Note

The aromaticity (see Aromaticity Perception chapter) has to be perceived by calling the OEAssignAromaticFlags function prior to calling OEPerceiveCIPStereo.

OEPerceiveCIPStereo

unsigned int OEPerceiveCIPStereo(const OEMolBase& mol, const OEAtomBase* atom);

Perceives the Cahn-Ingold-Prelog descriptor for the given atom. The return value is taken from the OECIPAtomStereo namespace.

For a chiral atom center the function returns

• either OECIPAtomStereo.R or OECIPAtomStereo.S, if the atom has specified stereochemistry
• OECIPAtomStereo.UnspecStereo if the CIP atom stereo center has no specified stereo (i.e. when OEAtomBase.HasStereoSpecified returns false),

The function always returns OECIPAtomStereo.NotStereo for the following atoms:

• non-chiral atoms
• atoms that have invalid valence (checked by OECheckAtomValence)

See also

• OESetCIPStereo to set atom stereo from CIP stereo descriptor
• CIP Stereo Perception section

unsigned int OEPerceiveCIPStereo(const OEMolBase& mol, const OEBondBase* bond);

Perceives the Cahn-Ingold-Prelog descriptor for the given bond stereo center. The return value is taken from the OECIPBondStereo namespace.

For a double bond, the function returns

• either OECIPBondStereo.E or OECIPBondStereo.Z, if the bond has specified stereochemistry
• OECIPBondStereo.UnspecStereo if the CIP bond stereo center has no specified stereo (i.e. when OEBondBase.HasStereoSpecified returns false)

For a non-chiral bond, the function always returns OECIPBondStereo.NotStereo.

See also

• OESetCIPStereo to set bond stereo from CIP stereo descriptor
• CIP Stereo Perception section