eu.stratosphere.example.java.record.kmeans.udfs

Class CoordVector

java.lang.Object

eu.stratosphere.example.java.record.kmeans.udfs.CoordVector

All Implemented Interfaces:

IOReadableWritable, Key, Value, Serializable, Comparable<Key>

public final class CoordVector
extends Object
implements Key

Implements a feature vector as a multi-dimensional point. Coordinates of that point (= the features) are stored as double values. The distance between two feature vectors is the Euclidian distance between the points.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
CoordVector() Initializes a blank coordinate vector.
CoordVector(double[] coordinates) Initializes a coordinate vector.
CoordVector(Double[] coordinates) Initializes a coordinate vector.

Method Summary

Methods

Modifier and Type	Method and Description
int	compareTo(Key o) Compares this coordinate vector to another key.
double	computeEuclidianDistance(CoordVector cv) Computes the Euclidian distance between this coordinate vector and a second coordinate vector.
double[]	getCoordinates() Returns the coordinate vector of a multi-dimensional point.
void	read(DataInput in)
void	setCoordinates(double[] coordinates) Sets the coordinate vector of a multi-dimensional point.
void	write(DataOutput out)

Methods inherited from class java.lang.Object

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

Methods inherited from interface eu.stratosphere.types.Key

equals, hashCode

Constructor Detail

CoordVector

public CoordVector()

Initializes a blank coordinate vector. Required for deserialization!

CoordVector

public CoordVector(Double[] coordinates)

Initializes a coordinate vector.

Parameters:

coordinates - The coordinate vector of a multi-dimensional point.

CoordVector

public CoordVector(double[] coordinates)

Initializes a coordinate vector.

Parameters:

coordinates - The coordinate vector of a multi-dimensional point.

Method Detail

getCoordinates

public double[] getCoordinates()

Returns the coordinate vector of a multi-dimensional point.

Returns:

The coordinate vector of a multi-dimensional point.

setCoordinates

public void setCoordinates(double[] coordinates)

Sets the coordinate vector of a multi-dimensional point.

Parameters:

point - The dimension values of the point.

computeEuclidianDistance

public double computeEuclidianDistance(CoordVector cv)

Computes the Euclidian distance between this coordinate vector and a second coordinate vector.

Parameters:

cv - The coordinate vector to which the distance is computed.

Returns:

The Euclidian distance to coordinate vector cv. If cv has a different length than this coordinate vector, -1 is returned.

read

public void read(DataInput in)
          throws IOException

Specified by:

read in interface IOReadableWritable

Throws:

IOException

write

public void write(DataOutput out)
           throws IOException

Specified by:

write in interface IOReadableWritable

Throws:

IOException

compareTo

public int compareTo(Key o)

Compares this coordinate vector to another key.

Specified by:

compareTo in interface Comparable<Key>

Returns:

-1 if the other key is not of type CoordVector. If the other key is also a CoordVector but its length differs from this coordinates vector, -1 is return if this coordinate vector is smaller and 1 if it is larger. If both coordinate vectors have the same length, the coordinates of both are compared. If a coordinate of this coordinate vector is smaller than the corresponding coordinate of the other vector -1 is returned and 1 otherwise. If all coordinates are identical 0 is returned.