Package elki.data

Class DoubleVector

java.lang.Object

elki.data.DoubleVector

All Implemented Interfaces:

FeatureVector<java.lang.Number>, NumberVector, SpatialComparable

public class DoubleVector
extends java.lang.Object
implements NumberVector

Vector type using double[] storage for real numbers.

Since:

0.1

Author:

Arthur Zimek

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	DoubleVector.Factory	Factory for Double vectors.
static class	DoubleVector.ShortSerializer	Serialization class for dense double vectors with up to Short.MAX_VALUE dimensions, by using a short for storing the dimensionality.
static class	DoubleVector.SmallSerializer	Serialization class for dense double vectors with up to 127 dimensions, by using a byte for storing the dimensionality.
static class	DoubleVector.VariableSerializer	Serialization class for variable dimensionality by using VarInt encoding.

Field Summary

Fields

Modifier and Type	Field	Description
static ByteBufferSerializer<DoubleVector>	BYTE_SERIALIZER	Serializer for up to 127 dimensions.
static DoubleVector.Factory	FACTORY	Static factory instance.
static ByteBufferSerializer<DoubleVector>	SHORT_SERIALIZER	Serializer for up to 2^15-1 dimensions.
private double[]	values	Stores the values of the real vector.
static ByteBufferSerializer<DoubleVector>	VARIABLE_SERIALIZER	Serializer using varint encoding.

Fields inherited from interface elki.data.FeatureVector

TYPE

Fields inherited from interface elki.data.NumberVector

ATTRIBUTE_SEPARATOR, FIELD, FIELD_1D, FIELD_2D, VARIABLE_LENGTH

Constructor Summary

Constructors

Modifier	Constructor	Description
	DoubleVector(double[] values)	Create a DoubleVector consisting of the given double values.
private	DoubleVector(double[] values, boolean nocopy)	Private constructor.

Method Summary

Modifier and Type	Method	Description
static DoubleVector	copy(double[] vals)	Copy a double array into a new vector.
double	doubleValue(int dimension)	Returns the value in the specified dimension as double.
int	getDimensionality()	The dimensionality of the vector space where of this FeatureVector of V is an element.
long	longValue(int dimension)	Returns the value in the specified dimension as long.
double[]	toArray()	Returns a double array copy of this vector.
java.lang.String	toString()	Returns a String representation of the FeatureVector of V as a line that is suitable to be printed in a sequential file.
static DoubleVector	wrap(double[] vals)	Wrap a double array as vector (without copying).

Methods inherited from class java.lang.Object

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

Methods inherited from interface elki.data.NumberVector

byteValue, floatValue, getMax, getMin, getValue, intValue, shortValue

Field Detail

FACTORY

public static final DoubleVector.Factory FACTORY

Static factory instance.

BYTE_SERIALIZER

public static final ByteBufferSerializer<DoubleVector> BYTE_SERIALIZER

Serializer for up to 127 dimensions.

SHORT_SERIALIZER

public static final ByteBufferSerializer<DoubleVector> SHORT_SERIALIZER

Serializer for up to 2^15-1 dimensions.

VARIABLE_SERIALIZER

public static final ByteBufferSerializer<DoubleVector> VARIABLE_SERIALIZER

Serializer using varint encoding.

values

private final double[] values

Stores the values of the real vector.

Constructor Detail

DoubleVector

private DoubleVector(double[] values,
                     boolean nocopy)

Private constructor. NOT for public use.

Parameters:

values - Values to use

nocopy - Flag to not copy the array

DoubleVector

public DoubleVector(double[] values)

Create a DoubleVector consisting of the given double values.

Parameters:

values - the values to be set as values of the DoubleVector

Method Detail

getDimensionality

public int getDimensionality()

Description copied from interface: FeatureVector

The dimensionality of the vector space where of this FeatureVector of V is an element.

Specified by:

getDimensionality in interface FeatureVector<java.lang.Number>

Specified by:

getDimensionality in interface SpatialComparable

Returns:

the number of dimensions of this FeatureVector of V

doubleValue

public double doubleValue(int dimension)

Description copied from interface: NumberVector

Returns the value in the specified dimension as double.

Note: this might seem redundant with respect to getValue(dim).doubleValue(), but usually this is much more efficient due to boxing/unboxing cost.

Specified by:

doubleValue in interface NumberVector

Parameters:

dimension - the desired dimension, where 0 ≤ dimension < this.getDimensionality()

Returns:

the value in the specified dimension

longValue

public long longValue(int dimension)

Description copied from interface: NumberVector

Returns the value in the specified dimension as long.

Note: this might seem redundant with respect to getValue(dim).longValue(), but usually this is much more efficient due to boxing/unboxing cost.

Specified by:

longValue in interface NumberVector

Parameters:

dimension - the desired dimension, where 0 ≤ dimension < this.getDimensionality()

Returns:

the value in the specified dimension

toArray

public double[] toArray()

Description copied from interface: NumberVector

Returns a double array copy of this vector.

Specified by:

toArray in interface NumberVector

Returns:

Copy as double[]

toString

public java.lang.String toString()

Description copied from interface: FeatureVector

Returns a String representation of the FeatureVector of V as a line that is suitable to be printed in a sequential file.

Specified by:

toString in interface FeatureVector<java.lang.Number>

Overrides:

toString in class java.lang.Object

Returns:

a String representation of the FeatureVector of V

copy

public static DoubleVector copy(double[] vals)

Copy a double array into a new vector.

Parameters:

vals - Values

Returns:

Wrapped vector

wrap

public static DoubleVector wrap(double[] vals)

Wrap a double array as vector (without copying).

Note: modifying the array afterwards can lead to problems if the data has, e.g., been added to an index, which relies on them being immutable!

Parameters:

vals - Values

Returns:

Wrapped vector