org.apache.commons.math.analysis
Interface DifferentiableMultivariateRealFunction

All Superinterfaces:

MultivariateRealFunction

public interface DifferentiableMultivariateRealFunction
extends MultivariateRealFunction

Extension of MultivariateRealFunction representing a differentiable multivariate real function.

Since:

2.0

Version:

$Revision: 811685 $ $Date: 2009-09-05 19:36:48 +0200 (sam. 05 sept. 2009) $

Method Summary

MultivariateVectorialFunction	gradient() Returns the gradient function.
MultivariateRealFunction	partialDerivative(int k) Returns the partial derivative of the function with respect to a point coordinate.

Methods inherited from interface org.apache.commons.math.analysis.MultivariateRealFunction

value

Method Detail

partialDerivative

MultivariateRealFunction partialDerivative(int k)

Returns the partial derivative of the function with respect to a point coordinate.

The partial derivative is defined with respect to point coordinate x_k. If the partial derivatives with respect to all coordinates are needed, it may be more efficient to use the gradient() method which will compute them all at once.

Parameters:

k - index of the coordinate with respect to which the partial derivative is computed

Returns:

the partial derivative function with respect to k^th point coordinate

gradient

MultivariateVectorialFunction gradient()

Returns the gradient function.

If only one partial derivative with respect to a specific coordinate is needed, it may be more efficient to use the partialDerivative(int) method which will compute only the specified component.

Returns:

the gradient function