public class StdDevSAggregator<V extends java.lang.Number> extends VarSAggregator<V>
This class implements the SQL Standard STDDEV_SAMP() aggregator, computing a sample's standard deviation. It relies on VarSAggregator to compute the sample's variance and then applies the textbook definition of standard deviation:
√var_samp()
VarPAggregator.Sums
Modifier and Type | Field and Description |
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private static long |
serialVersionUID |
count, sums
Constructor and Description |
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StdDevSAggregator() |
Modifier and Type | Method and Description |
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java.lang.Double |
terminate()
Return the result scalar value
|
computeVar
accumulate, init, merge, readExternal, writeExternal
private static final long serialVersionUID
public java.lang.Double terminate()
Aggregator
terminate
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>
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