Constrained optimization does not terminate (stopping criteria are ignored)

[ghighuphu]

Dear dev and users,

the "constrained nonlinear optimization" in my program won't terminate. Limiting the calculation time (<1s) or the number of iterations (<300) or other "stopping criteria" does not help. The process hangs on for tens minutes (I kill it finally). The input data are nothing special compared to the other hundreds previously processed successfully. I processed my data set (600 data) and it hanged twice at different data. What other information shall I supply, so I could get some help from you, please?

Thank you for listening.

Cheers,

M

[altenbach]

The code might be hanging inside the model or in some other subVI.

Can you provide a bit more detail on the type of the polymorphic instance and model type you are using?

Would it be possible for you to attach a small sample VI containing data that shows the problem?

[ghighuphu]

Dear altenbach,

Unfortunately I cannot post my objective function. But a solution was found: The "function tolerance" in the "stopping criteria" was too low, and the isisubopt.vi kept running increasing some values to Inf and never ending a loop.

I corrected my stopping criteria, after I followed the hints at a different topic here, and troubleshooted the isisubopt.vi:
http://forums.ni.com/t5/LabVIEW/Using-Constraints-on-my-optimization-problem-currently/m-p/1941655/h...

Cheers,
M

[sassyaspy]

Hello,

The hanging behavior of the Unconstrained Nonlinear Optimization VI was tracked by CAR 401689 has been fixed in LabVIEW 2015. Under certain conditions we used to get into an infinite loop in the VI, as you had seen in your program. There are now good checks in place to make sure that in the case of infinite values we stop the function and return an error.