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ell::SC_PartitionFunction Class Reference

#include <StateCollector.hh>

Inheritance diagram for ell::SC_PartitionFunction:

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Detailed Description

This StateCollector implementation counts the number of collected States and calculates the canonical partition function Z of these States. Z = sum( e^(-E(State)/kT) ) is the sum of the Boltzmann weights of all States. The kT value is derived from LandscapeTopology::BOLTZMANN_KT.

NOTE : if the energy of collected states is << 0 one will face immense rounding errors due to the summing of e^(-energy). In this case we recommend the SC_PartitionFunction_Shifted state collector which uses a more advanced handling of the Boltzmann weights based on energy differences instead of pure energies (without negative impact in accuracy).

Definition at line 369 of file StateCollector.hh.

Public Member Functions

virtual void add (const State &s)
double getEnergy (void) const
virtual const State *const getLastAdded () const
double getZ (void) const
 SC_PartitionFunction ()
virtual size_t size () const
virtual ~SC_PartitionFunction ()

Protected Attributes

StatelastAdded
size_t stateCount
double Z


Constructor & Destructor Documentation

ell::SC_PartitionFunction::SC_PartitionFunction (  ) 

Construction.

Definition at line 8 of file SC_PartitionFunction.cc.

ell::SC_PartitionFunction::~SC_PartitionFunction (  )  [virtual]

Destruction.

Definition at line 13 of file SC_PartitionFunction.cc.


Member Function Documentation

void ell::SC_PartitionFunction::add ( const State s  )  [virtual]

This function makes the collector manage the given State.

Parameters:
s the added State

Reimplemented from ell::SC_Counting.

Definition at line 20 of file SC_PartitionFunction.cc.

double ell::SC_PartitionFunction::getEnergy ( void   )  const

Calculates the free energy of the collected State ensemble based on the canonical partition function : E = -kT * ln(Z)

Returns:
the energy of the State ensemble

Definition at line 38 of file SC_PartitionFunction.cc.

const State *const ell::SC_Counting::getLastAdded (  )  const [virtual, inherited]

Returns last added State.

Returns:
last added State

Implements ell::StateCollector.

Definition at line 37 of file SC_Counting.cc.

double ell::SC_PartitionFunction::getZ ( void   )  const

Access to the canonical partition function of the collected States.

Returns:
the partition function Z

Definition at line 31 of file SC_PartitionFunction.cc.

size_t ell::SC_Counting::size (  )  const [virtual, inherited]

Returns number of added States.

Returns:
the number of added states

Implements ell::StateCollector.

Definition at line 30 of file SC_Counting.cc.


Field Documentation

State* ell::SC_Counting::lastAdded [protected, inherited]

the last added State

Definition at line 57 of file StateCollector.hh.

size_t ell::SC_Counting::stateCount [protected, inherited]

the number of added States

Definition at line 59 of file StateCollector.hh.

double ell::SC_PartitionFunction::Z [protected]

the current canonical partition function of the collected States

Definition at line 384 of file StateCollector.hh.


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