FunctionUtils (Apache Commons Math 3.4 API)

java.lang.Object
- org.apache.commons.math3.analysis.FunctionUtils

```
public class FunctionUtils
extends Object
```
Utilities for manipulating function objects.

Since:

3.0

Method Summary

Methods
Modifier and Type	Method and Description
`static DifferentiableUnivariateFunction`	`add(DifferentiableUnivariateFunction... f)` Deprecated. as of 3.1 replaced by `add(UnivariateDifferentiableFunction...)`
`static UnivariateDifferentiableFunction`	`add(UnivariateDifferentiableFunction... f)` Adds functions.
`static UnivariateFunction`	`add(UnivariateFunction... f)` Adds functions.
`static MultivariateFunction`	`collector(BivariateFunction combiner, double initialValue)` Returns a MultivariateFunction h(x[]) defined by `h(x[]) = combiner(...combiner(combiner(initialValue,x[0]),x[1])...)`
`static MultivariateFunction`	`collector(BivariateFunction combiner, UnivariateFunction f, double initialValue)` Returns a MultivariateFunction h(x[]) defined by `h(x[]) = combiner(...combiner(combiner(initialValue,f(x[0])),f(x[1]))...)`
`static UnivariateFunction`	`combine(BivariateFunction combiner, UnivariateFunction f, UnivariateFunction g)` Returns the univariate function `h(x) = combiner(f(x), g(x))`.
`static DifferentiableUnivariateFunction`	`compose(DifferentiableUnivariateFunction... f)` Deprecated. as of 3.1 replaced by `compose(UnivariateDifferentiableFunction...)`
`static UnivariateDifferentiableFunction`	`compose(UnivariateDifferentiableFunction... f)` Composes functions.
`static UnivariateFunction`	`compose(UnivariateFunction... f)` Composes functions.
`static UnivariateFunction`	`fix1stArgument(BivariateFunction f, double fixed)` Creates a unary function by fixing the first argument of a binary function.
`static UnivariateFunction`	`fix2ndArgument(BivariateFunction f, double fixed)` Creates a unary function by fixing the second argument of a binary function.
`static DifferentiableUnivariateFunction`	`multiply(DifferentiableUnivariateFunction... f)` Deprecated. as of 3.1 replaced by `multiply(UnivariateDifferentiableFunction...)`
`static UnivariateDifferentiableFunction`	`multiply(UnivariateDifferentiableFunction... f)` Multiplies functions.
`static UnivariateFunction`	`multiply(UnivariateFunction... f)` Multiplies functions.
`static double[]`	`sample(UnivariateFunction f, double min, double max, int n)` Samples the specified univariate real function on the specified interval.
`static DifferentiableMultivariateFunction`	`toDifferentiableMultivariateFunction(MultivariateDifferentiableFunction f)` Deprecated. this conversion method is temporary in version 3.1, as the `DifferentiableMultivariateFunction` interface itself is deprecated
`static DifferentiableMultivariateVectorFunction`	`toDifferentiableMultivariateVectorFunction(MultivariateDifferentiableVectorFunction f)` Deprecated. this conversion method is temporary in version 3.1, as the `DifferentiableMultivariateVectorFunction` interface itself is deprecated
`static DifferentiableUnivariateFunction`	`toDifferentiableUnivariateFunction(UnivariateDifferentiableFunction f)` Deprecated. this conversion method is temporary in version 3.1, as the `DifferentiableUnivariateFunction` interface itself is deprecated
`static MultivariateDifferentiableFunction`	`toMultivariateDifferentiableFunction(DifferentiableMultivariateFunction f)` Deprecated. this conversion method is temporary in version 3.1, as the `DifferentiableMultivariateFunction` interface itself is deprecated
`static MultivariateDifferentiableVectorFunction`	`toMultivariateDifferentiableVectorFunction(DifferentiableMultivariateVectorFunction f)` Deprecated. this conversion method is temporary in version 3.1, as the `DifferentiableMultivariateFunction` interface itself is deprecated
`static UnivariateDifferentiableFunction`	`toUnivariateDifferential(DifferentiableUnivariateFunction f)` Deprecated. this conversion method is temporary in version 3.1, as the `DifferentiableUnivariateFunction` interface itself is deprecated

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

- Method Detail
  - compose
```
public static UnivariateFunction compose(UnivariateFunction... f)
```
    Composes functions.
    The functions in the argument list are composed sequentially, in the given order. For example, compose(f1,f2,f3) acts like f1(f2(f3(x))).
    
    Parameters:
    f - List of functions.
    
