CDPL::Chem::HashCodeCalculator Class Reference

Computes 64-bit hash codes that are characteristic for the topology of a molecular graph and the properties of its atoms and bonds. More...

#include <HashCodeCalculator.hpp>

Classes
class	DefAtomHashSeedFunctor
	Default functor for the generation of atom hash seeds. More...
class	DefBondHashSeedFunctor
	Default functor for the generation of bond hash seeds. More...

Public Types
typedef std::function< std::uint64_t(const Atom &)>	AtomHashSeedFunction
	Type of the generic functor class used to store user-defined functions or function objects for the generation of initial atom hash codes. More...
typedef std::function< std::uint64_t(const Bond &)>	BondHashSeedFunction
	Type of the generic functor class used to store user-defined functions or function objects for the generation of initial bond hash codes. More...

Public Member Functions
	HashCodeCalculator ()
	Constructs the HashCodeCalculator instance. More...
	HashCodeCalculator (const MolecularGraph &molgraph)
	Constructs the HashCodeCalculator instance and calculates the hash code of the molecular graph molgraph. More...
	HashCodeCalculator (const HashCodeCalculator &)=delete
HashCodeCalculator &	operator= (const HashCodeCalculator &)=delete
void	setAtomHashSeedFunction (const AtomHashSeedFunction &func)
	Allows to specify a custom function for the generation of initial atom hash codes. More...
void	setBondHashSeedFunction (const BondHashSeedFunction &func)
	Allows to specify a custom function for the generation of initial bond hash codes. More...
std::uint64_t	calculate (const MolecularGraph &molgraph)
	Calculates the hash code of the molecular graph molgraph. More...
std::uint64_t	getResult () const
	Returns the result of the last hash code calculation. More...

Static Public Attributes
static constexpr unsigned int	DEF_ATOM_PROPERTY_FLAGS
	Specifies the default set of atomic properties considered in the generation of initial atom hash codes by HashCodeCalculator::DefAtomHashSeedFunction. More...
static constexpr unsigned int	DEF_BOND_PROPERTY_FLAGS
	Specifies the default set of bond properties considered in the generation of initial bond hash codes by HashCodeCalculator::DefBondHashSeedFunction. More...

Detailed Description

Computes 64-bit hash codes that are characteristic for the topology of a molecular graph and the properties of its atoms and bonds.

The algorithm assigns initial seeds to each atom and bond through the user-replaceable functors HashCodeCalculator::AtomHashSeedFunction and HashCodeCalculator::BondHashSeedFunction, iteratively propagates the seeds over the graph topology in the spirit of Morgan-style extended connectivity hashing, and finally folds the per-atom hash codes into a single 64-bit unsigned integer result via an SHA-style mixing step. The default seed functors (DefAtomHashSeedFunctor, DefBondHashSeedFunctor) take into account the property flags specified by the static constants DEF_ATOM_PROPERTY_FLAGS and DEF_BOND_PROPERTY_FLAGS, respectively.

See also

[MHASH]

Member Typedef Documentation

AtomHashSeedFunction

typedef std::function<std::uint64_t(const Atom&)> CDPL::Chem::HashCodeCalculator::AtomHashSeedFunction

Type of the generic functor class used to store user-defined functions or function objects for the generation of initial atom hash codes.

Functions or function objects for the generation of atom hash seeds are required to take the atom (as a const reference to Chem::Atom) as argument and return the hash seed as an integer of type std::uint64_t (see [FUNWRP]).

BondHashSeedFunction

typedef std::function<std::uint64_t(const Bond&)> CDPL::Chem::HashCodeCalculator::BondHashSeedFunction

Type of the generic functor class used to store user-defined functions or function objects for the generation of initial bond hash codes.

Functions or function objects for the generation of bond hash seeds are required to take the bond (as a const reference to Chem::Bond) as argument and return the hash seed as an integer of type std::uint64_t (see [FUNWRP]).

Constructor & Destructor Documentation

HashCodeCalculator() [1/3]

CDPL::Chem::HashCodeCalculator::HashCodeCalculator

(

)

Constructs the HashCodeCalculator instance.

HashCodeCalculator() [2/3]

CDPL::Chem::HashCodeCalculator::HashCodeCalculator

(

const MolecularGraph &

molgraph

)

Constructs the HashCodeCalculator instance and calculates the hash code of the molecular graph molgraph.

The calculated hash code can be retrieved by a call to getResult().

Parameters

molgraph

The molecular graph for which the hash code has to be calculated.

HashCodeCalculator() [3/3]

CDPL::Chem::HashCodeCalculator::HashCodeCalculator ( const HashCodeCalculator &  )

delete

Member Function Documentation

operator=()

HashCodeCalculator& CDPL::Chem::HashCodeCalculator::operator= ( const HashCodeCalculator &  )

delete

setAtomHashSeedFunction()

void CDPL::Chem::HashCodeCalculator::setAtomHashSeedFunction

(

const AtomHashSeedFunction &

func

)

Allows to specify a custom function for the generation of initial atom hash codes.

Parameters

func	A HashCodeCalculator::AtomHashSeedFunction instance that wraps the target function.

Note

By default, atom hash seeds are generated by HashCodeCalculator::DefAtomHashSeedFunctor.

setBondHashSeedFunction()

void CDPL::Chem::HashCodeCalculator::setBondHashSeedFunction

(

const BondHashSeedFunction &

func

)

Allows to specify a custom function for the generation of initial bond hash codes.

Parameters

func	A HashCodeCalculator::BondHashSeedFunction instance that wraps the target function.

Note

By default, bond hash seeds are generated by HashCodeCalculator::DefBondHashSeedFunctor.

calculate()

std::uint64_t CDPL::Chem::HashCodeCalculator::calculate

(

const MolecularGraph &

molgraph

)

Calculates the hash code of the molecular graph molgraph.

Parameters

molgraph

The molecular graph for which to calculate the hash code.

Returns

The hash code of the molecular graph molgraph.

getResult()

std::uint64_t CDPL::Chem::HashCodeCalculator::getResult

(

)

const

Returns the result of the last hash code calculation.

Returns

The result of the last hash code calculation, or zero if a calculation has not yet been performed.

Member Data Documentation

DEF_ATOM_PROPERTY_FLAGS

constexpr unsigned int CDPL::Chem::HashCodeCalculator::DEF_ATOM_PROPERTY_FLAGS

staticconstexpr

Initial value:

=
                AtomPropertyFlag::TYPE | AtomPropertyFlag::ISOTOPE |
                AtomPropertyFlag::H_COUNT | AtomPropertyFlag::FORMAL_CHARGE |
                AtomPropertyFlag::CIP_CONFIGURATION | AtomPropertyFlag::AROMATICITY

Specifies the default set of atomic properties considered in the generation of initial atom hash codes by HashCodeCalculator::DefAtomHashSeedFunction.

DEF_BOND_PROPERTY_FLAGS

constexpr unsigned int CDPL::Chem::HashCodeCalculator::DEF_BOND_PROPERTY_FLAGS

staticconstexpr

Initial value:

=
                BondPropertyFlag::ORDER | BondPropertyFlag::TOPOLOGY |
                BondPropertyFlag::AROMATICITY | BondPropertyFlag::CIP_CONFIGURATION

Specifies the default set of bond properties considered in the generation of initial bond hash codes by HashCodeCalculator::DefBondHashSeedFunction.

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The documentation for this class was generated from the following file:

• HashCodeCalculator.hpp