Why has an FMU exported as FMI1 different statistics than if exported as FMI2

Question

Let's say I export a model in Dymola with FMI-1 standard:

translateModelFMU("SomeModel", false, "", "1", "me", false)

and then I export the same model with FMI-2 standard:

translateModelFMU("SomeModel", false, "", "2", "me", false)

I noticed that the model statistics (Sizes of nonlinear systems of equations, Initialization problem) changes.

Can anybody explain why?

Answer 1

The FMI standard version 2.0 has a number of additions to the FMI standard that can allow a tool to more efficiently simulate the exported model. These changes include:

• Support for Jacobian matrices

• New classification of interface variables

• Continuous state variables are explicitly listed as FMU variables

More information about the changes can be found in this paper from the Modelica'2012 conference: Functional Mockup Interface 2.0: The Standard for Tool independent Exchange of Simulation Models