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modelicadymola

decrease the mat file size of Dymola result

The result of Dymola simulation is .mat file, which might be very big. Here is a series of results of a Power plant model, the simulation time interval is 0-100000s, but I only need the data during 90000 to 100000s, so is there any way to let Dymola only output the data of 90000 to 100000s?

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Solution

  • There is a section called "Variable frequency of output points" in the Dymola User manual. There you'll find an explanation on how Advanced.Simulation.VariableInterval=true and statements like

    when time >=… then
  Dymola.Simulation.SetOutputInterval(…);
end when;

    will enable you to set the output interval depending on the simulation time.

    The example shown there is:

    model VariableOutputInterval "demonstrate the use of variable output interval in a model"
  Real x;
equation
  x = sin(10*time);
  
  when initial() then
    Dymola.Simulation.SetOutputInterval(0.1);
  end when;

  when time >= 0.5 then
    Dymola.Simulation.SetOutputInterval(0.05);
  end when;

  when time >= 1.1 then
    Dymola.Simulation.SetOutputInterval(0.002);
  end when;
end VariableOutputInterval;

    Also there are two notes:

    • The only way to “reset” the interval length to the one in the simulation setup is to explicitly set that interval, this is done in the last when statement above.
    • You must have a separate when statement for each time.