jcgp.backend.function

Class FunctionSet

java.lang.Object

jcgp.backend.function.FunctionSet

Direct Known Subclasses:

DigitalCircuitFunctions, SymbolicRegressionFunctions, TravellingSalesmanFunctions

public abstract class FunctionSet
extends java.lang.Object

FunctionSet encapsulates a group of functions. This is done to simplify the implementation of problem types.

FunctionSet contains a variety of useful methods for acquiring general information, such as the maximum arity across all functions and the total number of functions.

In addition, FunctionSet offers the ability to enable and disable functions. Accessing the functions through getAllowedFunction() will return allowed functions only, providing an easy way to control which functions can be used in mutations.

An implementation of FunctionSet must simply use its constructor to set the name field and use registerFunctions() to add the required functions.

Author:

Eduardo Pedroni

Constructor Summary

Constructors

Constructor and Description
FunctionSet()

Method Summary

Modifier and Type	Method and Description
void	disableFunction(int index) Disables the indexed function.
void	enableFunction(int index) Disables the indexed function.
Function	getAllowedFunction(int index) Returns an allowed function.
int	getAllowedFunctionCount()
Function	getFunction(int index) Returns a function from the complete collection, enabled or disabled alike.
int	getMaxArity() Computes and returns the maximum arity out of all enabled functions.
int	getTotalFunctionCount()
boolean	isEnabled(Function function) Checks if a specified function is enabled.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FunctionSet

public FunctionSet()

Method Detail

getAllowedFunctionCount

public int getAllowedFunctionCount()

Returns:

the number of currently allowed functions.

getTotalFunctionCount

public int getTotalFunctionCount()

Returns:

the total number of functions, including disabled ones.

getAllowedFunction

public Function getAllowedFunction(int index)

Returns an allowed function. This throws an ArrayIndexOutOfBoundsException if the supplied index is beyond the count of allowed functions.

Parameters:

index - the allowed function index.

Returns:

the allowed function object.

getFunction

public Function getFunction(int index)

Returns a function from the complete collection, enabled or disabled alike. This throws an ArrayIndexOutOfBoundsException if the supplied index is beyond the count of allowed functions.

Parameters:

index - the function index.

Returns:

the function object.

getMaxArity

public int getMaxArity()

Computes and returns the maximum arity out of all enabled functions.

Returns:

the problem's current maximum arity.

disableFunction

public void disableFunction(int index)

Disables the indexed function. If the function is already disabled, this does nothing.

Parameters:

index - the function to disable.

enableFunction

public void enableFunction(int index)

Disables the indexed function. If the function is already enabled, this does nothing.

Parameters:

index - the function to disable.

isEnabled

public boolean isEnabled(Function function)

Checks if a specified function is enabled. If the function does not belong in the FunctionSet, this returns false.

Parameters:

function - the function to check.

Returns:

true if the function is enabled.