From: "John D'Errico" <woodchips@rochester.rr.com>
Path: news.mathworks.com!newsfeed-00.mathworks.com!webcrossing
Newsgroups: comp.soft-sys.matlab
Subject: Re: fitting data to an integral
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Date: Sat, 10 Mar 2007 04:36:38 -0500
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B.K. Chen wrote:
>
>
> Hi , all,
>
> I have a set of data points to be fitted to an equation,but
> this
> equatin contains an integral sign(it's
> not analytic). I cannot find any way to fit my data to an
> integral equation in Matlab. Does somebody have ideas about this
> issue? If yes,please let me know!
  

A lot depends on the equation itself
and what is under the integral. Many
integrals exist as special functions.
(erf, elliptic functions, incomplete
beta function, etc.) Don't be put off
by my response. MANY people post
exactly this question when their
integrand is as simple as exp(-x^2).
They simply have not looked very hard
for the answer.

If their really is no solution available
in the form of a special function, then
quad is an option, called from within
your objective function. Or splines
(often coupled with regularization)
can be used when no explicit form is
known.

So without any knowledge of your
problem, I cannot suggest how to
solve it.

John