MultiStart runs less than specified number of runs

I use the command

run(ms,problem,n)

with n=20. But it runs smaller number of "runs" than 20. I tried it many times, and at each of them that number is different. For example,

MultiStart completed the runs from all start points.

All 7 local solver runs converged with a positive local solver exit flag.

or

MultiStart completed some of the runs from the start points.

4 out of 5 local solver runs converged with a positive local solver exit flag.

These two different outputs are for the exact same problem with n=20. I guess it somehow optimizes the number of runs, or somehow finds out there's no need to run the remaining ones. But I want to know what's really going on and I believe there should be a way to force it to run all the given "number of runs", which is n=20, here.

Answer 1

[Alan Weiss]

This can happen when the StartPointsToRun property in ms is not 'all'. In that case, many start points can be skipped in a run because they do not satisfy the bounds or bounds and inequalities.

There may be other reasons. To get more information from us, provide more information, such as your exact problem setup, how you create ms, and what its properties are.

Alan Weiss

MATLAB mathematical toolbox documentation