edu.ucla.sspace.vector

Class MaskedDoubleVectorView

java.lang.Object

edu.ucla.sspace.vector.MaskedDoubleVectorView

All Implemented Interfaces:

DoubleVector, Vector<Double>, Serializable

Direct Known Subclasses:

MaskedSparseDoubleVectorView

public class MaskedDoubleVectorView
extends Object
implements DoubleVector

A decorator that masked view of a Vector through the use of a mapping from new column indices to original column indices. The size of the new vector is based on the number of valid mappings.

Author:

Keith Stevens

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	isImmutable Whether the vector data backing this instance is immutable
protected double	magnitude The magnitude of the vector or -1 if the value is currently invalid needs to be recomputed
protected boolean	updated Set to true whenever the vector's values have been modified.
protected Vector	vector The actual vector this ViewDoubleAsDoubleVector is decorating.
protected int	vectorLength A fixed length for this Vector.
protected int	vectorOffset The index at which the values vector are stored.

Constructor Summary

Constructors

Constructor and Description
MaskedDoubleVectorView(DoubleVector v, int[] columnMask) Creates a new DoubleVector view of the data in the provided DoubleVector.

Method Summary

Methods

Modifier and Type	Method and Description
double	add(int index, double delta) Changes the value in this vector by a specified amount (optional operation).
double	get(int index) Returns the value of this vector at the given index.
protected int	getIndex(int index) Returns the new index for a given column, or -1 if the column is not mapped.
DoubleVector	getOriginalVector() Returns the original vector that this view is wrapping.
Double	getValue(int index) Return the value of the vector at the given index as a Number.
int	length() Return the size of the Vector.
double	magnitude() Returns the magnitude of this vector
void	set(int index, double value) Sets the length in this vector (optional operation).
void	set(int index, Number value) Throws UnsupportedOperationException if called
double[]	toArray() Returns a double array representing this vector.
String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.ucla.sspace.vector.Vector

equals, hashCode, magnitude, set

Field Detail

updated

protected boolean updated

Set to true whenever the vector's values have been modified.

isImmutable

protected final boolean isImmutable

Whether the vector data backing this instance is immutable

vector

protected final Vector vector

The actual vector this ViewDoubleAsDoubleVector is decorating.

vectorLength

protected final int vectorLength

A fixed length for this Vector. This length may be longer or less than that of vector.

vectorOffset

protected final int vectorOffset

The index at which the values vector are stored.

magnitude

protected double magnitude

The magnitude of the vector or -1 if the value is currently invalid needs to be recomputed

Constructor Detail

MaskedDoubleVectorView

public MaskedDoubleVectorView(DoubleVector v,
                      int[] columnMask)

Creates a new DoubleVector view of the data in the provided DoubleVector.

Parameters:

v - the DoubleVector to view as containing double data.

columnMask - A mapping from new indices to old indices.

Method Detail

getIndex

protected int getIndex(int index)

Returns the new index for a given column, or -1 if the column is not mapped.

add

public double add(int index,
         double delta)

Changes the value in this vector by a specified amount (optional operation). If there is not a value set at index, delta should be set to the actual value.

Specified by:

add in interface DoubleVector

Parameters:

index - index to change.

delta - the amount to change by.

Returns:

the resulting value at the index

set

public void set(int index,
       double value)

Sets the length in this vector (optional operation).

Specified by:

set in interface DoubleVector

Parameters:

index - index to set.

value - value to set in the vector.

get

public double get(int index)

Returns the value of this vector at the given index.

Specified by:

get in interface DoubleVector

Parameters:

index - index to retrieve.

Returns:

value at index.

getValue

public Double getValue(int index)

Return the value of the vector at the given index as a Number.

Specified by:

getValue in interface DoubleVector

Specified by:

getValue in interface Vector<Double>

Parameters:

index - index to retrieve.

Returns:

value at index.

toArray

public double[] toArray()

Returns a double array representing this vector. The returned array will be "safe" in that no changes to the array will be reflected in the vector, and likewise for changes to to the vector. The caller is thus free to modify the returned array.

Specified by:

toArray in interface DoubleVector

Returns:

a double array of this vector.

length

public int length()

Return the size of the Vector.

Specified by:

length in interface Vector<Double>

Returns:

size of the vector.

getOriginalVector

public DoubleVector getOriginalVector()

Returns the original vector that this view is wrapping. This is primarily so that Vectors.copyOf can create a copy of the real vector.

set

public void set(int index,
       Number value)

Throws UnsupportedOperationException if called

Specified by:

set in interface Vector<T extends Number>

Parameters:

index - index to set.

value - value to set in the vector.

magnitude

public double magnitude()

Returns the magnitude of this vector

Specified by:

magnitude in interface Vector<T extends Number>

toString

public String toString()

Overrides:

toString in class Object