OESameChain

bool OESameChain(const OEAtomBase &atom1, const OEResidue &atom2)
bool OESameChain(const OEResidue &res1, const OEResidue &res2)

Determines whether two atoms or their respective OEResidue s are in the same chain. This returns true if both residues have the same NMR model number, OEResidue.GetModelNumber, and the same chain identifier, OEResidue.GetChainID.