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SOLVE in ideal 1-dimensional

SOLVE in ideal 1-dimensional

vpachecu2 · Mon Mar 29, 2010 4:40 pm

hello friends

i need to compute solutions of a ideal that dont are 0-dimensional
in the examples, its uses the function std.
but in my case
even after using the command, the dimension of the ideal remains the same
and must reduce it to 0 to use the function solve, or need one that returns a solution to an ideal that is not 0-dimensional

ideal s= x(1)^2+(5.072659+i*1.481763)*x(1)-75;
when i use std(s), its return the same s.

i need that dim(s) be a 0
or solve s with other funcion

Re: SOLVE in ideal 1-dimensional

gorzel · Mon Mar 29, 2010 7:24 pm

Your ideal is definitely zero-dimensional.

Tell us, how does your basering looks like?

I suppose that you defined a ring with several variables.

Singular computes the dimension with respect to the
ambiant ring you are working in and not with respect to
the number of variables that occur in the ideal.

So define a new ring only in the variable x(1) and fetch the
ideal s to this ring.Then call solve again. This should then work.

Re: SOLVE in ideal 1-dimensional

vpachecu2 · Mon Mar 29, 2010 7:36 pm

> basering;
// characteristic : 0 (complex:6 digits, additional 6 digits)
// 1 parameter : i
// minpoly : (i^2+1)
// number of vars : 2
// block 1 : ordering lp
// : names x(1) x(2)
// block 2 : ordering C

Re: SOLVE in ideal 1-dimensional

gorzel · Mon Mar 29, 2010 11:43 pm

And did you try what I proposed?

Actually, I think your ring definition was

Code:
ring R = complex,(x(1..2)),dp;

Now define
Code:
ring Rnew = complex,(x(1)),dp;
ideal s = imap(R,s);
// ideal s= x(1)^2+(5.072659+i*1.481763)*x(1)-75;
solve(s);  // from solve.lib

Re: SOLVE in ideal 1-dimensional

vpachecu2 · Mon Apr 05, 2010 4:32 pm

HELlo

thanks, this really solved my problem



gorzel wrote:
And did you try what I proposed?

Actually, I think your ring definition was

Code:
ring R = complex,(x(1..2)),dp;

Now define
Code:
ring Rnew = complex,(x(1)),dp;
ideal s = imap(R,s);
// ideal s= x(1)^2+(5.072659+i*1.481763)*x(1)-75;
solve(s);  // from solve.lib