fr.cnes.sirius.patrius.math.analysis.function

Class Sigmoid

java.lang.Object

fr.cnes.sirius.patrius.math.analysis.function.Sigmoid

All Implemented Interfaces:

UnivariateDifferentiableFunction, UnivariateFunction, Serializable

public class Sigmoid
extends Object
implements UnivariateDifferentiableFunction

Sigmoid function. It is the inverse of the logit function. A more flexible version, the generalised logistic, is implemented by the Logistic class.

Since:

3.0

Version:

$Id: Sigmoid.java 18108 2017-10-04 06:45:27Z bignon $

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Sigmoid.Parametric Parametric function where the input array contains the parameters of the logit function, ordered as follows: Lower asymptote Higher asymptote

Constructor Summary

Constructors

Constructor and Description
Sigmoid() Usual sigmoid function, where the lower asymptote is 0 and the higher asymptote is 1.
Sigmoid(double loIn, double hiIn) Sigmoid function.

Method Summary

Modifier and Type	Method and Description
DerivativeStructure	value(DerivativeStructure t) Simple mathematical function.
double	value(double x) Compute the value of the function.

Methods inherited from class java.lang.Object

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

Constructor Detail

Sigmoid

public Sigmoid()

Usual sigmoid function, where the lower asymptote is 0 and the higher asymptote is 1.

Sigmoid

public Sigmoid(double loIn,
               double hiIn)

Sigmoid function.

Parameters:

loIn - Lower asymptote.

hiIn - Higher asymptote.

Method Detail

value

public double value(double x)

Compute the value of the function.

Specified by:

value in interface UnivariateFunction

Parameters:

x - Point at which the function value should be computed.

Returns:

the value of the function.

value

public DerivativeStructure value(DerivativeStructure t)

Simple mathematical function.

UnivariateDifferentiableFunction classes compute both the value and the first derivative of the function.

Specified by:

value in interface UnivariateDifferentiableFunction

Parameters:

t - function input value

Returns:

function result

Since:

3.1