unsigned int OEDetermineRingSystems(const OEMolBase &mol, unsigned int *rings)
OEDetermineRingSystems(const OEMolBase mol) -> number_of_rings, ring_idx_per_atom
Determines the ring systems of a molecule. The return
value is the number of ring systems found in the molecule. If
the molecule is acyclic, the return value is zero. The ‘rings’ array
must contain at least
elements, and upon return it contains a mapping indexed by
OEAtomBase.GetIdx of which ring system each atom is
in. The ring systems are numbered from one, up to an including the
return value of the function. Atoms that aren’t contained in a ring,
i.e. for which
false, are mapped to the value zero.
In Python, OEDetermineRingSystems returns a two item tuple. The first item in the tuple is the number of independent ring systems found. The second item in the tuple is a list of the atom ring membership as described as the ‘rings’ parameter above.
Ring Systems Identification section