extracting timestep data via. callback functions.

[Marina Kovaleva]

Hello,

I am having some trouble with callback functions for capturing info at each timestep for 1D simulations. The simulation runs successfully, but the timestep and steady-state callback functions are only activated once for the simulation, but the stats show multiple timesteps. I am wondering how to get datasets for many timesteps.

Code files attached:
- mech (UCSD)

- code file + run file -code is run from an instance of TimeStepCantera()

[Marina Kovaleva]

Just to clarify my question - the callback function only activates once during the simulation. I would like to know how to activate it for every time the timestep advances? Thank you in advance for your help and support.

Marina

[Ray Speth]

Hi Marina,

You need to pass the callback function itself to the set_time_step_callback method. What you’re doing is calling the callback at a specific time, then passing the result of that (the None object) to set_time_step_callback, which is the way to specify that there is no callback function. Also, because of the way that it’s implemented, the callback function needs to return a number; this value is arbitrary, since it is not actually used.

For example, you want to write something like:

def timestep_callback(_): print("timstep callback") return 0.0

and then later for the setup:

self.f.set_time_step_callback(timestep_callback)

Hope this helps.

Regards,
Ray

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