java.io.Externalizable, java.io.Serializable, Aggregator<V,java.lang.Double,VarPAggregator<V>>public class StdDevPAggregator<V extends java.lang.Number> extends VarPAggregator<V>
This class implements the SQL Standard STDDEV_POP() aggregator, computing a population's standard deviation. It relies on VarPAggregator to compute the population variance and then applies the textbook definition of standard deviation:
√var_pop()
VarPAggregator.Sums| Modifier and Type | Field | Description |
|---|---|---|
private static long |
serialVersionUID |
count, sums| Constructor | Description |
|---|---|
StdDevPAggregator() |
| Modifier and Type | Method | Description |
|---|---|---|
java.lang.Double |
terminate() |
Return the result scalar value
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitaccumulate, computeVar, init, merge, readExternal, writeExternalprivate static final long serialVersionUID
public java.lang.Double terminate()
Aggregatorterminate in interface Aggregator<V extends java.lang.Number,java.lang.Double,VarPAggregator<V extends java.lang.Number>>terminate in class VarPAggregator<V extends java.lang.Number>Apache Derby V10.14 Internals - Copyright © 2004,2018 The Apache Software Foundation. All Rights Reserved.