How do you know that those are not the right answers? http://en.wikipedia.org/wiki/Wilkinson_polynomial
----- Original Message ----- From: John Randall <[EMAIL PROTECTED]> Date: Sunday, July 27, 2008 14:31 Subject: Re: [Jprogramming] Roots robustness? To: Programming forum <[email protected]> > Sherlock, Ric wrote: > > > I'm wondering whether the point on the wiki page is still > valid and just > > needs a different example, or whether Roots is now robust > enough that the > > warning is no longer required? > > A warning is always required for polynomial roots. If you > could find them > robustly, finding eigenvalues would be a lot easier. > > I agree that the page no longer demonstrates the point. > However, consider > this (note line wrap): > > roots=: >@(1&{)@p. > roots p. 1;(i.20),20 > 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 > roots p. 1;(i.20),20.0001 > 19.0022j9.43931e_25 19.0022j_9.43931e_25 18.0078j5.55694e_15 > 18.0078j_5.55694e_15 16.1666j2.13971e_20 16.1666j_2.13971e_20 > 12.6895j0.0771052 12.6895j_0.0771052 12.5845 10.8835 10.05 > 8.98704 8.00238 > 6.99968 6.00002 5 4 3 2 1 0 ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
