com.datadoghq.sketch.ddsketch.mapping

Class QuarticallyInterpolatedMapping

java.lang.Object

com.datadoghq.sketch.ddsketch.mapping.QuarticallyInterpolatedMapping

All Implemented Interfaces:

IndexMapping

public class QuarticallyInterpolatedMapping
extends java.lang.Object

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 quartically interpolating the logarithm in-between.

The optimal polynomial coefficients can be calculated using the method described in CubicallyInterpolatedMapping.

Constructor Summary

Constructors

Constructor and Description
QuarticallyInterpolatedMapping(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

QuarticallyInterpolatedMapping

public QuarticallyInterpolatedMapping(double relativeAccuracy)

Method Detail

index

public final int index(double value)

Specified by:

index in interface IndexMapping

value

public final 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 final 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

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

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