[prev in list] [next in list] [prev in thread] [next in thread] 

List:       kde-core-devel
Subject:    Re: Need help for KSpread Maths
From:       Roberto Alsina <ralsina () unl ! edu ! ar>
Date:       1999-11-18 11:48:12
[Download RAW message or body]

On Thu, 18 Nov 1999, Antonio Larrosa wrote:

> Roberto Alsina wrote:
> > 
> > > I tried some polynomials I couldn't get it stuck in a cubic, which
> > > indicates it has at least some smarts for getting out of/avoiding rel.
> > > extrema. I did manage to get it stuck in a sixth order polynomial
> > > which indicates it isn't that smart. (Numerical solutions for finding
> > > the roots of any (finite) ordered polynomial to arbitrary precision
> > > exist).
> > 
> > Maybe it uses multiple methods?
> > 
> 
> For a general function, IMO, the best thing is to try the Newton method
> and if it doesnīt find anything in a number of steps, then try another
> method that isnīt so fast but is more solid, such as the Regula Falsi one.

Well, Regula Falsi is just a Richardson extrapolation of the numerical
version of Newton, IIRC[1] :-)
 
> If you know the function is a polynomial, then you can use special methods
> to find the roots. Thereīs even the Sturm method that tells you the number
> of roots between two points (without obtaining them).

[1] If I got that right, I'm gonna go back to the uni and get that degree
;-)

 ("\''/").__..-''"`-. .         Roberto Alsina
 `9_ 9  )   `-. (    ).`-._.`)  ralsina@unl.edu.ar
 (_Y_.)' ._   ) `._`.  " -.-'   Centro de Telematica
  _..`-'_..-_/ /-'_.'           Universidad Nacional del Litoral
(l)-'' ((i).' ((!.'             Santa Fe - Argentina
                                KDE Developer (MFCH)
Not mad, but bound more than a madman is (Romeo and Juliet, Act I Scene II)

[prev in list] [next in list] [prev in thread] [next in thread]