public class GeometricMean extends AbstractStorelessUnivariateStatistic implements AggregatableStatistic<GeometricMean>, Serializable
Uses a SumOfLogs instance to compute sum of logs and returns
exp( 1/n (sum of logs) ). Therefore,
NaN.Double.POSITIVE_INFINITY, but at least one value is 0, the
result is 0.Double.POSITIVE_INFINITY and
Double.NEGATIVE_INFINITY are among the values, the result is
NaN.
Note that this implementation is not synchronized. If
multiple threads access an instance of this class concurrently, and at least
one of the threads invokes the increment() or
clear() method, it must be synchronized externally.
| Constructor and Description |
|---|
GeometricMean()
Create a GeometricMean instance.
|
GeometricMean(GeometricMean original)
Copy constructor, creates a new
GeometricMean identical
to the original. |
GeometricMean(SumOfLogs sumOfLogs)
Create a GeometricMean instance using the given SumOfLogs instance.
|
| Modifier and Type | Method and Description |
|---|---|
void |
aggregate(GeometricMean other)
Aggregates the provided instance into this instance.
|
void |
clear()
Clears the internal state of the Statistic
|
GeometricMean |
copy()
Returns a copy of the statistic with the same internal state.
|
double |
evaluate(double[] values,
int begin,
int length)
Returns the geometric mean of the entries in the specified portion
of the input array.
|
long |
getN()
Returns the number of values that have been added.
|
double |
getResult()
Returns the current value of the Statistic.
|
void |
increment(double d)
Updates the internal state of the statistic to reflect the addition of the new value.
|
equals, hashCode, toStringclone, finalize, getClass, notify, notifyAll, wait, wait, waitaggregate, aggregateaccept, incrementAll, incrementAllevaluateandThenpublic GeometricMean()
public GeometricMean(SumOfLogs sumOfLogs)
sumOfLogs - sum of logs instance to use for computation.public GeometricMean(GeometricMean original) throws NullArgumentException
GeometricMean identical
to the original.original - the GeometricMean instance to copyNullArgumentException - if original is nullpublic GeometricMean copy()
copy in interface StorelessUnivariateStatisticcopy in interface UnivariateStatisticcopy in class AbstractStorelessUnivariateStatisticpublic void increment(double d)
increment in interface StorelessUnivariateStatisticincrement in class AbstractStorelessUnivariateStatisticd - the new value.public double getResult()
getResult in interface StorelessUnivariateStatisticgetResult in class AbstractStorelessUnivariateStatisticDouble.NaN if it
has been cleared or just instantiated.public void clear()
clear in interface StorelessUnivariateStatisticclear in class AbstractStorelessUnivariateStatisticpublic void aggregate(GeometricMean other)
This method can be used to combine statistics computed over partitions or subsamples - i.e., the value of this instance after this operation should be the same as if a single statistic would have been applied over the combined dataset.
aggregate in interface AggregatableStatistic<GeometricMean>other - the instance to aggregate into this instancepublic double evaluate(double[] values,
int begin,
int length)
throws MathIllegalArgumentException
See GeometricMean for details on the computing algorithm.
evaluate in interface StorelessUnivariateStatisticevaluate in interface UnivariateStatisticevaluate in interface MathArrays.Functionvalues - input array containing the valuesbegin - first array element to includelength - the number of elements to includeMathIllegalArgumentException - if the input array is null or the array
index parameters are not validUnivariateStatistic.evaluate(double[], int, int)public long getN()
getN in interface StorelessUnivariateStatisticCopyright © 2016–2019 Hipparchus.org. All rights reserved.