jsat.math

Interface Function

All Superinterfaces:

java.io.Serializable

All Known Subinterfaces:

IndexFunction, WordWeighting

All Known Implementing Classes:

BinaryWordPresent, LinearBatch.LossFunction, LinearBatch.LossMCFunction, OkapiBM25, RosenbrockFunction, TfIdf, WordCount

public interface Function
extends java.io.Serializable

This functional interface defines a function over a vector input and returns a scalar output.

Method Summary

Modifier and Type	Method and Description
default double	f(double... x) Evaluates the given function for the specified input vector.
default double	f(Vec x) Evaluates the given function for the specified input vector.
double	f(Vec x, boolean parallel) Evaluates the given function for the specified input vector.
static FunctionVec	forwardDifference(Function f) Returns a new function that approximates the derivative of the given one via numerical forward difference approximation.

Method Detail

f

default double f(double... x)

Evaluates the given function for the specified input vector.

Parameters:

x - the input to the function

Returns:

the scalar output of this function

f

default double f(Vec x)

Evaluates the given function for the specified input vector.

Parameters:

x - the input to the function

Returns:

the scalar output of this function

f

double f(Vec x,
         boolean parallel)

Evaluates the given function for the specified input vector.

Parameters:

x - the input to the function

parallel - true if the function should be evaluated with multiple threads, or false to use a single thread.

Returns:

the scalar output of this function

forwardDifference

static FunctionVec forwardDifference(Function f)

Returns a new function that approximates the derivative of the given one via numerical forward difference approximation.

Parameters:

f - the function to approximate the derivative of

Returns:

a function that will return an estimate of the derivative