This class wraps a MultiFunction and stores computed values using a hashtable to avoid reevaluating a function at points where it already has been evaluated. More...

#include <FunctionLookupTable.hpp>

Public Member Functions
void	addEntry (base::DataVector const &x, double y)
	Adds a function value into the storage. More...

bool	containsEntry (base::DataVector const &x)

void	deserialize (std::string const &value)
	Retrieves stored values from a string generated by serialize(). More...

double	eval (base::DataVector const &x)
	Does the same as operator() (can be called from Python, for example). More...

double	evalThreadsafe (base::DataVector const &x)
	Does the same as eval(), but uses a mutex whenever the hashtable is accessed. More...

	FunctionLookupTable (MultiFunction const &func)

size_t	getNumEntries () const

double	operator() (base::DataVector const &x)
	Evaluates the function at the point x. More...

std::string	serialize ()
	Stores the stored values into a string. More...

MultiFunction	toMultiFunction () const
	This is a convenience function that is especially nice for python code. More...

Detailed Description

This class wraps a MultiFunction and stores computed values using a hashtable to avoid reevaluating a function at points where it already has been evaluated.

This means that only the exact same parameter will allow retrieving the function value.

Constructor & Destructor Documentation

◆ FunctionLookupTable()

sgpp::combigrid::FunctionLookupTable::FunctionLookupTable ( MultiFunction const & func )

explicit

Member Function Documentation

◆ addEntry()

void sgpp::combigrid::FunctionLookupTable::addEntry	(	base::DataVector const &	x,
		double	y
	)

Adds a function value into the storage.

Parameters

x	Parameter of the function.
y	Result of the function evaluation.

Referenced by deserialize(), evalThreadsafe(), and operator()().

◆ containsEntry()

bool sgpp::combigrid::FunctionLookupTable::containsEntry ( base::DataVector const & x )

Returns: true iff the hashtable contains a function value for the parameter x.

◆ deserialize()

void sgpp::combigrid::FunctionLookupTable::deserialize ( std::string const & value )

Retrieves stored values from a string generated by serialize().

References addEntry(), sgpp::combigrid::FloatSerializationStrategy< T >::deserialize(), python.statsfileInfo::i, python.utils.statsfile2gnuplot::j, sgpp::combigrid::DefaultSerializationStrategy< T >::serialize(), serialize(), and sgpp::combigrid::split().

Referenced by python.learner.formatter.LearnedKnowledgeFormatter.LearnedKnowledgeFormatter::deserializeFromFile(), python.learner.formatter.GridFormatter.GridFormatter::deserializeFromFile(), python.utils.GzipSerializer.GzipSerializer::deserializeFromFile(), python.uq.analysis.asgc.ASGCKnowledgeFormatter.ASGCKnowledgeFormatter::deserializeFromFile(), python.uq.sampler.asgc.ASGCSamplerFormatter.ASGCSamplerFormatter::deserializeFromFile(), and python.uq.uq_setting.UQSettingFormatter.UQSettingFormatter::deserializeFromFile().

◆ eval()

double sgpp::combigrid::FunctionLookupTable::eval ( base::DataVector const & x )

Does the same as operator() (can be called from Python, for example).

Referenced by python.uq.analysis.asgc.ASGCAnalysis.ASGCAnalysis::estimateDensity().

◆ evalThreadsafe()

double sgpp::combigrid::FunctionLookupTable::evalThreadsafe ( base::DataVector const & x )

Does the same as eval(), but uses a mutex whenever the hashtable is accessed.

Crucially, the mutex is not locked when evaluating the function, such that multiple function evaluations can be done in parallel.

References addEntry().

◆ getNumEntries()

size_t sgpp::combigrid::FunctionLookupTable::getNumEntries ( ) const

Returns: the number of stored function values.

◆ operator()()

double sgpp::combigrid::FunctionLookupTable::operator() ( base::DataVector const & x )

Evaluates the function at the point x.

If the function has already been evaluated at this point, the stored result will be used.

References addEntry().

◆ serialize()

std::string sgpp::combigrid::FunctionLookupTable::serialize ( )

Stores the stored values into a string.

References python.statsfileInfo::i, sgpp::combigrid::join(), and sgpp::combigrid::FloatSerializationStrategy< T >::serialize().

Referenced by deserialize(), python.utils.GzipSerializer.GzipSerializer::serializeToFile(), python.learner.formatter.LearnerFormatter.LearnerFormatter::serializeToFile(), python.learner.formatter.LearnedKnowledgeFormatter.LearnedKnowledgeFormatter::serializeToFile(), python.learner.formatter.GridFormatter.GridFormatter::serializeToFile(), python.uq.analysis.asgc.ASGCKnowledgeFormatter.ASGCKnowledgeFormatter::serializeToFile(), python.uq.sampler.asgc.ASGCSamplerFormatter.ASGCSamplerFormatter::serializeToFile(), and python.uq.uq_setting.UQSettingFormatter.UQSettingFormatter::serializeToFile().

◆ toMultiFunction()

MultiFunction sgpp::combigrid::FunctionLookupTable::toMultiFunction ( ) const

This is a convenience function that is especially nice for python code.

Returns: a MultiFunction object that delegates each call to this FunctionLookupTable.

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

combigrid/src/sgpp/combigrid/storage/FunctionLookupTable.hpp
combigrid/src/sgpp/combigrid/storage/FunctionLookupTable.cpp

Public Member Functions