Re: Matlab optimization question

"anja.ende@xxxxxxxxxxxxxx" <anja.ende@xxxxxxxxxxxxxx> wrote in
message <9841aed9-8df4-471b-b159-
8fd97a33e5d6@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>...
Hi everyone,

I need some help regarding optimization and data-fitting. It has to do
with finding some coefficients that minimizes a function but I am
unable to find a good way to start.

I have a data file that contains some time points and a variable that
evolves with time.

I have a function as follows:

c = 0.07 * (exp(t - x1) / 3.4 - x2)

c is known for a set of time (t) points and the task is to find x1 and
x2 with the constraint that t > x1.

Can I formulate this as an optimization problem and use something like
fmincon to solve this?

All the examples that I see, do not show how to pipe the input data (c
and t arrays in my case)?

Also, how can I specify the constraint which involves one of the
unknown variables (x1)?

I hope I have expressed the problem clearly enough...
Thanks,
Anja

Use lsqcurvefit or lsqnonlin. The constraint is
a simple bound constraint. Or you could use a
function like easyfit from the file exchange.

John
.

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