Descriptors notation

The name of descriptors consists of several sections separated by vertical bar symbol.

#		Reaction labela (optional)	Descriptor typeb	Descriptor valuec	(reserved)	(reserved)	Number of atoms	(reserved)	(reserved)	Atom labelingd	SMILES
	Possible values	p/r/pr	S/M	n/p			integer			elm/none/...	SMILES
	Examples
1	`	S	n			6			none	A-A(-A)-A.A=A`
2	`	M	n			5			elm	C.C(-C=O)-H`
3	`pr	M	p			4			elm	C-C-C.O`	pr

^a p or r is product or reactant mixture descriptor, pr is a difference between products and reactants mixture descriptors.
^b S means a single compound descriptor, M - a mixture descriptor.
^a n means the count of fragments (weighted by compound amount in case of mixture descriptors), p means probability of fragment occurring (calculated as a ratio of a descriptor value to sum of all descriptors. Note: single and mixture descriptors processed separately).
^d elm means atoms labeled by element, none - no labels to encode just topology of molecules, other values are allowed based on used defined atom properties in the input sdf-file.

Examples description:

1. Descriptor denotes the number of six atom fragments in a single compound (or a component of a mixture) disregarding atom labels (topology fragment descriptor).
2. Descriptor denotes the number of concurrence of fragments C and C(C=O)H belonging to two different components in a mixture.
3. Descriptor denotes the difference between product and reactant relative occurrence frequency of two fragments CCC and O belonging to two different reactants and two different products (mixtures of reactants and products considered separately).