Package org.apache.commons.math4.legacy.fitting

Class SimpleCurveFitter

java.lang.Object

org.apache.commons.math4.legacy.fitting.AbstractCurveFitter

org.apache.commons.math4.legacy.fitting.SimpleCurveFitter

Direct Known Subclasses:

GaussianCurveFitter, HarmonicCurveFitter, PolynomialCurveFitter

public class SimpleCurveFitter
extends AbstractCurveFitter

Fits points to a user-defined function.

Since:

3.4

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	SimpleCurveFitter.ParameterGuesser	Guesses the parameters.

Nested classes/interfaces inherited from class org.apache.commons.math4.legacy.fitting.AbstractCurveFitter

AbstractCurveFitter.TheoreticalValuesFunction

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	SimpleCurveFitter(ParametricUnivariateFunction function, double[] initialGuess, SimpleCurveFitter.ParameterGuesser guesser, int maxIter)	Constructor used by the factory methods.

Method Summary

Modifier and Type	Method	Description
static SimpleCurveFitter	create(ParametricUnivariateFunction f, double[] start)	Creates a curve fitter.
static SimpleCurveFitter	create(ParametricUnivariateFunction f, SimpleCurveFitter.ParameterGuesser guesser)	Creates a curve fitter.
protected LeastSquaresProblem	getProblem(Collection<WeightedObservedPoint> observations)	Creates a least squares problem corresponding to the appropriate curve.
SimpleCurveFitter	withMaxIterations(int newMaxIter)	Configure the maximum number of iterations.
SimpleCurveFitter	withStartPoint(double[] newStart)	Configure the start point (initial guess).

Methods inherited from class org.apache.commons.math4.legacy.fitting.AbstractCurveFitter

fit, getOptimizer

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleCurveFitter

protected SimpleCurveFitter(ParametricUnivariateFunction function,
                            double[] initialGuess,
                            SimpleCurveFitter.ParameterGuesser guesser,
                            int maxIter)

Constructor used by the factory methods.

Parameters:

function - Function to fit.

initialGuess - Initial guess. Cannot be null. Its length must be consistent with the number of parameters of the function to fit.

guesser - Method for providing an initial guess (if initialGuess is null).

maxIter - Maximum number of iterations of the optimization algorithm.

Method Detail

create

public static SimpleCurveFitter create(ParametricUnivariateFunction f,
                                       double[] start)

Creates a curve fitter. The maximum number of iterations of the optimization algorithm is set to Integer.MAX_VALUE.

Parameters:

f - Function to fit.

start - Initial guess for the parameters. Cannot be null. Its length must be consistent with the number of parameters of the function to fit.

Returns:

a curve fitter.

See Also:

withStartPoint(double[]), withMaxIterations(int)

create

public static SimpleCurveFitter create(ParametricUnivariateFunction f,
                                       SimpleCurveFitter.ParameterGuesser guesser)

Creates a curve fitter. The maximum number of iterations of the optimization algorithm is set to Integer.MAX_VALUE.

Parameters:

f - Function to fit.

guesser - Method for providing an initial guess.

Returns:

a curve fitter.

See Also:

withStartPoint(double[]), withMaxIterations(int)

withStartPoint

public SimpleCurveFitter withStartPoint(double[] newStart)

Configure the start point (initial guess).

Parameters:

newStart - new start point (initial guess)

Returns:

a new instance.

withMaxIterations

public SimpleCurveFitter withMaxIterations(int newMaxIter)

Configure the maximum number of iterations.

Parameters:

newMaxIter - maximum number of iterations

Returns:

a new instance.

getProblem

protected LeastSquaresProblem getProblem(Collection<WeightedObservedPoint> observations)

Creates a least squares problem corresponding to the appropriate curve.

Specified by:

getProblem in class AbstractCurveFitter

Parameters:

observations - Sample points.

Returns:

the least squares problem to use for fitting the curve to the given points.