com.espertech.esper.epl.agg.aggregator
Class AggregatorStddev

java.lang.Object
  com.espertech.esper.epl.agg.aggregator.AggregatorStddev

All Implemented Interfaces:

AggregationMethod

Direct Known Subclasses:

AggregatorStddevFilter

public class AggregatorStddev
extends java.lang.Object
implements AggregationMethod

Standard deviation always generates double-typed numbers.

Field Summary

protected double	mean
protected long	numDataPoints
protected double	qn

Constructor Summary

AggregatorStddev()

Method Summary

void	clear() Clear out the collection.
void	enter(java.lang.Object object) Apply the value as entering aggregation (entering window).
java.lang.Object	getValue() Returns the current value held.
java.lang.Class	getValueType() Returns the type of the current value.
void	leave(java.lang.Object object) Apply the value as leaving aggregation (leaving window).

Methods inherited from class java.lang.Object

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

Field Detail

mean

protected double mean

qn

protected double qn

numDataPoints

protected long numDataPoints

Constructor Detail

AggregatorStddev

public AggregatorStddev()

Method Detail

clear

public void clear()

Description copied from interface: AggregationMethod

Clear out the collection.

Specified by:

clear in interface AggregationMethod

enter

public void enter(java.lang.Object object)

Description copied from interface: AggregationMethod

Apply the value as entering aggregation (entering window).

The value can be null since 'null' values may be counted as unique separate values.

Specified by:

enter in interface AggregationMethod

Parameters:

object - to add to aggregate

leave

public void leave(java.lang.Object object)

Description copied from interface: AggregationMethod

Apply the value as leaving aggregation (leaving window).

The value can be null since 'null' values may be counted as unique separate values.

Specified by:

leave in interface AggregationMethod

Parameters:

object - to remove from aggregate

getValue

public java.lang.Object getValue()

Description copied from interface: AggregationMethod

Returns the current value held.

Specified by:

getValue in interface AggregationMethod

Returns:

current value

getValueType

public java.lang.Class getValueType()

Description copied from interface: AggregationMethod

Returns the type of the current value.

Specified by:

getValueType in interface AggregationMethod

Returns:

type of values held