Simulations not repeatable

NoePanier 4 years ago in IQANsimulate updated by Gustav Widén (System support) 4 years ago 3


I have been trying to validate some modifications I made on IQAN Design 6.02 with IQAN Simulate 6 but I realized that the simulations were not constant.

I tried to run a Simulation groups on two identicalDesign I copy/pasted so there could be no difference due to data stored but even with that, the data I got from the two simulations were not exactly the same. Usually, both would be very similar, but one would be 50 to 500 ms late from the other, or even sometime skip a data so when I make a checksum of the Mesure group's values in Excel, my results are not the same.

I was wondering if I was doing something wrong or if there was a way to fix it because I would have to validate more modifications like that and it doesn't feel right to have to play with the data to make them fit..

Thanks you.


promt and really helpfull reply!

Satisfaction mark by NoePanier 4 years ago

I sounds as if you have simulation groups with signal generators to control the input to the simulation? 

And it sounds as if you are recording the data via a measure group graph measure in either IQANdesign or IQANrun? Probably IQANdesign, as the graph measure can be started automatically by pressing the simulate play button from within IQANdesign. 

If you add a ms TMR to the measure group, you should be able to observe how the first sampled time will vary some, and you'd probably see how the timer value in the graph measure skips a cycle from time to time. 

For a more repeatable result, you can try stepping through the simulation instead, by manually stepping you allow the PC time to complete the measure operation between each cycle. 

A more elaborate method would be to use the IQANsimulate API to step from another program. 

If you choose to step through a simulation of a multi-master system, be aware that the step button steps is one cycle for each master, regardless of cycle time. With different cycle times you will see different timer values. 



Thanks you for your quick response.

Indeed, you guessed it right for my current simulating method.

I tried with the stepping and it works fine, will only need to find a way to automate the stepping process through IQANsimulate and I will be good to go.

Thanks again and have good day


Thanks. What you can try to do is to automate the stepping via the IQANsimulate ActiveX API.