keel.Algorithms.Decision_Trees.M5

Class Function

java.lang.Object

keel.Algorithms.Decision_Trees.M5.Function

All Implemented Interfaces:

java.io.Serializable

public final class Function
extends java.lang.Object
implements java.io.Serializable

Class for handling a linear function.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Function() Constructs a function of constant value
Function(int attr) Constructs a function with one attribute
Function(M5Instances inst) Constucts a function with all attributes except the class in the inst

Method Summary

Modifier and Type	Method and Description
static Function	combine(Function f1, Function f2) Constructs a new function of which the variable list is a combination of those of two functions
Function	copy() Makes a copy of a function
static double[]	dVectorCopy(double[] a, int n) Copy the first n elements of the array a.
Results	errors(M5Instances inst) Evaluates a function
int	insignificant(double sdy, M5Instances inst) Detects the most insignificant variable in the funcion
static int[]	iVectorCombine(int[] list1, int[] list2) Combine two vectors in one maintaining an ascending order.
static int[]	iVectorCopy(int[] a, int n) Copy the first n elements of the array a.
double	predict(M5Instance instance) Returns the predicted value of instance i by a function
Function	remove(int j) Removes a term from the function
java.lang.String	toString(M5Instances inst, int startPoint) Converts a function to a string

Methods inherited from class java.lang.Object

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

Constructor Detail

Function

public Function()

Constructs a function of constant value

Function

public Function(M5Instances inst)

Constucts a function with all attributes except the class in the inst

Parameters:

inst - instances

Function

public Function(int attr)

Constructs a function with one attribute

Parameters:

attr - an attribute

Method Detail

copy

public final Function copy()

Makes a copy of a function

Returns:

the copy of the function

dVectorCopy

public static final double[] dVectorCopy(double[] a,
                                         int n)

Copy the first n elements of the array a.

Parameters:

a - array to copy.

n - number of elements copied. Element at position n is not included.

Returns:

New array with the first n elements of the array a.

iVectorCopy

public static final int[] iVectorCopy(int[] a,
                                      int n)

Copy the first n elements of the array a.

Parameters:

a - array to copy.

n - number of elements copied. Element at position n is not included.

Returns:

New array with the first n elements of the array a.

toString

public final java.lang.String toString(M5Instances inst,
                                       int startPoint)
                                throws java.lang.Exception

Converts a function to a string

Parameters:

inst - instances

startPoint - the starting point on the screen; used to feed line before reaching beyond 80 characters

Returns:

the converted string

Throws:

java.lang.Exception - if something goes wrong

combine

public static final Function combine(Function f1,
                                     Function f2)

Constructs a new function of which the variable list is a combination of those of two functions

Parameters:

f1 - function 1

f2 - function 2

Returns:

the newly constructed function

iVectorCombine

public static final int[] iVectorCombine(int[] list1,
                                         int[] list2)

Combine two vectors in one maintaining an ascending order.

Parameters:

list1 - first vector.

list2 - second vector.

Returns:

combiation of the two vector.

errors

public final Results errors(M5Instances inst)
                     throws java.lang.Exception

Evaluates a function

Parameters:

inst - instances

Returns:

the evaluation results

Throws:

java.lang.Exception - if something goes wrong

predict

public final double predict(M5Instance instance)

Returns the predicted value of instance i by a function

Parameters:

instance - instances

Returns:

the predicted value

insignificant

public final int insignificant(double sdy,
                               M5Instances inst)

Detects the most insignificant variable in the funcion

Parameters:

sdy - the standard deviation of the class variable

inst - instances

Returns:

the index of the most insignificant variable in the function

remove

public final Function remove(int j)

Removes a term from the function

Parameters:

j - the j-th index in the variable list in the function

Returns:

the new function with the term removed