List of usage examples for org.apache.commons.math.random RandomGenerator nextDouble
double nextDouble();
double value between 0.0 and 1.0 from this random number generator's sequence. From source file:de.tud.kom.p2psim.impl.network.modular.st.latency.NormalDistributionLatency.java
/** * Precompute the delays.// ww w . j a v a2s .co m * * @param size * The number of delays, which should be computed and stored in * delays. */ private void createDelays(int size) { if (propagationMeanDelay < standardDeviation) { log.warn( "Bad Configuration! It is possible, that huge delays are negative and consequently this values will be set to the mean delay value."); } log.info("Create " + size + " precomputed delays"); RandomGenerator randGen = Simulator.getRandom(); delays = new Vector<Long>(size); for (int i = 0; i < size; i++) { long delay = 0; try { delay = (long) normalDistribution.inverseCumulativeProbability(randGen.nextDouble()); } catch (MathException e) { log.error("MathException, check your parameteres for NormalDistributionLatency class...", e); throw new RuntimeException(); } if (delay <= 0) { log.debug("Set delay to propagationMeanDelay (" + propagationMeanDelay + ") because it has the value " + delay); delay = propagationMeanDelay; } delays.add(delay); } log.info("Finished, to create delays"); }
From source file:lfsom.visualization.clustering.LFSKMeans.java
/** * Calculate random centroids for each cluster. *///from w w w . j av a2s . c o m private void initClustersRandomly() { RandomGenerator rg = new JDKRandomGenerator(); // FIXME: this is for testing purposes only rg.setSeed(RANDOM_SEED); // for each cluster for (int clusterIndex = 0; clusterIndex < k; clusterIndex++) { // for each of its attributes double[] centroid = new double[numberOfAttributes]; for (int attributeIndex = 0; attributeIndex < numberOfAttributes; attributeIndex++) { centroid[attributeIndex] = differences[attributeIndex] * rg.nextDouble() + minValues[attributeIndex]; } clusters[clusterIndex] = new LFSCluster(centroid); } System.out.println("initial centroids: "); // printCentroids(); }
From source file:org.peerfact.impl.network.modular.common.PingErToolkitTest.java
@Test public void test1() { double avgRtt = 243.23d; double minRtt = 193.7d; double dVar = 10.78; long startTime = System.nanoTime(); JitterParameter result = PingErToolkit.getJitterParameterFrom(avgRtt, minRtt, dVar); log.debug("Calculation lasted " + (System.nanoTime() - startTime) * 0.000001 + " ms"); LognormalDist testDist = new LognormalDist(1, 0.6); RandomGenerator rand = new JDKRandomGenerator(); for (int i = 0; i < 100; i++) { log.debug(testDist.inverseF(rand.nextDouble())); }//from w w w .jav a 2 s.c o m log.debug(result); }