# OESymmetryNumber¶

unsigned OESymmetryNumber(const OEMolBase &mol, bool useH=true,
double threshold=0.05)
bool OESymmetryNumber(const OEMCMolBase &mol, unsigned *symCtArray,
bool useH=true, double threshold=0.05)


Calculates the symmetry number of the molecule. For the overload with OEMolBase as imput molecule, the symmetry number is the return value. For the OEMCMolBase overload, the symmetry numbers are returned in the symCtdArray array. The symCtArray passed to this function should be of length fit.GetMaxConfIdx(). The useH flag indicates whether symmetry calculation should use the hydrogen atoms of the molecule or ignore them. Root mean squared deviation between conformations are performed internally and accepted as identical based on the specified threshold. For the OEMCMolBase overload the return value is True if calculation completes successfully, and False otherwise.

mol
The molecule to calculate symmetry number.
useH
Flag indicating if hydrigen atoms should be considered explicitly.
threshold
Thershold for root mean squared deviation (RMSD) comparison.
symCtArray
Array containing calculated symmetry numbers in a multi-conformer input molecule.