[...]

Quote:> d*(1 - x/e)**2

[...]

> Isn't it possible however to give a best fit directly to the first

> equation?

It is, but it's considerably harder. The problem is that the

dependence of this functions on its parameters is quite non-linear,

and the parameters are strongly anti-correlated.

This means you'll probably need startup values for the parameters, and

that they will have to be at least vaguely in the right size, or the

fit will refuse to converge, or kick either of the parameters all the

way off to Alpha Centauri.

On top of all that, the function you compared that fit to:

Quote:> However fitting first to a*x**2 + b*x + c

has *three* parameters, whereas the one above has only two, so it's

less flexible by design. This makes your comparison rather

unrealistic.

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Even if all the snow were burnt, ashes would remain.