Post new topic Reply to topic  [ 2 posts ] 
Author Message
 Post subject: [Q] how to solve and evalutate a polynomial?
PostPosted: Thu Aug 11, 2005 5:32 pm 
if i have a polynomial f (ex : poly f = x2 - 1 )

i want to have f(1) ( f(1) = (1)^2-1 = 0 )
and want to solve f(x) = 0

How can i do this?

email: marine917i@gmail.com
Posted in old Singular Forum on: 2004-10-11 19:23:40+02


Report this post
Top
  
Reply with quote  
 Post subject: Re: [Q] how to solve and evalutate a polynomial?
PostPosted: Thu Aug 11, 2005 8:29 pm 

Joined: Thu Aug 11, 2005 8:03 pm
Posts: 37
Location: RWTH Aachen, Germany
Hi,
Quote:
> if i have a polynomial f (ex : poly f = x2 - 1 )
>
> i want to have f(1) ( f(1) = (1)^2-1 = 0 )
> and want to solve f(x) = 0
>
> How can i do this?

First of all you have define a ring (which includes a definition of a ground field and an ordering on monomials).
In your case let the ground field be Q, then your ring definition will be
Code:
ring r = 0,(x),dp;

Then you define your polynomial.
Code:
poly f = x^2 -1;

For evaluation there is a command "subst"
Code:
poly f1 = subst(f,x,1);

For "solving" you can use either factorization (for one polynomial)
Code:
factorize(f);

or, for systems of equations, see the library "solve.lib".

In any case, you find the detailed information in the documentation, available both on-line (for instance, at http://www.singular.uni-kl.de/Manual/2-0-5/index.htm) and in every distribution you dowload.

Best 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 Mon Dec 11, 2017 10:40 pm
cron
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group