|
|||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectorg.apache.commons.math.stat.descriptive.AbstractUnivariateStatistic
org.apache.commons.math.stat.descriptive.AbstractStorelessUnivariateStatistic
org.apache.commons.math.stat.descriptive.moment.GeometricMean
Returns the geometric mean of the available values.
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 Summary | |
GeometricMean()
Create a GeometricMean instance |
Method Summary | |
void |
clear()
Clears the internal state of the Statistic |
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. |
Methods inherited from class org.apache.commons.math.stat.descriptive.AbstractStorelessUnivariateStatistic |
equals, evaluate, hashCode, incrementAll, incrementAll |
Methods inherited from class org.apache.commons.math.stat.descriptive.AbstractUnivariateStatistic |
test |
Methods inherited from class java.lang.Object |
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait |
Constructor Detail |
public GeometricMean()
Method Detail |
public void increment(double d)
StorelessUnivariateStatistic
increment
in interface StorelessUnivariateStatistic
increment
in class AbstractStorelessUnivariateStatistic
StorelessUnivariateStatistic.increment(double)
public double getResult()
StorelessUnivariateStatistic
getResult
in interface StorelessUnivariateStatistic
getResult
in class AbstractStorelessUnivariateStatistic
StorelessUnivariateStatistic.getResult()
public void clear()
StorelessUnivariateStatistic
clear
in interface StorelessUnivariateStatistic
clear
in class AbstractStorelessUnivariateStatistic
StorelessUnivariateStatistic.clear()
public double evaluate(double[] values, int begin, int length)
See GeometricMean
for details on the computing algorithm.
Throws IllegalArgumentException
if the array is null.
evaluate
in interface UnivariateStatistic
evaluate
in class AbstractStorelessUnivariateStatistic
values
- input array containing the valuesbegin
- first array element to includelength
- the number of elements to include
IllegalArgumentException
- if the input array is null or the array
index parameters are not validUnivariateStatistic.evaluate(double[], int, int)
public long getN()
StorelessUnivariateStatistic
StorelessUnivariateStatistic.getN()
|
|||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |