public class SumOfLogs extends AbstractStorelessUnivariateStatistic implements Serializable
Uses FastMath.log(double)
to compute the logs.
Therefore,
NaN.
Double.POSITIVE_INFINITY
, but at least one value is 0, the
result is Double.NEGATIVE_INFINITY.
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 |
---|
SumOfLogs()
Create a SumOfLogs instance
|
SumOfLogs(SumOfLogs original)
Copy constructor, creates a new
SumOfLogs identical
to the original |
Modifier and Type | Method and Description |
---|---|
void |
clear()
Clears the internal state of the Statistic
|
SumOfLogs |
copy()
Returns a copy of the statistic with the same internal state.
|
static void |
copy(SumOfLogs source,
SumOfLogs dest)
Copies source to dest.
|
double |
evaluate(double[] values,
int begin,
int length)
Returns the sum of the natural logs of the entries in the specified portion of
the input array, or
Double.NaN if the designated subarray
is empty. |
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, evaluate, hashCode, incrementAll, incrementAll
evaluate, getData, getDataRef, setData, setData, test, test, test, test
public SumOfLogs()
public SumOfLogs(SumOfLogs original) throws NullArgumentException
SumOfLogs
identical
to the original
original
- the SumOfLogs
instance to copyNullArgumentException
- if original is nullpublic void increment(double d)
increment
in interface StorelessUnivariateStatistic
increment
in class AbstractStorelessUnivariateStatistic
d
- the new value.public double getResult()
getResult
in interface StorelessUnivariateStatistic
getResult
in class AbstractStorelessUnivariateStatistic
Double.NaN
if it
has been cleared or just instantiated.public long getN()
getN
in interface StorelessUnivariateStatistic
public void clear()
clear
in interface StorelessUnivariateStatistic
clear
in class AbstractStorelessUnivariateStatistic
public double evaluate(double[] values, int begin, int length) throws MathIllegalArgumentException
Double.NaN
if the designated subarray
is empty.
Throws MathIllegalArgumentException
if the array is null.
See SumOfLogs
.
evaluate
in interface UnivariateStatistic
evaluate
in interface MathArrays.Function
evaluate
in class AbstractStorelessUnivariateStatistic
values
- the input arraybegin
- index of the first array element to includelength
- the number of elements to includeMathIllegalArgumentException
- if the array is null or the array index
parameters are not validUnivariateStatistic.evaluate(double[], int, int)
public SumOfLogs copy()
copy
in interface StorelessUnivariateStatistic
copy
in interface UnivariateStatistic
copy
in class AbstractStorelessUnivariateStatistic
public static void copy(SumOfLogs source, SumOfLogs dest) throws NullArgumentException
Neither source nor dest can be null.
source
- SumOfLogs to copydest
- SumOfLogs to copy toNullArgumentException
- if either source or dest is nullCopyright © 2003–2016 The Apache Software Foundation. All rights reserved.