what does MaxFunEvals mean?

I use fminunc to find local optimum of a function and get a warning: "fminunc stopped because it exceeded the function evaluation limit, options.MaxFunEvals = 3600 (the default value)."

I know how to set options.MaxFunEvals, but I don't know what's the meaning of this parameter? The description in the document is "Maximum number of function evaluations allowed".

From my understanding, the termination parameter includes max number of iteration, change of step size, change of function value, change of gradient and so on. But I have no idea what "Maximum number of function evaluations allowed" means.

Answer 1

[Star Strider]

It’s the maximum number of times the routine evaluates your objective function, each time with the updated parameter estimates.

[Wang]

Thanks for the answer! Then what's the difference between it and the maximal number of iteration?

[Star Strider]

My pleasure!

The maximum number of iterations are the iterations of the fminunc function itself.