org.apache.datasketches.pig.frequencies

Class FrequentStringsSketchToEstimates

java.lang.Object

org.apache.pig.EvalFunc<org.apache.pig.data.DataBag>

org.apache.datasketches.pig.frequencies.FrequentStringsSketchToEstimates

public class FrequentStringsSketchToEstimates
extends org.apache.pig.EvalFunc<org.apache.pig.data.DataBag>

This UDF converts a FrequentItemsSketch<String> to estimates: {(item, estimate, upper bound, lower bound), ...}

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.pig.EvalFunc

org.apache.pig.EvalFunc.SchemaType

Field Summary

Fields inherited from class org.apache.pig.EvalFunc

log, pigLogger, reporter, returnType

Constructor Summary

Constructors

Constructor and Description
FrequentStringsSketchToEstimates() Instantiate UDF with default error type
FrequentStringsSketchToEstimates(String errorType) Instantiate UDF with given error type

Method Summary

Modifier and Type	Method and Description
org.apache.pig.data.DataBag	exec(org.apache.pig.data.Tuple input)
org.apache.pig.impl.logicalLayer.schema.Schema	outputSchema(org.apache.pig.impl.logicalLayer.schema.Schema inputSchema)

Methods inherited from class org.apache.pig.EvalFunc

allowCompileTimeCalculation, finish, getArgToFuncMapping, getCacheFiles, getInputSchema, getLoadCaster, getLogger, getPigLogger, getReporter, getReturnType, getSchemaName, getSchemaType, getShipFiles, isAsynchronous, needEndOfAllInputProcessing, progress, setEndOfAllInput, setInputSchema, setPigLogger, setReporter, setUDFContextSignature, warn

Methods inherited from class java.lang.Object

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

Constructor Detail

FrequentStringsSketchToEstimates

public FrequentStringsSketchToEstimates()

Instantiate UDF with default error type

FrequentStringsSketchToEstimates

public FrequentStringsSketchToEstimates(String errorType)

Instantiate UDF with given error type

Parameters:

errorType - string representation of error type

Method Detail

exec

public org.apache.pig.data.DataBag exec(org.apache.pig.data.Tuple input)
                                 throws IOException

Specified by:

exec in class org.apache.pig.EvalFunc<org.apache.pig.data.DataBag>

Throws:

IOException

outputSchema

public org.apache.pig.impl.logicalLayer.schema.Schema outputSchema(org.apache.pig.impl.logicalLayer.schema.Schema inputSchema)

Overrides:

outputSchema in class org.apache.pig.EvalFunc<org.apache.pig.data.DataBag>