTH Aachen, Germany
Quote:
> Can an ideal contain fractions?

No. Fractions are not elements of the ring of polynomials (but of the field of rational functions).

Quote:
>Moreover, what does singular with the following input:
>
Code:
ring R=0,(x,y,z,w),dp;
ideal I=x^2+y-w,(x^2+z)/(1-y-z^2),(x^3-y)/(x+y+z+w);
std(I);


The division is performed in the ring of polynomials giving zero as the second and the third generators of I.

If you want to solve the system of equations
x^2+y-w = 0,
x^2+z = 0,
x^3-y = 0,
1-y-z^2 <> 0,
x+y+z+w <> 0,
we recommend the following:
Code:
ring R=0,(x,y,z,w),dp;
ideal I = x^2+y-w,x^2+z,x^3-y;
ideal J = 1-y-z^2, x+y+z+w;
facstd(I,J);


See the description of facstd for details.

Regards,

_________________
Viktor Levandovskyy


Report this post
Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

You can post new topics in this forum
You can reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

It is currently Fri May 13, 2022 10:57 am
cron
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group