com.numericalmethod.suanshu.analysis.function.rn2r1

Class Projection

java.lang.Object

com.numericalmethod.suanshu.analysis.function.rn2r1.Projection

All Implemented Interfaces:

Function<Vector,java.lang.Double>, RealScalarFunction, java.io.Serializable

public class Projection
extends java.lang.Object
implements RealScalarFunction

Projection creates a real-valued function RealScalarFunction from a vector-valued function RealVectorFunction by taking only one of its coordinate components in the vector output. For example, suppose we have a \(R^n \rightarrow R^m\) function, \(f_1 = [y_1, y_2, y_3]'\). We construct a \(R^n \rightarrow R\) function by taking its second coordinate. That is, \(f_2 = y_2\).

See Also:

Serialized Form

Nested Class Summary

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

Function.EvaluationException

Constructor Summary

Constructors

Constructor and Description
Projection(RealVectorFunction f, int dimension) Construct a \(R^n \rightarrow R\) projection from a \(R^n \rightarrow R^m\) function f.

Method Summary

Modifier and Type	Method and Description
int	dimensionOfDomain() Get the number of variables the function has.
int	dimensionOfRange() Get the dimension of the range space of the function.
java.lang.Double	evaluate(Vector x) Evaluate the function f at x, where x is from the domain.

Methods inherited from class java.lang.Object

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

Constructor Detail

Projection

public Projection(RealVectorFunction f,
                  int dimension)

Construct a \(R^n \rightarrow R\) projection from a \(R^n \rightarrow R^m\) function f.

Parameters:

f - a vector-valued function

dimension - the dimension/coordinate of the f value to output

Method Detail

evaluate

public java.lang.Double evaluate(Vector x)

Description copied from interface: Function

Evaluate the function f at x, where x is from the domain.

Specified by:

evaluate in interface Function<Vector,java.lang.Double>

Parameters:

x - x

Returns:

f(x)

dimensionOfDomain

public int dimensionOfDomain()

Description copied from interface: Function

Get the number of variables the function has. For example, for a univariate function, the domain dimension is 1; for a bivariate function, the domain dimension is 2.

Specified by:

dimensionOfDomain in interface Function<Vector,java.lang.Double>

Returns:

the number of variables

dimensionOfRange

public int dimensionOfRange()

Description copied from interface: Function

Get the dimension of the range space of the function. For example, for a Rⁿ->R^m function, the dimension of the range is m.

Specified by:

dimensionOfRange in interface Function<Vector,java.lang.Double>

Returns:

the dimension of the range