exception chemcoord.exceptions.InvalidReference(message=None, i=None, b=None, a=None, d=None, already_built_cartesian=None, zmat_after_assignment=None)[source]

Raised when the i-th atom uses an invalid reference.

May carry several attributes:

  • i: Index of the atom with an invalid refernce.
  • b, a, and d: Indices of reference atoms.
  • already_built_cartesian: The cartesian of all atoms up to (i-1)
  • zmat_after_assignment: Attached information if it was raised from the safe assignment methods (Zmat.safe_loc() and Zmat.unsafe_loc()).