Tim (was: Bill) Peters wrote at 20:45 12/10/2004:
[Dick Moores]
> Aw, that's just amazing.
<Terrific and clear explanation snipped>
> I put your function in http://www.rcblue.com/Python/croots.py,
That's fine by me -- but I'd appreciate it if you stopped claiming
there that my name is Bill <wink>.
Are you sure? Well, OK. Tim it is.
> Actually, I'm trying to write a Python script that computes all 3
> roots of a cubic equation. Do you happen to have one tucked
> away in your store of wisdom and tricks? (One for real coefficients
> will do).
I don't, no. You can code one for cubics from Cardano's formula, e.g.,
http://mathworld.wolfram.com/CubicFormula.html
but it's rarely worth the bother -- it's complicated and doesn't
generalize.
I accept this challenge to write a complicated script of little value.
In practice, roots for polynomials beyond quadratics are
usually obtained by numerical approximation methods that don't care
much about the polynomial's degree.
Are these "numerical approximation methods" pythonically possible?
Dick (AKA George) Moores
[EMAIL PROTECTED]
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