    Returns:
    the composite function.
  - compose
```
public static UnivariateDifferentiableFunction compose(UnivariateDifferentiableFunction... f)
```
    Composes functions.
    The functions in the argument list are composed sequentially, in the given order. For example, compose(f1,f2,f3) acts like f1(f2(f3(x))).
    
    Parameters:
    f - List of functions.
    
    Returns:
    the composite function.
    Since:
    
    3.1
  - compose
```
@Deprecated
public static DifferentiableUnivariateFunction compose(DifferentiableUnivariateFunction... f)
```
    Deprecated. as of 3.1 replaced by compose(UnivariateDifferentiableFunction...)
    
    Composes functions.
    The functions in the argument list are composed sequentially, in the given order. For example, compose(f1,f2,f3) acts like f1(f2(f3(x))).
    
    Parameters:
    f - List of functions.
    
    Returns:
    the composite function.
  - add
```
public static UnivariateFunction add(UnivariateFunction... f)
```
    Adds functions.
    
    Parameters:
    f - List of functions.
    
    Returns:
    a function that computes the sum of the functions.
  - add
```
public static UnivariateDifferentiableFunction add(UnivariateDifferentiableFunction... f)
```
    Adds functions.
    
    Parameters:
    f - List of functions.
    
    Returns:
    a function that computes the sum of the functions.
    Since:
    
    3.1
  - add
```
@Deprecated
public static DifferentiableUnivariateFunction add(DifferentiableUnivariateFunction... f)
```
    Deprecated. as of 3.1 replaced by add(UnivariateDifferentiableFunction...)
    
    Adds functions.
    
    Parameters:
    f - List of functions.
    
    Returns:
    a function that computes the sum of the functions.
  - multiply
```
public static UnivariateFunction multiply(UnivariateFunction... f)
```
    Multiplies functions.
    
    Parameters:
    f - List of functions.
    
    Returns:
    a function that computes the product of the functions.
  - multiply
```
public static UnivariateDifferentiableFunction multiply(UnivariateDifferentiableFunction... f)
```
    Multiplies functions.
    
    Parameters:
    f - List of functions.
    
    Returns:
    a function that computes the product of the functions.
    Since:
    
    3.1
  - multiply
```
@Deprecated
public static DifferentiableUnivariateFunction multiply(DifferentiableUnivariateFunction... f)
```
    Deprecated. as of 3.1 replaced by multiply(UnivariateDifferentiableFunction...)
    
    Multiplies functions.
    
    Parameters:
    f - List of functions.
    
    Returns:
    a function that computes the product of the functions.
  - combine
```
public static UnivariateFunction combine(BivariateFunction combiner,
                         UnivariateFunction f,
                         UnivariateFunction g)
```
    Returns the univariate function
    h(x) = combiner(f(x), g(x)).
    
    Parameters:
    combiner - Combiner function.
    f - Function.
    g - Function.
    
    Returns:
    the composite function.
  - collector
```
public static MultivariateFunction collector(BivariateFunction combiner,
                             UnivariateFunction f,
                             double initialValue)
```
    Returns a MultivariateFunction h(x[]) defined by
```
 
 h(x[]) = combiner(...combiner(combiner(initialValue,f(x[0])),f(x[1]))...),f(x[x.length-1]))
 
```
    Parameters:
    combiner - Combiner function.
    f - Function.
    initialValue - Initial value.
    
    Returns:
    a collector function.
  - collector
```
public static MultivariateFunction collector(BivariateFunction combiner,
                             double initialValue)
```
    Returns a MultivariateFunction h(x[]) defined by
```
 
 h(x[]) = combiner(...combiner(combiner(initialValue,x[0]),x[1])...),x[x.length-1])
 
```
    Parameters:
    combiner - Combiner function.
    initialValue - Initial value.
    
    Returns:
    a collector function.
  - fix1stArgument
```
public static UnivariateFunction fix1stArgument(BivariateFunction f,
                                double fixed)
```
    Creates a unary function by fixing the first argument of a binary function.
    
    Parameters:
    f - Binary function.
    fixed - Value to which the first argument of f is set.
    
    Returns:
    the unary function h(x) = f(fixed, x)
  - fix2ndArgument
```
public static UnivariateFunction fix2ndArgument(BivariateFunction f,
                                double fixed)
```
    Creates a unary function by fixing the second argument of a binary function.
    
    Parameters:
    f - Binary function.
    fixed - Value to which the second argument of f is set.
    
    Returns:
    the unary function h(x) = f(x, fixed)
  - sample
```
public static double[] sample(UnivariateFunction f,
              double min,
              double max,
              int n)
                       throws NumberIsTooLargeException,
                              NotStrictlyPositiveException
```
    Samples the specified univariate real function on the specified interval.
    The interval is divided equally into n sections and sample points are taken from min to max - (max - min) / n; therefore f is not sampled at the upper bound max.
    
