Provide more informative error messages for problems in model-simplification
The attached file has a variable defined as 0, which causes the preprocessor to replace it by 0. But this results in a cryptic error message
ERROR: Division by zero!
terminate called after throwing an instance of 'DataTree::DivisionByZeroException'
There is no clue for a user how to fix it. GT.mod
Similarly
returns
Error: In not used in the model block
because the variable is always multiplied by 0.