BUG: data handler fails if no chem variable is used
MLAir was started without any chemical as input (but still as target).
First guess on error origin
Data handler cannot handle, if no chemical is included in input space when checking for negative concentrations.
Problem is line 409 in
if statement to check, if the
used_chem_vars variable has a length of 1 or longer. Only apply clipping in this case.