keel.Algorithms.Rule_Learning.Ripper

Class Mask

java.lang.Object

keel.Algorithms.Rule_Learning.Ripper.Mask

public class Mask
extends java.lang.Object

Representation of a mask over a MyDataset. It allows to select a given set of entries without changing the MyDataset. In fact, it acts as a multiplexer over the MyDataset's entries. It also provides a cursor over those elements.

Since:

JDK1.2

Version:

1.1

Author:

Written by Alberto Fernández (University of Granada) 01/07/2008, Modified by Xavi Solé (La Salle, Ramón Llull University - Barcelona) 03/12/2008

Constructor Summary

Constructors

Constructor and Description
Mask(int size) Constructs a Mask of a given length.
Mask(int size, boolean initial) Constructs a Mask of a given length The cursor is set atBegin (that's a non valid position and it will be necessary a next() to reach the first active position).

Method Summary

Modifier and Type	Method and Description
Mask	and(Mask m) Returns the mask that it's the outcome of the bolean operation 'and' between this and a given mask.
void	change(int i) Changes the value of a given position (if it was activated, it is now deactivated and vicecersa).
Mask	complement() Returns a complementary mask of this mask (the activated entries of this mask are deactivated and viceversa).
Mask	copy() Returns a copy of this Mask
void	copyTo(Mask replicate) Copies this Mask into another Mask
int	getIndex() Returns the position pointed by the cursors.
int	getnActive() Return the number of active entries
boolean	isActive(int i) Returns wether a given entry is active or not
boolean	next() Advances the cursor to the next active entry.
Mask	or(Mask m) Returns the mask that it's the outcome of the bolean operation 'or' between this and a given mask.
void	reset() Deactivates the entry pointed by the cursor
void	reset(int i) Deactivates the value of a given position.
void	resetIndex() Sets the cursor at atBegin (that's a non valid position and it will be necessary a next() to reach the first active position).
void	set(int i) Activates the value of a given position.
void	set(int i, boolean value) Sets the states (activated or deactivated) of a given position.
Mask[]	split(double pct, Randomize rand) Splits, at random, this mask in two new masks

Methods inherited from class java.lang.Object

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

Constructor Detail

Mask

public Mask(int size)

Constructs a Mask of a given length. By default, it actives all entries. The cursor is set atBegin (that's a non valid position and it will be necessary a next() to reach the first active position).

Parameters:

size - int the Mask's length

Mask

public Mask(int size,
            boolean initial)

Constructs a Mask of a given length The cursor is set atBegin (that's a non valid position and it will be necessary a next() to reach the first active position).

Parameters:

size - int the Mask's length

initial - boolean initial value of the all entries

Method Detail

copy

public Mask copy()

Returns a copy of this Mask

Returns:

a copy of this Mask

copyTo

public void copyTo(Mask replicate)

Copies this Mask into another Mask

Parameters:

replicate - Mask a future copy of this Mask

isActive

public boolean isActive(int i)

Returns wether a given entry is active or not

Parameters:

i - int the index of the entry

Returns:

true if a given entry is active

reset

public void reset()

Deactivates the entry pointed by the cursor

change

public void change(int i)

Changes the value of a given position (if it was activated, it is now deactivated and vicecersa).

Parameters:

i - int number of entry to change

set

public void set(int i)

Activates the value of a given position.

Parameters:

i - int number of entry to active

reset

public void reset(int i)

Deactivates the value of a given position.

Parameters:

i - int number of entry to deactive

set

public void set(int i,
                boolean value)

Sets the states (activated or deactivated) of a given position.

Parameters:

i - int number of entry to set

value - boolean new value for the entry

complement

public Mask complement()

Returns a complementary mask of this mask (the activated entries of this mask are deactivated and viceversa).

Returns:

a complementary mask of this mask.

and

public Mask and(Mask m)

Returns the mask that it's the outcome of the bolean operation 'and' between this and a given mask.

Parameters:

m - Mask the other mask

Returns:

(this & m)

or

public Mask or(Mask m)

Returns the mask that it's the outcome of the bolean operation 'or' between this and a given mask.

Parameters:

m - Mask the other mask

Returns:

(this | m)

getnActive

public int getnActive()

Return the number of active entries

Returns:

the number of active entries

next

public boolean next()

Advances the cursor to the next active entry. If the cursor reach the end of the mask, it returns false.

Returns:

false if the cursor has reached the end of the mask.

getIndex

public int getIndex()

Returns the position pointed by the cursors.

Returns:

the position pointed by the cursors.

resetIndex

public void resetIndex()

Sets the cursor at atBegin (that's a non valid position and it will be necessary a next() to reach the first active position).

split

public Mask[] split(double pct,
                    Randomize rand)

Splits, at random, this mask in two new masks

Parameters:

pct - double spliting ratio, the length of the first outcome mask will be pct*|this|

rand - Randomize random number generator

Returns:

two masks ([0] || [1] = this) (the [0] has a length: (pct*|this|).