org.apache.beam.sdk.extensions.sketching

Class TDigestQuantiles.TDigestQuantilesFn

java.lang.Object

org.apache.beam.sdk.transforms.Combine.CombineFn<java.lang.Double,com.tdunning.math.stats.MergingDigest,com.tdunning.math.stats.MergingDigest>

org.apache.beam.sdk.extensions.sketching.TDigestQuantiles.TDigestQuantilesFn

All Implemented Interfaces:

java.io.Serializable, CombineFnBase.GlobalCombineFn<java.lang.Double,com.tdunning.math.stats.MergingDigest,com.tdunning.math.stats.MergingDigest>, HasDisplayData

Enclosing class:

TDigestQuantiles

public static class TDigestQuantiles.TDigestQuantilesFn
extends Combine.CombineFn<java.lang.Double,com.tdunning.math.stats.MergingDigest,com.tdunning.math.stats.MergingDigest>

Implements the Combine.CombineFn of TDigestQuantiles transforms.

See Also:

Serialized Form

Method Summary

Modifier and Type	Method and Description
com.tdunning.math.stats.MergingDigest	addInput(com.tdunning.math.stats.MergingDigest accum, java.lang.Double value) Adds the given input value to the given accumulator, returning the new accumulator value.
static TDigestQuantiles.TDigestQuantilesFn	create(double compression) Returns TDigestQuantiles.TDigestQuantilesFn combiner with the given compression factor.
com.tdunning.math.stats.MergingDigest	createAccumulator() Returns a new, mutable accumulator value, representing the accumulation of zero input values.
com.tdunning.math.stats.MergingDigest	extractOutput(com.tdunning.math.stats.MergingDigest accum) Output the whole structure so it can be queried, reused or stored easily.
java.lang.reflect.TypeVariable<?>	getAccumTVariable() Returns the TypeVariable of AccumT.
Coder<com.tdunning.math.stats.MergingDigest>	getAccumulatorCoder(CoderRegistry registry, Coder inputCoder) Returns the Coder to use for accumulator AccumT values, or null if it is not able to be inferred.
Coder<com.tdunning.math.stats.MergingDigest>	getDefaultOutputCoder(CoderRegistry registry, Coder inputCoder) Returns the Coder to use by default for output OutputT values, or null if it is not able to be inferred.
java.lang.String	getIncompatibleGlobalWindowErrorMessage() Returns the error message for not supported default values in Combine.globally().
java.lang.reflect.TypeVariable<?>	getInputTVariable() Returns the TypeVariable of InputT.
java.lang.reflect.TypeVariable<?>	getOutputTVariable() Returns the TypeVariable of OutputT.
com.tdunning.math.stats.MergingDigest	mergeAccumulators(java.lang.Iterable<com.tdunning.math.stats.MergingDigest> accumulators) Returns an accumulator representing the accumulation of all the input values accumulated in the merging accumulators.
void	populateDisplayData(DisplayData.Builder builder) Register display data for the given transform or component.

Methods inherited from class org.apache.beam.sdk.transforms.Combine.CombineFn

apply, compact, defaultValue, getOutputType

Methods inherited from class java.lang.Object

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

Method Detail

create

public static TDigestQuantiles.TDigestQuantilesFn create(double compression)

Returns TDigestQuantiles.TDigestQuantilesFn combiner with the given compression factor.

Keep in mind that a compression factor cf of c guarantees a relative error less than 3/c at mid quantiles.
The accuracy will always be significantly less than 1% at extreme quantiles.

Parameters:

compression - the bound value for centroid and digest sizes.

createAccumulator

public com.tdunning.math.stats.MergingDigest createAccumulator()

Description copied from class: Combine.CombineFn

Returns a new, mutable accumulator value, representing the accumulation of zero input values.

Specified by:

createAccumulator in class Combine.CombineFn<java.lang.Double,com.tdunning.math.stats.MergingDigest,com.tdunning.math.stats.MergingDigest>

addInput

public com.tdunning.math.stats.MergingDigest addInput(com.tdunning.math.stats.MergingDigest accum,
                                                      java.lang.Double value)

Description copied from class: Combine.CombineFn

Adds the given input value to the given accumulator, returning the new accumulator value.

