Re: What to give as "real column vector of initial parameters" to nonlin_curvefit?

[Dmitri A. Sergatskov]

On Thu, Jun 11, 2020 at 9:04 AM Doron Behar <doron.behar@gmail.com> wrote:

Hey dear octaves,

So today I wanted to fit a curve to a set of x and y data and I reached
the nonlin_curvefit function. Docs:
https://octave.sourceforge.io/optim/function/nonlin_curvefit.html

What am I supposed to give the 2nd argument? It seems like a necessary
argument according to the signature. The docs don't explain much about
it and I haven't found much in the mailing list's archives.

I tried to take the example and fiddle with the values they give there
and I haven't noticed any change in the final plots of the data vs the
fit...

Thanks.

Initial guess for the fit parameters. E.g. if you are fitting to say a*sin(x) + b*cos(x), then pin is  [a0, b0].

If you do not know what a0 and b0 could be,  set them to 1.

Dmitri.

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