Example usage for org.apache.commons.math3.distribution ParetoDistribution sample

Introduction

In this page you can find the example usage for org.apache.commons.math3.distribution ParetoDistribution sample.

Prototype

public double[] sample(int sampleSize) 

Source Link

Document

The default implementation generates the sample by calling #sample() in a loop.

Usage

From source file:org.jboss.aerogear.unifiedpush.utils.installation.generation.ParetoInstallationDistribution.java

@Override
public MassInstallation generate(List<PushApplication> registeredApplications, int installationsCount) {

    ParetoDistribution paretoDistribution = new ParetoDistribution(PARETO_SCALE_PARAMETER,
            PARETO_SHAPE_PARAMETER);//w ww. j a  va2  s.c o  m

    List<Variant> variants = new ArrayList<Variant>();

    for (PushApplication pushApplication : registeredApplications) {
        variants.addAll(pushApplication.getVariants());
    }

    double[] distributionSample = paretoDistribution.sample(variants.size());

    double installationSum = sum(distributionSample);

    double[] installationsPerVariantFraction = new double[distributionSample.length];

    for (int i = 0; i < installationsPerVariantFraction.length; i++) {
        installationsPerVariantFraction[i] = distributionSample[i] / installationSum;
    }

    double[] installationsPerVariant = new double[distributionSample.length];

    for (int i = 0; i < installationsPerVariant.length; i++) {
        installationsPerVariant[i] = installationsPerVariantFraction[i] * installationsCount;
    }

    int[] installations = roundInstallationsCount(installationsPerVariant);

    MassInstallation massInstallation = new MassInstallation();

    for (int i = 0; i < variants.size(); i++) {
        Variant variant = variants.get(i);
        massInstallation.map.put(variant.getVariantID(),
                InstallationUtils.generate(variant.getType(), installations[i]));
    }

    return massInstallation;
}

---