org.apache.beam.sdk.extensions.sketching

Class SketchFrequencies.PerKeySketch<K,V>

java.lang.Object

org.apache.beam.sdk.transforms.PTransform<org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,V>>,org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,SketchFrequencies.Sketch<V>>>>

org.apache.beam.sdk.extensions.sketching.SketchFrequencies.PerKeySketch<K,V>

Type Parameters:

K - type of the keys mapping the elements

V - type of the values being combined per key

All Implemented Interfaces:

java.io.Serializable, org.apache.beam.sdk.transforms.display.HasDisplayData

Enclosing class:

SketchFrequencies

public abstract static class SketchFrequencies.PerKeySketch<K,V>
extends org.apache.beam.sdk.transforms.PTransform<org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,V>>,org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,SketchFrequencies.Sketch<V>>>>

Implementation of SketchFrequencies.perKey().

See Also:

Serialized Form

Field Summary

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

annotations, displayData, name, resourceHints

Constructor Summary

Constructors

Constructor and Description
PerKeySketch()

Method Summary

Modifier and Type	Method and Description
org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,SketchFrequencies.Sketch<V>>>	expand(org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,V>> input)
SketchFrequencies.PerKeySketch<K,V>	withConfidence(double conf) Sets the confidence value, i.e.
SketchFrequencies.PerKeySketch<K,V>	withRelativeError(double eps) Sets the relative error epsilon.

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

addAnnotation, compose, compose, getAdditionalInputs, getAnnotations, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, getResourceHints, populateDisplayData, setDisplayData, setResourceHints, toString, validate, validate

Methods inherited from class java.lang.Object

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

Constructor Detail

PerKeySketch

public PerKeySketch()

Method Detail

withRelativeError

public SketchFrequencies.PerKeySketch<K,V> withRelativeError(double eps)

Sets the relative error epsilon.

Keep in mind that the lower the epsilon value, the greater the width.

Parameters:

eps - the error relative to the total number of distinct elements

withConfidence

public SketchFrequencies.PerKeySketch<K,V> withConfidence(double conf)

Sets the confidence value, i.e. the probability that the relative error is lower or equal to epsilon.

Keep in mind that the greater the confidence, the greater the depth.

Parameters:

conf - the confidence in the result to not exceed the relative error

expand

public org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,SketchFrequencies.Sketch<V>>> expand(org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,V>> input)

Specified by:

expand in class org.apache.beam.sdk.transforms.PTransform<org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,V>>,org.apache.beam.sdk.values.PCollection<org.apache.beam.sdk.values.KV<K,SketchFrequencies.Sketch<V>>>>