topic Re: FlexSimPy: Performance Measure "TotalProducts" Always Returns 1.0 and None in FlexSim Forum

FlexSimPy: Performance Measure "TotalProducts" Always Returns 1.0 and None

oladosuZ2AY9 — Mon, 14 Apr 2025 21:37:50 GMT

[ FlexSim 24.2.3 ]

Hi all,

I am a student and needed assistance urgently for my project

I'm using FlexSim 2024 integrated with FlexSimPy to extract data after simulation. I’ve set up a Statistics Collector (ProductOutputCount) linked to the Sink (on entry), with Row Value = 1 and a Performance Measure (TotalProducts) referencing it. In the FlexSim GUI, "TotalProducts" correctly shows values like 841 after a simulation run, but when I call

total = controller.getPerformanceMeasure("TotalProducts")

from Python, it always returns 1.0.

I’ve verified that:

The simulation runs and ends correctly.
The global variable/stat mechanism in FlexSim updates as expected.
I've called updateallperfmvalues() from Python prior to reading the performance measure.
All node paths are correct.

Has anyone encountered this issue or can suggest a workaround to force the performance measure to aggregate correctly via FlexSimPy?

Re: FlexSimPy: Performance Measure "TotalProducts" Always Returns 1.0 and None

kavika_faleumu — Tue, 15 Apr 2025 17:17:01 GMT

Hey @max, can you post your model and your python file so we can investigate as to what is happening? Thank you.

Re: FlexSimPy: Performance Measure "TotalProducts" Always Returns 1.0 and None

oladosuZ2AY9 — Tue, 15 Apr 2025 18:34:26 GMT

Thank you for the reply, here are the model and script. test5.py test5.fs.

Re: FlexSimPy: Performance Measure "TotalProducts" Always Returns 1.0 and None

kavika_faleumu — Tue, 15 Apr 2025 21:04:48 GMT

Hey @max, after looking at your python script, everything looks good. It's in the model that the problem is occurring. Your Statistics Collector "ProductOutputCount" is only ever outputing the value "1", no matter how long you run the model. If all you want is the input of the Sink, I suggest you change the Performance Measurement's value to reference the sink's input.

When saved and ran in the Python script, it gives me good values.

If you want to do it through the Statistics Collector anyway, then you may want to look at some of the tutorials we have on different setups for Stats Collectors.

Re: FlexSimPy: Performance Measure "TotalProducts" Always Returns 1.0 and None

oladosuZ2AY9 — Tue, 15 Apr 2025 21:16:31 GMT

You have just resolved my 2 weeks problem, I am so grateful. Please, accept my linkedin request. Thanks