[Numpy-discussion] roots and high-order polynomial

[Dag Sverre Seljebotn]

Fabrice Silva wrote:
> Le vendredi 03 juillet 2009 à 11:52 +0200, Nils Wagner a écrit :
>> You will need multiprecision arithmetic in that case.
>> It's an ill-conditioned problem.
> 
> I may have said that the solution are of the same order of magnitude, so
> that the ratio between the lowest and the highest absolute values of the
> eigenvalues are rather close to one.
> Does it help ?
> 
> Looking in the debian repository, I found python-gmpy, an interface GMP
> to Python. But how could it be used to compute the eigenvalues of the
> companion matrix ? I will look in the doc...
> 

One of the easiest ways to calculate with GMP and similar, with Python, 
is with Sage:

http://www.sagemath.org

Finding the roots of a polynomial should be very natural within Sage.

-- 
Dag Sverre