com.datadoghq.sketch.ddsketch.mapping

Class BitwiseLinearlyInterpolatedMapping

java.lang.Object

com.datadoghq.sketch.ddsketch.mapping.BitwiseLinearlyInterpolatedMapping

All Implemented Interfaces:

IndexMapping

public class BitwiseLinearlyInterpolatedMapping
extends java.lang.Object
implements IndexMapping

A fast IndexMapping that approximates the memory-optimal one (namely LogarithmicMapping) by extracting the floor value of the logarithm to the base 2 from the binary representations of floating-point values and linearly interpolating the logarithm in-between using, again, the binary representation.

Note that this mapping, while fast, might be highly memory inefficient as it only works for a discrete set of relative accuracies and will fall back to the largest possible one that is less than the requested accuracy (which can be as low as half of it, in the worst case).

Constructor Summary

Constructors

Constructor and Description
BitwiseLinearlyInterpolatedMapping(double relativeAccuracy)

Method Summary

Modifier and Type	Method and Description
void	encode(Output output)
boolean	equals(java.lang.Object o)
int	hashCode()
int	index(double value)
double	lowerBound(int index)
double	maxIndexableValue()
double	minIndexableValue()
double	relativeAccuracy()
void	serialize(Serializer serializer)
int	serializedSize()
double	upperBound(int index)
double	value(int index)

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.datadoghq.sketch.ddsketch.mapping.IndexMapping

decode

Constructor Detail

BitwiseLinearlyInterpolatedMapping

public BitwiseLinearlyInterpolatedMapping(double relativeAccuracy)

Method Detail

index

public int index(double value)

Specified by:

index in interface IndexMapping

value

public double value(int index)

Specified by:

value in interface IndexMapping

lowerBound

public double lowerBound(int index)

Specified by:

lowerBound in interface IndexMapping

upperBound

public double upperBound(int index)

Specified by:

upperBound in interface IndexMapping

relativeAccuracy

public double relativeAccuracy()

Specified by:

relativeAccuracy in interface IndexMapping

minIndexableValue

public double minIndexableValue()

Specified by:

minIndexableValue in interface IndexMapping

maxIndexableValue

public double maxIndexableValue()

Specified by:

maxIndexableValue in interface IndexMapping

encode

public void encode(Output output)
            throws java.io.IOException

Specified by:

encode in interface IndexMapping

Throws:

java.io.IOException

serializedSize

public int serializedSize()

Specified by:

serializedSize in interface IndexMapping

serialize

public void serialize(Serializer serializer)

Specified by:

serialize in interface IndexMapping

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object