Q:

Find the function usage in the model I build in dymola

In dymola, when I simulated a model, I got an error showing that the parameter for some function is wrong, and the log showed the function calling stack, so I changed to the "used classes" view to show all the code used, but I didn't find any usage of the function showed in the error message. 
My question is that how should I find the usage of this function in my model?

A:

For tph1 it is likely that the problem is that it is called indirectly, and called functions are as default not included in the "Used Classes", but that can be changed in the context menu of used classes (i.e. right-click):

(Note that the names in the dialog vary slightly depending on Dymola version.)
The function with a name ending in _der is likely an automatically generated derivative-function - based on the name before _der. (Using automatic/algorithmic differentiation.)
But using dsmodel.mof is also a possibility.

