Aleph::CA::Entropy_Observer< MaxState > Class Template Reference

Records the Shannon entropy of the state distribution. More...

#include <ca-observer.H>

Collaboration diagram for Aleph::CA::Entropy_Observer< MaxState >:

Public Member Functions
	Entropy_Observer ()=default
	Construct an empty entropy observer.
const Array< double > &	entropy () const noexcept
	Return the entropy time series.
std::size_t	size () const noexcept
	Return the number of entropy samples.
void	reset () noexcept
	Clear all entropy samples.
template<typename Lattice >
void	on_step_begin (const std::size_t step, const Lattice &frame)
	Record entropy of the initial frame.
template<typename Lattice >
void	on_step_end (const std::size_t step, const Lattice &frame)
	Record entropy after a completed step.

Private Attributes
Array< double >	entropy_
bool	seeded_ = false

Detailed Description

template<std::size_t MaxState>
class Aleph::CA::Entropy_Observer< MaxState >

Records the Shannon entropy of the state distribution.

Computes the entropy in nats over the integer states in [0, MaxState). Pushes one sample per step (including the initial frame).

Template Parameters

MaxState

exclusive upper bound on the state values.

Complexity

Callbacks are O(N + MaxState) per sampled frame.

Thread-safety

Thread-safe for concurrent readers after simulation stops; not thread-safe for concurrent callbacks.

Exception-safety

Strong guarantee unless array allocation throws.

Definition at line 548 of file ca-observer.H.

Constructor & Destructor Documentation

Entropy_Observer()

template<std::size_t MaxState>

Aleph::CA::Entropy_Observer< MaxState >::Entropy_Observer ( )

default

Construct an empty entropy observer.

Exceptions

This	function does not throw.

Member Function Documentation

entropy()

template<std::size_t MaxState>

const Array< double > & Aleph::CA::Entropy_Observer< MaxState >::entropy ( ) const

inlinenoexcept

Return the entropy time series.

Returns

entropies in nats, including the initial frame.

Exceptions

This	function does not throw.

Definition at line 563 of file ca-observer.H.

References Aleph::CA::Entropy_Observer< MaxState >::entropy_.

on_step_begin()

template<std::size_t MaxState>

template<typename Lattice >

void Aleph::CA::Entropy_Observer< MaxState >::on_step_begin ( const std::size_t  step, const Lattice &  frame  )

inline

Record entropy of the initial frame.

Template Parameters

Lattice

lattice type.

Parameters

[in]	step	step index about to run.
[in]	frame	frame before the step.

Exceptions

std::bad_alloc

if appending the sample allocates.

Definition at line 596 of file ca-observer.H.

References Aleph::and, Aleph::Array< T >::append(), Aleph::blossom_maximum_cardinality_matching(), Aleph::CA::Entropy_Observer< MaxState >::entropy_, Aleph::CA::Entropy_Observer< MaxState >::seeded_, and Aleph::CA::shannon_entropy().

on_step_end()

template<std::size_t MaxState>

template<typename Lattice >

void Aleph::CA::Entropy_Observer< MaxState >::on_step_end ( const std::size_t  step, const Lattice &  frame  )

inline

Record entropy after a completed step.

Template Parameters

Lattice

lattice type.

Parameters

[in]	step	completed step index, ignored.
[in]	frame	frame after the step.

Exceptions

std::bad_alloc

if appending the sample allocates.

Definition at line 612 of file ca-observer.H.

References Aleph::Array< T >::append(), Aleph::blossom_maximum_cardinality_matching(), Aleph::CA::Entropy_Observer< MaxState >::entropy_, and Aleph::CA::shannon_entropy().

reset()

template<std::size_t MaxState>

void Aleph::CA::Entropy_Observer< MaxState >::reset ( )

inlinenoexcept

Clear all entropy samples.

Exceptions

This	function does not throw.

Complexity

O(size()).

Definition at line 583 of file ca-observer.H.

References Aleph::Array< T >::clear(), Aleph::CA::Entropy_Observer< MaxState >::entropy_, and Aleph::CA::Entropy_Observer< MaxState >::seeded_.

size()

template<std::size_t MaxState>

std::size_t Aleph::CA::Entropy_Observer< MaxState >::size ( ) const

inlinenoexcept

Return the number of entropy samples.

Returns

sample count.

Exceptions

This	function does not throw.

Definition at line 572 of file ca-observer.H.

References Aleph::CA::Entropy_Observer< MaxState >::entropy_, and Aleph::Array< T >::size().

Member Data Documentation

entropy_

template<std::size_t MaxState>

Array<double> Aleph::CA::Entropy_Observer< MaxState >::entropy_

private

Definition at line 550 of file ca-observer.H.

Referenced by Aleph::CA::Entropy_Observer< MaxState >::entropy(), Aleph::CA::Entropy_Observer< MaxState >::on_step_begin(), Aleph::CA::Entropy_Observer< MaxState >::on_step_end(), Aleph::CA::Entropy_Observer< MaxState >::reset(), and Aleph::CA::Entropy_Observer< MaxState >::size().

seeded_

template<std::size_t MaxState>

bool Aleph::CA::Entropy_Observer< MaxState >::seeded_ = false

private

Definition at line 551 of file ca-observer.H.

Referenced by Aleph::CA::Entropy_Observer< MaxState >::on_step_begin(), and Aleph::CA::Entropy_Observer< MaxState >::reset().

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

• ca-observer.H