CompensatedSum (Flink : Java 1.20.1-cp2 API)

java.lang.Object
- org.apache.flink.api.java.summarize.aggregation.CompensatedSum

All Implemented Interfaces:

Serializable
```
@Internal
public class CompensatedSum
extends Object
implements Serializable
```
Used to calculate sums using the Kahan summation algorithm.
The Kahan summation algorithm (also known as compensated summation) reduces the numerical errors that occur when adding a sequence of finite precision floating point numbers. Numerical errors arise due to truncation and rounding. These errors can lead to numerical instability.

See Also:

Kahan Summation Algorithm, Serialized Form

Field Summary

Fields
Modifier and Type Field Description

static CompensatedSum ZERO

Constructor Summary

Constructors
Constructor Description

CompensatedSum(double value, double delta)
Used to calculate sums using the Kahan summation algorithm.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`CompensatedSum`	`add(double value)`	Increments the Kahan sum by adding a value without a correction term.
`CompensatedSum`	`add(double value, double delta)`	Increments the Kahan sum by adding a value and a correction term.
`CompensatedSum`	`add(CompensatedSum other)`	Increments the Kahan sum by adding two sums, and updating the correction term for reducing numeric errors.
`double`	`delta()`	The correction term.
`double`	`value()`	The value of the sum.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ZERO
```
public static final CompensatedSum ZERO
```
- Constructor Detail
  - CompensatedSum
```
public CompensatedSum(double value,
                      double delta)
```
    Used to calculate sums using the Kahan summation algorithm.
    
    Parameters:
    
    value - the sum
    
    delta - correction term
- Method Detail
  - value
```
public double value()
```
    The value of the sum.
  - delta
```
public double delta()
```
    The correction term.
  - add
```
public CompensatedSum add(double value,
                          double delta)
```
    Increments the Kahan sum by adding a value and a correction term.
  - add
```
public CompensatedSum add(double value)
```
    Increments the Kahan sum by adding a value without a correction term.
  - add
```
public CompensatedSum add(CompensatedSum other)
```
    Increments the Kahan sum by adding two sums, and updating the correction term for reducing numeric errors.