MATLAB: How to automatically change the dataset logging filename each time I run the simulation

changefilenameinitfcnloggingsimulink

I would like to log signals from my Simulink model to a file for later analysis. I am trying to incorporate a timestamp into the filename so that each successive simulation run does not overwrite a previous results file. I have the checkbox next to 'Log Dataset data to file' in the configuration parameters selected and the model will successfully log to the static filename I specify in that dialog.

In order to dynamically update the output filename each time I run the model, I have tried calling 'set_param' from the InitFcn callback but get the following error:

Changing property 'LoggingFileName' is not allowed.

How can I achieve the goal of automatically changing the dataset logging filename each time I run the simulation?

Best Answer

When InitFcn is called, the 'LoggingFileName' value is already set and is thus considered a read-only parameter.

The desired behavior can be accomplished using a wrapper MATLAB script. For example:

for i = ...
    set_param(...);
    sim(model_name); % Programmatically simulate the model
end

Related Solutions

MATLAB: How to set default signal logging properties in Simulink Data Inspector

Some signal logging properties can be set to a default value from the Simulink model canvas. This is done by right-clicking the signal logging icon shown above the logged signal line (resembling the WiFi symbol), and selecting "Properties". Any properties set in this dialog box will apply to all simulation runs.

For properties that cannot be set to a default value from the model canvas, you can change the setting programmatically at the end of each simulation. The code below demonstrates how this can be done. It changes the setting of all logged signals from the latest simulation run to use "zoh" as the "Interp Method". You can place this code in the model's "StopFcn", so that it automatically executes at the end of every simulation. To edit the "StopFcn" callback, go to File > Model Properties > Model Properties > Callbacks.

% Get run IDs for most recent run
allIDs = Simulink.sdi.getAllRunIDs;
runID = allIDs(end);
% Get Run object
run = Simulink.sdi.getRun(runID);
% Change property for all signals in the latest run
for i = 1:run.SignalCount
    % Get signal IDs
    sigID = run.getSignalIDByIndex(i);
    if (run.isValidSignalID(sigID))
        % Get signal
        sig = Simulink.sdi.getSignal(sigID);
        % Change signal interpolation method
        sig.InterpMethod = 'zoh';
    end
end

To learn more about using Simulink Data Inspector programmatically, you may refer to the following documentation page:

https://www.mathworks.com/help/simulink/ug/record-and-inspect-signal-data-programmatically.html

MATLAB: How to modify the model callback functions programmatically

You may use the "set_param" function.

Here is the example code about how to change the 'InitFcn' programmatically using one of our shipped example 'vdp.slx':

>> vdp
>> set_param('vdp','InitFcn','a = 2;')

>> vdp
>> set_param(gcs,'InitFcn','a = 2;')

Please reference our documentation page for more details about the 'set_param' function and Model Callbacks:

https://www.mathworks.com/help/simulink/slref/set_param.html

https://www.mathworks.com/help/simulink/ug/model-callbacks.html#btoznm0

Best Answer

Related Solutions

MATLAB: How to set default signal logging properties in Simulink Data Inspector

MATLAB: How to modify the model callback functions programmatically

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