java.util.concurrent.ThreadLocalRandom#nextGaussian ( )源码实例Demo

public void run(SourceContext<MonitoringEvent> sourceContext) throws Exception {
    while (running) {
        MonitoringEvent monitoringEvent;

        final ThreadLocalRandom random = ThreadLocalRandom.current();

        if (shard > 0) {
            int rackId = random.nextInt(shard) + offset;

            if (random.nextDouble() >= temperatureRatio) {
                double power = random.nextGaussian() * powerStd + powerMean;
                monitoringEvent = new PowerEvent(rackId, power);
            } else {
                double temperature = random.nextGaussian() * temperatureStd + temperatureMean;
                monitoringEvent = new TemperatureEvent(rackId, temperature);
            }


            sourceContext.collect(monitoringEvent);
        }

        Thread.sleep(pause);
    }
}
 

/**
 * Fills a subset of the null
 *
 * @param geneChi2SumNull vector to fill will null chi2 values
 * @param eigenValues
 * @param randomChi2 reference distribution
 * @param start zero based count
 * @param stop zero based count, so must be < nrPermutation @return @param
 * rnd @pa r am eigenValuesLengt h
 */
public static void runPermutationsUsingEigenValues(final double[] geneChi2SumNull, final double[] eigenValues, double[] randomChi2, final int start, final int stop, final ThreadLocalRandom rnd, final int eigenValuesLength) {

	final int randomChi2Size = randomChi2.length;

	//LOGGER.debug("start: " + start + " stop: " + stop);
	int i = start;
	for (int perm = start; perm < stop; perm++) {
		double weightedChi2Perm = 0;
		for (int g = 0; g < eigenValuesLength; g++) {

			if (i < randomChi2Size) {
				weightedChi2Perm += eigenValues[g] * randomChi2[i++];
			} else {
				double randomZ = rnd.nextGaussian();
				weightedChi2Perm += eigenValues[g] * (randomZ * randomZ);
			}

		}
		geneChi2SumNull[perm] = weightedChi2Perm;
	}

}
 

private int generatePlanetDiameter(int position) {
  ThreadLocalRandom random = ThreadLocalRandom.current();
  double x = Math.abs(8 - position);
  double mean = 200.0 - 10.0 * x;
  double sd = 60.0 - 5.0 * x;
  double numFields = mean + sd * random.nextGaussian();
  numFields = Math.max(numFields, 42.0);
  return (int) (Math.sqrt(numFields) * 100.0) * 10;
}
 

private int generateTemperature(int position) {
  ThreadLocalRandom random = ThreadLocalRandom.current();
  double x = 8 - position;
  double mean = 30.0 + 1.75 * Math.signum(x) * x * x;
  int temperature = (int) (mean + 10.0 * random.nextGaussian());
  return Math.max(-60, Math.min(120, temperature));
}
 

@Override
public double[] call() throws Exception {
    ThreadLocalRandom rnd = ThreadLocalRandom.current();
    double[] geneChi2SumNull = new double[nrPermsThisTask];
    for (int perm=0; perm<nrPermsThisTask; perm++) {
        double weightedChi2Perm = 0;
        for (int g=0; g<eigenValues.length; g++) {
            double randomZ = rnd.nextGaussian();
            weightedChi2Perm+=eigenValues[g] * randomZ * randomZ;
        }
        geneChi2SumNull[perm]=weightedChi2Perm;
    } 
    return geneChi2SumNull;
}