Simulink Stop Time from External Input

Hi everyone, I have a relatively simple question but cannot find the answer.

I want to run several hundred simulations from pregenerated data using parsim.

The generated signals are stored as Timeseries in a Dataset Ref object. The signals all have very different length in time, as this depends on the signal characteristics.

Is there any way to have my model derive the StopTime parameter from the input TimeSeries at simulation time? How would I set this up?

Answer 1

[Jon]

You can run simulation models programatically using the sim command. You can get the documentation for that by typing doc sim on your MATLAB command line. This allows you to specify name, value pairs. so for example

tStop = 30; % you could have additional code to determine stop time
simout = sim('myModel','StopTime',num2str(tStop)) % even numerical parameters must be sent as strings

It is a little more complicated using parsim. You have to first create simulink simulation object and then set its parameters. Something like this. I show it just for one model but you could do it in a loop for multiple model runs.

% make a simulink simulation input object
in =  Simulink.SimulationInput('myModel')

% set the stop time parameter
tStop = 45; % you could have more code to determine stop time
in = in.setModelParameter('StopTime',num2str(45))

% run the simulation
simout = parsim(in)

[Florian Rössing]

Thank you, but I know that. My problem is completly different however. I use parsim to simulate many inputs in parallel with every input having a different length that is not known by the program.

I would have to load every input i want to simulate, extract the length of the timeseries in it and than hand that information to parsim somehow. I am asking if there is a setting where simulink looks at its external input to know how long a simulation should be.

[Jon]

Sorry, I was editing my answer while you were commenting so we crossed each other. As you can see in my edit, I did realize that you were using parsim, but you still would have to find the final time in each time series and set that explicitly as the stop time. I would think you could set up a loop to do that.

I looked a little further, but I also didn't see a setting so that Simulink would stop at the last point in an input time series. Funny, you would think that would be a natural thing to do. They allow you to extrapolate, set to zero, hold constant, but not just stop

[Florian Rössing]

Exactly what i was thinking. It is the most trivial thought here.

Now my program is a lot slower, but I will have to stick with that:/

Not the answer I was hoping for, but the correct one.

Thank you.