I need to use DAE formulation of models, and wonder about the initialization… From the documentation:
Question: Does this imply that those
differential_vars which are differential, are assumed to have correct initial values, and that only the non-differential variables will be adjusted in the initialization phase? In other words, that those marked as differential variables will keep their initial values after the initialization phase, and that the non-differential variables may be adjusted?
The reason why I ask is that I need to know whether I can specify initial states, and know that these are not changed.
There is an added problem to this, of course: for DAEs, the state is not necessarily the same as the differential variable. The state is the vector of freely selectable variables which specifies the solution, and this is not necessarily the same as the differential variables in a model… If the model has more differential variables than the number of states, or fewer differential variables than the number of states, how do I handle that case?