chemcoord.Zmat.subs

Zmat.subs(*args, **kwargs)

Substitute a symbolic expression in ['bond', 'angle', 'dihedral']

This is a wrapper around the substitution mechanism of sympy. Any symbolic expression in the columns ['bond', 'angle', 'dihedral'] of self will be substituted with value.

Note

This function is not side-effect free. If all symbolic expressions are evaluated and are concrete numbers and perform_checks is True, a check for the transformation to cartesian coordinates is performed. If no InvalidReference exceptions are raised, the resulting cartesian is written to self._metadata['last_valid_cartesian'].

Parameters:
  • symb_expr (sympy expression) –
  • value –
  • perform_checks (bool) – If perform_checks is True, it is asserted, that the resulting Zmatrix can be converted to cartesian coordinates. Dummy atoms will be inserted automatically if necessary.
Returns:

Zmatrix with substituted symbolic expressions. If all resulting sympy expressions in a column are numbers, the column is recasted to 64bit float.
Return type:

Zmat