Package org.apache.commons.math.optimization
This package provides common interfaces for the optimization algorithms
provided in sub-packages. The main interfaces defines optimizers and convergence
checkers. The functions that are optimized by the algorithms provided by this
package and its sub-packages are a subset of the one defined in the analysis
package, namely the real and vector valued functions. These functions are called
objective function here. When the goal is to minimize, the functions are often called
cost function, this name is not used in this package.
Optimizers are the algorithms that will either minimize or maximize, the objective function by changing its input variables set until an optimal set is found. There are only four interfaces defining the common behavior of optimizers, one for each supported type of objective function:
UnivariateRealOptimizer
forunivariate real functions
MultivariateRealOptimizer
formultivariate real functions
DifferentiableMultivariateRealOptimizer
fordifferentiable multivariate real functions
DifferentiableMultivariateVectorialOptimizer
fordifferentiable multivariate vectorial functions
Despite there are only four types of supported optimizers, it is possible to optimize a
transform a non-differentiable multivariate vectorial function
by converting it to a non-differentiable multivariate
real function
thanks to the LeastSquaresConverter
helper class.
The transformed function can be optimized using any implementation of the MultivariateRealOptimizer
interface.
For each of the four types of supported optimizers, there is a special implementation which wraps a classical optimizer in order to add it a multi-start feature. This feature call the underlying optimizer several times in sequence with different starting points and returns the best optimum found or all optima if desired. This is a classical way to prevent being trapped into a local extremum when looking for a global one.
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ClassDescriptionThis interface represents an optimization algorithm for
scalar differentiable objective functions
.This interface represents an optimization algorithm forvectorial differentiable objective functions
.Goal type for an optimization problem.This class convertsvectorial objective functions
toscalar objective functions
when the goal is to minimize them.Special implementation of theDifferentiableMultivariateRealOptimizer
interface adding multi-start features to an existing optimizer.Special implementation of theDifferentiableMultivariateVectorialOptimizer
interface adding multi-start features to an existing optimizer.Special implementation of theMultivariateRealOptimizer
interface adding multi-start features to an existing optimizer.Special implementation of theUnivariateRealOptimizer
interface adding multi-start features to an existing optimizer.This interface represents an optimization algorithm forscalar objective functions
.Deprecated.in 2.2 (to be removed in 3.0).This interface specifies how to check if anoptimization algorithm
has converged.This class holds a point and the value of an objective function at this point.Simple implementation of theRealConvergenceChecker
interface using only point coordinates.Simple implementation of theRealConvergenceChecker
interface using only objective function values.Simple implementation of theVectorialConvergenceChecker
interface using only point coordinates.Simple implementation of theVectorialConvergenceChecker
interface using only objective function values.Interface for (univariate real) optimization algorithms.This interface specifies how to check if aoptimization algorithm
has converged.This class holds a point and the vectorial value of an objective function at this point.