How do I set a custom algebraic upper/lower bound on lsqcurvefit, instead of a constant one?

How do I set a custom algebraic upper/lower limit on lsqcurvefit, instead of a constant one? On lsqcurvefit, I can only specify a constant value as upper/lower bound, but I want to set an algebraic expression, such as (y ~ b0*x1+b1*x2) where b0+b1<1

Answer 1

[Alan Weiss]

For that, you will have to use lsqlin (if it is applicable) or fmincon if it is not applicable. I cannot be sure, based on your description, whether lsqlin applies.

Alan Weiss

MATLAB mathematical toolbox documentation

[Samuel Castro]

Thanks Alan, I gave a linear example, but the function I want to fit will most likely be non linear. So I would need to define a a fmincon function reducing the quadratic error of it?

[Alan Weiss]

Yes, you would. See this example, which uses fminunc, but you can easily adapt it to fmincon.

Alan Weiss

MATLAB mathematical toolbox documentation