org.opentrafficsim.base

Class WeightedMeanAndSum<V extends Number,W extends Number>

java.lang.Object

org.opentrafficsim.base.WeightedMeanAndSum<V,W>

Type Parameters:

V - value type

W - weight type

public class WeightedMeanAndSum<V extends Number,W extends Number>
extends Object

Utility to calculate a weighted mean and/or sum. This can be used as part of a process or loop with information being accumulated in the object. This is even a memory friendly method as this class only stores 2 double values internally.

Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
BSD-style license. See OpenTrafficSim License.

Version:

$Revision$, $LastChangedDate$, by $Author$, initial version 8 okt. 2018

Author:

Alexander Verbraeck, Peter Knoppers, Wouter Schakel

Constructor Summary

Constructors

Constructor and Description
WeightedMeanAndSum() Constructor.

Method Summary

Modifier and Type	Method and Description
<S> WeightedMeanAndSum<V,W>	add(Collection<S> collection, Function<S,V> values, Function<S,W> weights) Adds each value with a weight given by a function.
WeightedMeanAndSum<V,W>	add(Collection<V> collection, Function<V,W> weights) Adds each value with a weight given by a function.
WeightedMeanAndSum<V,W>	add(Iterable<V> values, Iterable<W> weights) Adds a weighted value for each element.
WeightedMeanAndSum<V,W>	add(Map<V,W> map) Adds each weighted value from a map.
WeightedMeanAndSum<V,W>	add(V[] values, W[] weights) Adds a weighted value for each element.
WeightedMeanAndSum<V,W>	add(V value, W weight) Adds a value with weight.
double	getMean() Returns the weighted mean of available data.
double	getSum() Returns the weighted sum of available data.
double	getWeightSum() Returns the sum of the weights.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

WeightedMeanAndSum

public WeightedMeanAndSum()

Constructor.

Method Detail

getMean

public final double getMean()

Returns the weighted mean of available data.

Returns:

double; weighted mean of available data

getSum

public final double getSum()

Returns the weighted sum of available data.

Returns:

double; weighted sum of available data

getWeightSum

public final double getWeightSum()

Returns the sum of the weights.

Returns:

double; sum of the weights

add

public final WeightedMeanAndSum<V,W> add(V value,
                                         W weight)

Adds a value with weight.

Parameters:

value - V; value

weight - W; weight

Returns:

this WeightedMeanAndSum for method chaining

add

public final WeightedMeanAndSum<V,W> add(Iterable<V> values,
                                         Iterable<W> weights)

Adds a weighted value for each element. Note that iteration order is pivotal in correct operations. This method should not be used with instances of HashMap or HashSet.

Parameters:

values - Iterable<V>; values

weights - Iterable<W>; weights

Returns:

this WeightedMeanAndSum<V, W> for method chaining

Throws:

IllegalArgumentException - if the number of values and weights are unequal

add

public final WeightedMeanAndSum<V,W> add(V[] values,
                                         W[] weights)

Adds a weighted value for each element.

Parameters:

values - V[]; values

weights - W[]; weights

Returns:

this WeightedMeanAndSum<V, W> for method chaining

add

public final WeightedMeanAndSum<V,W> add(Map<V,W> map)

Adds each weighted value from a map.

Parameters:

map - Map<V, W>; map

Returns:

this WeightedMeanAndSum<V, W> for method chaining

add

public final WeightedMeanAndSum<V,W> add(Collection<V> collection,
                                         Function<V,W> weights)

Adds each value with a weight given by a function.

Parameters:

collection - Collection<V>; values

weights - Function<V, W>; weights

Returns:

this WeightedMeanAndSum<V, W> for method chaining

add

public final <S> WeightedMeanAndSum<V,W> add(Collection<S> collection,
                                             Function<S,V> values,
                                             Function<S,W> weights)

Adds each value with a weight given by a function.

Type Parameters:

S - type of source object

Parameters:

collection - Collection<S>; collection of source objects

values - Function<S, V>; values

weights - Function<S, W>; weights

Returns:

this WeightedMeanAndSum<V, W> for method chaining