Class to represent the Bin Packing Problem. More...

#include <BPP.h>

Inheritance diagram for BPP:

Public Member Functions
	BPP ()
	Construct a new BPP::BPP object.

	BPP (const string &pathToInstance)
	Construct a new BPP::BPP object from the data in the file in the path. More...

	BPP (const int &numberOfVars, const int &capacity, const vector< int > &items)

	BPP (const BPP *)
	Construct a new BPP::BPP object from another BPP object. More...

float	getUpperLimit (int i) const override
	Returns the upper limit of the variable i In this case, the upper limit is the number of items - 1. More...

int	getOptimizationDirection (const int i) const override
	Gets the optimization direction of the problem. For the BPP is should always be Minimize. More...

float	getLowerLimit (int i) const override
	Returns the lower limit of the variable i In this case, the lower limit is 0. More...

string	getName () const override
	Returns the name of the problem. This method must be implemented in the subclasses. More...

void	evaluate (IntIntSolution &solution) const override
	Evaluates a bin assignment for the BPP instances represented in the object The fitness of the solution is the amount of unused space, as well as the number of bins for a specific solution. Falkenauer (1998) performance metric defined as: More...

bool	evaluateConstraints (IntIntSolution &ptr) const override
	Method to evaluate whether a solution is feasible or not. This method must be implemented in the subclasses. More...

IntIntSolution	createSolution () const override
	Creates a random solution for the BPP Each items is assigned to a random bin in the range [0, numberOfVars) More...

IntIntSolution	createSolution (ParallelPRNG &engine) const override
	Creates a random solution for the BPP Each items is assigned to a random bin in the range [0, numberOfVars) More...

int	getCapacity () const

void	setCapacity (int capacity)
	Updates the capacity of the instance. More...

const vector< int > &	getItems () const

void	readData (const string &path) override
	Reads the data from the file in the path. The file should contain a proper BPP instance with the following format: nItems Q w0 w1 ... wn-1. More...

json	to_json () const override

Public Member Functions inherited from Problem< IntIntSolution >
	Problem ()
	Creates a new Problem with all parameters to zero. More...

	Problem (const int &numberOfVars, const int &numberOfObjectives, const int &nCons)
	Construct a new Problem with all the given parameters. More...

	Problem (const Problem *copy)

virtual void	readData (const std::string &path)=0
	Method to read problem information from the given path. This method must be implemented in the subclasses. More...

int	getNumberOfVars () const
	Get the number of variables (dimension) of the problem. More...

void	setNumberOfVars (int nVars)
	Sets the number of variables (dimension) of the problem. More...

int	getNumberOfObjs () const
	Get the number of objectives of the problem. More...

void	setNumberOfObjs (int nObjs)
	Sets the number of objectives to the problem. More...

int	getNumberOfCons () const
	Get the number the constraint of the problem. More...

void	setNumberOfCons (int nCons)
	Sets the number of constraint of the problem. More...

Protected Attributes
vector< int >	items

int	capacity

std::string	pathToInstance

Protected Attributes inherited from Problem< IntIntSolution >
int	numberOfVars

int	numberOfObjs

int	numberOfCons

Detailed Description

Class to represent the Bin Packing Problem.

Constructor & Destructor Documentation

◆ BPP() [1/3]

BPP::BPP ( const string & path )

Construct a new BPP::BPP object from the data in the file in the path.

Parameters

path

◆ BPP() [2/3]

BPP::BPP	(	const int &	numberOfVars,
		const int &	capacity,
		const vector< int > &	items
	)

Generates a BPP problem with all the data given in the arguments

Parameters

numberOfVars
capacity
weights
profits

◆ BPP() [3/3]

BPP::BPP ( const BPP * bpp )

Construct a new BPP::BPP object from another BPP object.

Parameters

bpp

Member Function Documentation

◆ createSolution() [1/2]

IntIntSolution BPP::createSolution ( ) const

overridevirtual

Creates a random solution for the BPP Each items is assigned to a random bin in the range [0, numberOfVars)

Returns: IntIntSolution

Implements Problem< IntIntSolution >.

◆ createSolution() [2/2]

IntIntSolution BPP::createSolution ( ParallelPRNG & engine ) const

overridevirtual

Creates a random solution for the BPP Each items is assigned to a random bin in the range [0, numberOfVars)

Returns: IntIntSolution

Implements Problem< IntIntSolution >.

◆ evaluate()

void BPP::evaluate ( IntIntSolution & solution ) const

overridevirtual

Evaluates a bin assignment for the BPP instances represented in the object The fitness of the solution is the amount of unused space, as well as the number of bins for a specific solution. Falkenauer (1998) performance metric defined as:

(x) = \frac{\sum_{k=1}^{N} \left(\frac{fill_k}{C}\right)^2}{N}

Parameters

solution

Implements Problem< IntIntSolution >.

◆ evaluateConstraints()

bool BPP::evaluateConstraints ( IntIntSolution & sol ) const

inlineoverridevirtual

Method to evaluate whether a solution is feasible or not. This method must be implemented in the subclasses.

Parameters

sol	Solution (S) to evaluate

Returns: true if the solution is feasible; false otherwise

Implements Problem< IntIntSolution >.

◆ getLowerLimit()

float BPP::getLowerLimit ( int i ) const

overridevirtual

Returns the lower limit of the variable i In this case, the lower limit is 0.

Parameters

i

Returns: float

Implements Problem< IntIntSolution >.

◆ getName()

string BPP::getName ( ) const

inlineoverridevirtual

Returns the name of the problem. This method must be implemented in the subclasses.

Returns: string

Implements Problem< IntIntSolution >.

◆ getOptimizationDirection()

int BPP::getOptimizationDirection ( const int i ) const

overridevirtual

Gets the optimization direction of the problem. For the BPP is should always be Minimize.

Parameters

i

Returns: int

Implements Problem< IntIntSolution >.

◆ getUpperLimit()

float BPP::getUpperLimit ( int i ) const

overridevirtual

Returns the upper limit of the variable i In this case, the upper limit is the number of items - 1.

Parameters

i

Returns: float

Implements Problem< IntIntSolution >.

◆ readData()

void BPP::readData ( const string & path )

override

Reads the data from the file in the path. The file should contain a proper BPP instance with the following format: nItems Q w0 w1 ... wn-1.

Parameters

path

◆ setCapacity()

void BPP::setCapacity ( int Q )

Updates the capacity of the instance.

Parameters

Q

◆ to_json()

json BPP::to_json ( ) const

overridevirtual

Generates a JSON object with the information of the BPP problem

Returns

Reimplemented from Problem< IntIntSolution >.

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

include/dignea/problems/BPP.h
src/dignea/problems/BPP.cpp

Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ BPP() [1/3]

◆ BPP() [2/3]

◆ BPP() [3/3]

Member Function Documentation

◆ createSolution() [1/2]

◆ createSolution() [2/2]

◆ evaluate()

◆ evaluateConstraints()

◆ getLowerLimit()

◆ getName()

◆ getOptimizationDirection()

◆ getUpperLimit()

◆ readData()

◆ setCapacity()

◆ to_json()