For efficiency, the input accumulator may be modified and returned.

Specified by:

addInput in class Combine.CombineFn<java.lang.Double,com.tdunning.math.stats.MergingDigest,com.tdunning.math.stats.MergingDigest>

extractOutput

public com.tdunning.math.stats.MergingDigest extractOutput(com.tdunning.math.stats.MergingDigest accum)

Output the whole structure so it can be queried, reused or stored easily.

Specified by:

extractOutput in class Combine.CombineFn<java.lang.Double,com.tdunning.math.stats.MergingDigest,com.tdunning.math.stats.MergingDigest>

mergeAccumulators

public com.tdunning.math.stats.MergingDigest mergeAccumulators(java.lang.Iterable<com.tdunning.math.stats.MergingDigest> accumulators)

Description copied from class: Combine.CombineFn

Returns an accumulator representing the accumulation of all the input values accumulated in the merging accumulators.

May modify any of the argument accumulators. May return a fresh accumulator, or may return one of the (modified) argument accumulators.

Specified by:

mergeAccumulators in class Combine.CombineFn<java.lang.Double,com.tdunning.math.stats.MergingDigest,com.tdunning.math.stats.MergingDigest>

getAccumulatorCoder

public Coder<com.tdunning.math.stats.MergingDigest> getAccumulatorCoder(CoderRegistry registry,
                                                                        Coder inputCoder)

Description copied from interface: CombineFnBase.GlobalCombineFn

Returns the Coder to use for accumulator AccumT values, or null if it is not able to be inferred.

By default, uses the knowledge of the Coder being used for InputT values and the enclosing Pipeline's CoderRegistry to try to infer the Coder for AccumT values.

This is the Coder used to send data through a communication-intensive shuffle step, so a compact and efficient representation may have significant performance benefits.

Specified by:

getAccumulatorCoder in interface CombineFnBase.GlobalCombineFn<java.lang.Double,com.tdunning.math.stats.MergingDigest,com.tdunning.math.stats.MergingDigest>

getDefaultOutputCoder

public Coder<com.tdunning.math.stats.MergingDigest> getDefaultOutputCoder(CoderRegistry registry,
                                                                          Coder inputCoder)

Description copied from interface: CombineFnBase.GlobalCombineFn

Returns the Coder to use by default for output OutputT values, or null if it is not able to be inferred.

By default, uses the knowledge of the Coder being used for input InputT values and the enclosing Pipeline's CoderRegistry to try to infer the Coder for OutputT values.

Specified by:

getDefaultOutputCoder in interface CombineFnBase.GlobalCombineFn<java.lang.Double,com.tdunning.math.stats.MergingDigest,com.tdunning.math.stats.MergingDigest>

populateDisplayData

public void populateDisplayData(DisplayData.Builder builder)

Register display data for the given transform or component.

populateDisplayData(DisplayData.Builder) is invoked by Pipeline runners to collect display data via DisplayData.from(HasDisplayData). Implementations may call super.populateDisplayData(builder) in order to register display data in the current namespace, but should otherwise use subcomponent.populateDisplayData(builder) to use the namespace of the subcomponent.

By default, does not register any display data. Implementors may override this method to provide their own display data.

Specified by:

populateDisplayData in interface HasDisplayData

Parameters:

builder - The builder to populate with display data.

See Also:

HasDisplayData

getIncompatibleGlobalWindowErrorMessage

public java.lang.String getIncompatibleGlobalWindowErrorMessage()

Description copied from interface: CombineFnBase.GlobalCombineFn

Returns the error message for not supported default values in Combine.globally().

Specified by:

getIncompatibleGlobalWindowErrorMessage in interface CombineFnBase.GlobalCombineFn<InputT,AccumT,OutputT>

getInputTVariable

public java.lang.reflect.TypeVariable<?> getInputTVariable()

Returns the TypeVariable of InputT.

getAccumTVariable

public java.lang.reflect.TypeVariable<?> getAccumTVariable()

Returns the TypeVariable of AccumT.

getOutputTVariable

public java.lang.reflect.TypeVariable<?> getOutputTVariable()

Returns the TypeVariable of OutputT.