Example usage for org.apache.commons.math3.fitting.leastsquares LeastSquaresBuilder LeastSquaresBuilder

List of usage examples for org.apache.commons.math3.fitting.leastsquares LeastSquaresBuilder LeastSquaresBuilder

Introduction

In this page you can find the example usage for org.apache.commons.math3.fitting.leastsquares LeastSquaresBuilder LeastSquaresBuilder.

Prototype

LeastSquaresBuilder

Source Link

Usage

From source file:org.orekit.utils.SecularAndHarmonic.java

/** Fit parameters.
 * @see #getFittedParameters()/*from w w  w.jav  a  2 s.c o m*/
 */
public void fit() {

    final AbstractCurveFitter fitter = new AbstractCurveFitter() {
        /** {@inheritDoc} */
        @Override
        protected LeastSquaresProblem getProblem(final Collection<WeightedObservedPoint> observations) {
            // Prepare least-squares problem.
            final int len = observations.size();
            final double[] target = new double[len];
            final double[] weights = new double[len];

            int i = 0;
            for (final WeightedObservedPoint obs : observations) {
                target[i] = obs.getY();
                weights[i] = obs.getWeight();
                ++i;
            }

            final AbstractCurveFitter.TheoreticalValuesFunction model = new AbstractCurveFitter.TheoreticalValuesFunction(
                    new LocalParametricFunction(), observations);

            // build a new least squares problem set up to fit a secular and harmonic curve to the observed points
            return new LeastSquaresBuilder().maxEvaluations(Integer.MAX_VALUE).maxIterations(Integer.MAX_VALUE)
                    .start(fitted).target(target).weight(new DiagonalMatrix(weights))
                    .model(model.getModelFunction(), model.getModelFunctionJacobian()).build();

        }
    };

    fitted = fitter.fit(observedPoints);

}

From source file:uk.ac.diamond.scisoft.analysis.optimize.ApacheOptimizer.java

/**
 * create a multivariateJacobianFunction from MVF and MMF (using builder?)
 * /*  www  . j  a  v a 2 s  .  c o m*/
 */
private void internalLeastSquaresOptimize() {
    LeastSquaresOptimizer opt = createLeastSquaresOptimizer();

    try {

        LeastSquaresBuilder builder = new LeastSquaresBuilder().model(createJacobianFunction())
                .target(data.getData()).start(getParameterValues()).lazyEvaluation(false)
                .maxEvaluations(MAX_EVAL).maxIterations(MAX_ITER);

        builder.checker(new EvaluationRmsChecker(REL_TOL, ABS_TOL));

        if (weight != null) {
            builder.weight(MatrixUtils.createRealDiagonalMatrix(weight.getData()));
        }

        // TODO add checker, validator
        LeastSquaresProblem problem = builder.build();

        Optimum result = opt.optimize(problem);

        RealVector res = result.getPoint();
        setParameterValues(
                res instanceof ArrayRealVector ? ((ArrayRealVector) res).getDataRef() : res.toArray());
        try {
            RealVector err = result.getSigma(1e-14);

            //            sqrt(S / (n - m) * C[i][i]);
            double c = result.getCost();
            int n = data.getSize();
            int m = getParameterValues().length;

            double[] s = err instanceof ArrayRealVector ? ((ArrayRealVector) err).getDataRef() : err.toArray();

            errors = new double[s.length];

            for (int i = 0; i < errors.length; i++)
                errors[i] = Math.sqrt(((c * c) / ((n - m)) * (s[i] * s[i])));

        } catch (SingularMatrixException e) {
            logger.warn("Could not find errors as covariance matrix was singular");
        }

        logger.trace("Residual: {} from {}", result.getRMS(), Math.sqrt(calculateResidual()));
    } catch (Exception e) {
        logger.error("Problem with least squares optimizer", e);
        throw new IllegalArgumentException("Problem with least squares optimizer");
    }
}