com.numericalmethod.suanshu.analysis.function.rn2r1
Class RealScalarFunctionFixedVariables

java.lang.Object
  com.numericalmethod.suanshu.analysis.function.rn2r1.RealScalarFunctionFixedVariables

All Implemented Interfaces:

Function, RealScalarFunction

public class RealScalarFunctionFixedVariables
extends java.lang.Object
implements RealScalarFunction

This creates a a RealScalarFunction from another RealScalarFunction by fixing the values of a subset of variables.

Nested Class Summary

static class

RealScalarFunctionFixedVariables.Value

Nested classes/interfaces inherited from interface com.numericalmethod.suanshu.analysis.function.Function

Function.EvaluationException

Constructor Summary

RealScalarFunctionFixedVariables(RealScalarFunction f, java.util.Collection<RealScalarFunctionFixedVariables.Value> values)

RealScalarFunctionFixedVariables(RealScalarFunction f, RealScalarFunctionFixedVariables.Value... values)

Method Summary

int	dimension4Domain() Get the number of variables of the function.
int	dimension4Range() Get the dimension of the range space the function.
double	evaluate(double... x) A real function, f, takes a double array double[], {x0, x1, ..., xn} and maps it to a double, f(x0, x1, ..., xn)
boolean	isIntegerIndex(int idx) Check whether a particular index corresponds an integral variable.
static double[]	pack(double[] reals, java.util.Collection<RealScalarFunctionFixedVariables.Value> integers) Combine the real and integer parts to form a vector input to the original function.
double[]	realPart(double[] z) Given a vector input to the original function, this extracts the real parts (excluding the fixed integer values).

Methods inherited from class java.lang.Object

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

Constructor Detail

RealScalarFunctionFixedVariables

public RealScalarFunctionFixedVariables(RealScalarFunction f,
                                        java.util.Collection<RealScalarFunctionFixedVariables.Value> values)

RealScalarFunctionFixedVariables

public RealScalarFunctionFixedVariables(RealScalarFunction f,
                                        RealScalarFunctionFixedVariables.Value... values)

Method Detail

evaluate

public double evaluate(double... x)

Description copied from interface: RealScalarFunction

A real function, f, takes a double array double[],

{x0, x1, ..., xn}

and maps it to a double,

f(x0, x1, ..., xn)

Specified by:

evaluate in interface RealScalarFunction

Parameters:

x - {x} = {x0, x1, ... xn}

Returns:

f({x}) as output

dimension4Domain

public int dimension4Domain()

Description copied from interface: Function

Get the number of variables of the function.

For example, for a univariate function, the domain dimension is 1. For a bivariate function, the domain dimension is 2.

Specified by:

dimension4Domain in interface Function

Returns:

the number of variables

dimension4Range

public int dimension4Range()

Description copied from interface: Function

Get the dimension of the range space the function.

For example, for a Rn->Rm function, the dimension of the range is m.

Specified by:

dimension4Range in interface Function

Returns:

the dimension of the range

isIntegerIndex

public boolean isIntegerIndex(int idx)

Check whether a particular index corresponds an integral variable.

Parameters:

idx - an index

Returns:

true iff x[idx] is an integer

realPart

public double[] realPart(double[] z)

Given a vector input to the original function, this extracts the real parts (excluding the fixed integer values).

Parameters:

z - an input to the original function

Returns:

the real sub-part of z

pack

public static double[] pack(double[] reals,
                            java.util.Collection<RealScalarFunctionFixedVariables.Value> integers)

Combine the real and integer parts to form a vector input to the original function.

Parameters:

reals - the real values to the non-integral variables

integers - the integer values to the integral variables

Returns:

a vector input to the original function