org.apache.beam.sdk.extensions.sketching

Class TDigestQuantiles.PerKeyDigest<K>

java.lang.Object

org.apache.beam.sdk.transforms.PTransform<PCollection<KV<K,java.lang.Double>>,PCollection<KV<K,com.tdunning.math.stats.MergingDigest>>>

org.apache.beam.sdk.extensions.sketching.TDigestQuantiles.PerKeyDigest<K>

All Implemented Interfaces:

java.io.Serializable, HasDisplayData

Enclosing class:

TDigestQuantiles

public abstract static class TDigestQuantiles.PerKeyDigest<K>
extends PTransform<PCollection<KV<K,java.lang.Double>>,PCollection<KV<K,com.tdunning.math.stats.MergingDigest>>>

Implementation of TDigestQuantiles.perKey().

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.beam.sdk.transforms.PTransform

name

Constructor Summary

Constructors

Constructor and Description
PerKeyDigest()

Method Summary

Modifier and Type	Method and Description
PCollection<KV<K,com.tdunning.math.stats.MergingDigest>>	expand(PCollection<KV<K,java.lang.Double>> input) Override this method to specify how this PTransform should be expanded on the given InputT.
TDigestQuantiles.PerKeyDigest<K>	withCompression(double cf) Sets the compression factor cf.

Methods inherited from class org.apache.beam.sdk.transforms.PTransform

getAdditionalInputs, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, populateDisplayData, toString, validate

Methods inherited from class java.lang.Object

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

Constructor Detail

PerKeyDigest

public PerKeyDigest()

Method Detail

withCompression

public TDigestQuantiles.PerKeyDigest<K> withCompression(double cf)

Sets the compression factor cf.

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:

cf - the bound value for centroid and digest sizes.

expand

public PCollection<KV<K,com.tdunning.math.stats.MergingDigest>> expand(PCollection<KV<K,java.lang.Double>> input)

Description copied from class: PTransform

Override this method to specify how this PTransform should be expanded on the given InputT.

NOTE: This method should not be called directly. Instead apply the PTransform should be applied to the InputT using the apply method.

Composite transforms, which are defined in terms of other transforms, should return the output of one of the composed transforms. Non-composite transforms, which do not apply any transforms internally, should return a new unbound output and register evaluators (via backend-specific registration methods).

Specified by:

expand in class PTransform<PCollection<KV<K,java.lang.Double>>,PCollection<KV<K,com.tdunning.math.stats.MergingDigest>>>