At 07:58 AM 5/24/2008, Duncan Murdoch wrote:
Shubha Vishwanath Karanth wrote:
To apply uniroot I don't even know the interval values... Does
numerical methods help me? Or any other method?
I forgot: we also have polyroot().
Duncan Murdoch
Thanks and Regards,
Shubha
-----Original Message-----
From: Duncan Murdoch [mailto:[EMAIL PROTECTED] Sent: Saturday,
May 24, 2008 5:08 PM
To: Shubha Vishwanath Karanth
Subject: Re: [R] Solving 100th order equation
Shubha Vishwanath Karanth wrote:
Hi R,
I have a 100th order equation for which I need to solve the value
for x. Is there a package to do this?
<snip>
Finding all of the roots of a 100-th order polynomial on a computer
is not an easy task. It would take move than 100 digits of precision
to do so. A similar problem to finding all 100 eigenvalues of a
100x100 ill-conditioned matrix.
The suggestion to use graphics to find small intervals localizing the
roots of interest first would make the most sense, at least for the real roots.
It is highly unlikely that all 100 roots are needed. Usually the ones
of interest are the one with the largest real part, or the ones
inside the unit circle, or the real roots, etc.
Is this a homework problem?
================================================================
Robert A. LaBudde, PhD, PAS, Dpl. ACAFS e-mail: [EMAIL PROTECTED]
Least Cost Formulations, Ltd. URL: http://lcfltd.com/
824 Timberlake Drive Tel: 757-467-0954
Virginia Beach, VA 23464-3239 Fax: 757-467-2947
"Vere scire est per causas scire"
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
