When simulating the model I build in dymola, it started with some error about initialization but ended with a success. Does this mean the nonlinear solver handled the error successfully or not?
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During the initialization the solver is searching for a consistent set of variables using e.g. Newton's method. While doing this it can happen, that variables get out of their valid range. In your case, this means that the square root of a negative number shall be computed. The solver recognizes this problem, skips the computation of this point and prints the message you see. Afterwards it tries to continue with other values (in the "attempt to handle this problem"). In your case the algorithm succeeds in doing so, which is why your simulation is started and finished successfully.
If you want to avoid such messages, it can help to set suitable start values for the variables used in the iteration. As a more advanced option you could try to use the homotopy operator described here. Other possibilities are listed here.
Markus A.
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