Non linear equations: howto?

Fabrice DELENTE fdelente at mail.cpod.fr
Sun Oct 19 10:29:10 CDT 2008


On Sun, Oct 19, 2008 at 05:17:45PM +0200, Søren Hauberg wrote:
> If you're equation has many solutions, then fsolve will essentially find
> the one closest to the initial guess.

Thought so.

> I'm curious: f is a function of 5 parameters, so how do you plot it?

In fact f is just a function of x, and I plot y=f(x).

The parameters are there so that f's curve goes through the points I want.

So a,b,c,d and e should have the right values so that f's curve goes through
(1,0), (2,2) etc. as I said in my first post.

My problem is that I have the curve of f, and I'd like to find its equation;
I guessed that f is of the form (a*x+b)*exp(c*x+d)+e, and I'm trying to find
the right values for a,b,c,d and e.

I tried solving algebraically with maxima, but didn't get an answer, so I
turned to numerical solving.

-- 
Fabrice DELENTE


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