    Parameters:
    f - Function to be sampled
    min - Lower bound of the interval (included).
    max - Upper bound of the interval (excluded).
    n - Number of sample points.
    
    Returns:
    the array of samples.
    
    Throws:
    
    NumberIsTooLargeException - if the lower bound min is greater than, or equal to the upper bound max.
    
    NotStrictlyPositiveException - if the number of sample points n is negative.
  - toDifferentiableUnivariateFunction
```
@Deprecated
public static DifferentiableUnivariateFunction toDifferentiableUnivariateFunction(UnivariateDifferentiableFunction f)
```
    Deprecated. this conversion method is temporary in version 3.1, as the DifferentiableUnivariateFunction interface itself is deprecated
    
    Convert a UnivariateDifferentiableFunction into a DifferentiableUnivariateFunction.
    
    Parameters:
    f - function to convert
    
    Returns:
    converted function
  - toUnivariateDifferential
```
@Deprecated
public static UnivariateDifferentiableFunction toUnivariateDifferential(DifferentiableUnivariateFunction f)
```
    Deprecated. this conversion method is temporary in version 3.1, as the DifferentiableUnivariateFunction interface itself is deprecated
    
    Convert a DifferentiableUnivariateFunction into a UnivariateDifferentiableFunction.
    Note that the converted function is able to handle DerivativeStructure up to order one. If the function is called with higher order, a NumberIsTooLargeException will be thrown.
    
    Parameters:
    f - function to convert
    
    Returns:
    converted function
  - toDifferentiableMultivariateFunction
```
@Deprecated
public static DifferentiableMultivariateFunction toDifferentiableMultivariateFunction(MultivariateDifferentiableFunction f)
```
    Deprecated. this conversion method is temporary in version 3.1, as the DifferentiableMultivariateFunction interface itself is deprecated
    
    Convert a MultivariateDifferentiableFunction into a DifferentiableMultivariateFunction.
    
    Parameters:
    f - function to convert
    
    Returns:
    converted function
  - toMultivariateDifferentiableFunction
```
@Deprecated
public static MultivariateDifferentiableFunction toMultivariateDifferentiableFunction(DifferentiableMultivariateFunction f)
```
    Deprecated. this conversion method is temporary in version 3.1, as the DifferentiableMultivariateFunction interface itself is deprecated
    
    Convert a DifferentiableMultivariateFunction into a MultivariateDifferentiableFunction.
    Note that the converted function is able to handle DerivativeStructure elements that all have the same number of free parameters and order, and with order at most 1. If the function is called with inconsistent numbers of free parameters or higher order, a DimensionMismatchException or a NumberIsTooLargeException will be thrown.
    
    Parameters:
    f - function to convert
    
    Returns:
    converted function
  - toDifferentiableMultivariateVectorFunction
```
@Deprecated
public static DifferentiableMultivariateVectorFunction toDifferentiableMultivariateVectorFunction(MultivariateDifferentiableVectorFunction f)
```
    Deprecated. this conversion method is temporary in version 3.1, as the DifferentiableMultivariateVectorFunction interface itself is deprecated
    
    Convert a MultivariateDifferentiableVectorFunction into a DifferentiableMultivariateVectorFunction.
    
    Parameters:
    f - function to convert
    
    Returns:
    converted function
  - toMultivariateDifferentiableVectorFunction
```
@Deprecated
public static MultivariateDifferentiableVectorFunction toMultivariateDifferentiableVectorFunction(DifferentiableMultivariateVectorFunction f)
```
    Deprecated. this conversion method is temporary in version 3.1, as the DifferentiableMultivariateFunction interface itself is deprecated
    
    Convert a DifferentiableMultivariateVectorFunction into a MultivariateDifferentiableVectorFunction.
    Note that the converted function is able to handle DerivativeStructure elements that all have the same number of free parameters and order, and with order at most 1. If the function is called with inconsistent numbers of free parameters or higher order, a DimensionMismatchException or a NumberIsTooLargeException will be thrown.
    
    Parameters:
    f - function to convert
    
    Returns:
    converted function

Class FunctionUtils

Method Summary

Methods inherited from class java.lang.Object

Method Detail

compose

compose

compose

add

add

add

multiply

multiply

multiply

combine

collector

collector

fix1stArgument

fix2ndArgument

sample

toDifferentiableUnivariateFunction

toUnivariateDifferential

toDifferentiableMultivariateFunction

toMultivariateDifferentiableFunction

toDifferentiableMultivariateVectorFunction

toMultivariateDifferentiableVectorFunction