Class Sum
- java.lang.Object
-
- org.apache.commons.math.stat.descriptive.AbstractUnivariateStatistic
-
- org.apache.commons.math.stat.descriptive.AbstractStorelessUnivariateStatistic
-
- org.apache.commons.math.stat.descriptive.summary.Sum
-
- All Implemented Interfaces:
java.io.Serializable
,StorelessUnivariateStatistic
,UnivariateStatistic
public class Sum extends AbstractStorelessUnivariateStatistic implements java.io.Serializable
Returns the sum of the available values.If there are no values in the dataset, or any of the values are
NaN
, thenNaN
is returned.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()
orclear()
method, it must be synchronized externally.- See Also:
- Serialized Form
-
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description void
clear()
Clears the internal state of the StatisticSum
copy()
Returns a copy of the statistic with the same internal state.static void
copy(Sum source, Sum dest)
Copies source to dest.double
evaluate(double[] values, double[] weights)
The weighted sum of the entries in the the input array.double
evaluate(double[] values, double[] weights, int begin, int length)
The weighted sum of the entries in the specified portion of the input array, orDouble.NaN
if the designated subarray is empty.double
evaluate(double[] values, int begin, int length)
The sum of the entries in the specified portion of the input array, orDouble.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.-
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
evaluate, getData, setData, setData
-
-
-
-
Constructor Detail
-
Sum
public Sum()
Create a Sum instance
-
Sum
public Sum(Sum original)
Copy constructor, creates a newSum
identical to theoriginal
- Parameters:
original
- theSum
instance to copy
-
-
Method Detail
-
increment
public void increment(double d)
Updates the internal state of the statistic to reflect the addition of the new value.- Specified by:
increment
in interfaceStorelessUnivariateStatistic
- Specified by:
increment
in classAbstractStorelessUnivariateStatistic
- Parameters:
d
- the new value.
-
getResult
public double getResult()
Returns the current value of the Statistic.- Specified by:
getResult
in interfaceStorelessUnivariateStatistic
- Specified by:
getResult
in classAbstractStorelessUnivariateStatistic
- Returns:
- value of the statistic,
Double.NaN
if it has been cleared or just instantiated.
-
getN
public long getN()
Returns the number of values that have been added.- Specified by:
getN
in interfaceStorelessUnivariateStatistic
- Returns:
- the number of values.
-
clear
public void clear()
Clears the internal state of the Statistic- Specified by:
clear
in interfaceStorelessUnivariateStatistic
- Specified by:
clear
in classAbstractStorelessUnivariateStatistic
-
evaluate
public double evaluate(double[] values, int begin, int length)
The sum of the entries in the specified portion of the input array, orDouble.NaN
if the designated subarray is empty.Throws
IllegalArgumentException
if the array is null.- Specified by:
evaluate
in interfaceUnivariateStatistic
- Overrides:
evaluate
in classAbstractStorelessUnivariateStatistic
- Parameters:
values
- the input arraybegin
- index of the first array element to includelength
- the number of elements to include- Returns:
- the sum of the values or Double.NaN if length = 0
- Throws:
java.lang.IllegalArgumentException
- if the array is null or the array index parameters are not valid- See Also:
UnivariateStatistic.evaluate(double[], int, int)
-
evaluate
public double evaluate(double[] values, double[] weights, int begin, int length)
The weighted sum of the entries in the specified portion of the input array, orDouble.NaN
if the designated subarray is empty.Throws
IllegalArgumentException
if any of the following are true:- the values array is null
- the weights array is null
- the weights array does not have the same length as the values array
- the weights array contains one or more infinite values
- the weights array contains one or more NaN values
- the weights array contains negative values
- the start and length arguments do not determine a valid array
Uses the formula,
weighted sum = Σ(values[i] * weights[i])
- Parameters:
values
- the input arrayweights
- the weights arraybegin
- index of the first array element to includelength
- the number of elements to include- Returns:
- the sum of the values or Double.NaN if length = 0
- Throws:
java.lang.IllegalArgumentException
- if the parameters are not valid- Since:
- 2.1
-
evaluate
public double evaluate(double[] values, double[] weights)
The weighted sum of the entries in the the input array.Throws
IllegalArgumentException
if any of the following are true:- the values array is null
- the weights array is null
- the weights array does not have the same length as the values array
- the weights array contains one or more infinite values
- the weights array contains one or more NaN values
- the weights array contains negative values
Uses the formula,
weighted sum = Σ(values[i] * weights[i])
- Parameters:
values
- the input arrayweights
- the weights array- Returns:
- the sum of the values or Double.NaN if length = 0
- Throws:
java.lang.IllegalArgumentException
- if the parameters are not valid- Since:
- 2.1
-
copy
public Sum copy()
Returns a copy of the statistic with the same internal state.- Specified by:
copy
in interfaceStorelessUnivariateStatistic
- Specified by:
copy
in interfaceUnivariateStatistic
- Specified by:
copy
in classAbstractStorelessUnivariateStatistic
- Returns:
- a copy of the statistic
-
-