Example usage for java.lang Math random

List of usage examples for java.lang Math random

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Introduction

In this page you can find the example usage for java.lang Math random.

Prototype

public static double random()

Source Link

Document

Returns a double value with a positive sign, greater than or equal to 0.0 and less than 1.0 .

Usage

From source file:io.lightlink.output.JsonStreamTestPerf.java

private HashMap<String, Object> getData() {
    HashMap<String, Object> map = new HashMap<String, Object>();
    map.put("value1", Math.random());
    map.put("value2", "" + Math.random());
    map.put("value3", "" + Math.random());
    map.put("value5", "" + Math.random());
    map.put("value6", "" + Math.random());
    map.put("value7", "" + Math.random());
    map.put("value8", "" + Math.random());
    map.put("value9", "" + Math.random());
    map.put("value10", "" + Math.random());
    return map;/* w  ww . jav  a  2  s . c  o  m*/
}

From source file:edu.umass.cs.utils.Util.java

public static boolean oneIn(int n) {
    return Math.random() < 1.0 / Math.max(1, n) ? true : false;
}

From source file:com.github.hdl.tensorflow.yarn.app.ClusterSpec.java

private ClusterSpec(int workerServers, int psServers) {
    this.setNumTotalParameterServers(psServers);
    this.setNumTotalWorkerServers(workerServers);
    workers = new HashMap<>();
    paramServers = new HashMap<>();
    serverPortNext = PORT_FLOOR + ((int) (Math.random() * (PORT_CEILING - PORT_FLOOR)) + 1);
}

From source file:edu.indiana.d2i.htrc.skmeans.StreamingKMeansDriver.java

private void StreamingKMeansConfigHelper(Configuration conf, String input, int maxCluster) throws IOException {
    // get samples to calculate scale factor
    FileSystem fs = FileSystem.get(conf);
    FileStatus[] status = fs.listStatus(new Path(input), Utilities.HIDDEN_FILE_FILTER);
    int index = 0 + (int) (Math.random() * (status.length));
    SequenceFile.Reader seqReader = new SequenceFile.Reader(fs, status[index].getPath(), conf);

    int count = 0;
    Text key = new Text();
    VectorWritable value = new VectorWritable();
    List<MatrixSlice> slices = new ArrayList<MatrixSlice>();
    while (seqReader.next(key, value) && count < samplesNum) {
        MatrixSlice slice = new MatrixSlice(value.get().clone(), count);
        slices.add(slice);/*from  ww  w .j av  a  2 s .c  om*/
        count++;
    }

    // set cutoff
    float cutoff = (float) StreamingKmeans.estimateCutoff(slices, samplesNum);
    conf.setFloat(StreamingKMeansConfigKeys.CUTOFF, cutoff);
    logger.info("Scale factor (cutoff) is: " + cutoff);

    // set vector dimension
    int dim = value.get().size();
    conf.setInt(StreamingKMeansConfigKeys.VECTOR_DIMENSION, dim);
    logger.info("Dimemsion of a vector is: " + dim);

    // set maximum #cluster
    conf.setInt(StreamingKMeansConfigKeys.MAXCLUSTER, maxCluster);

    // set distance measurement
    conf.set(StreamingKMeansConfigKeys.DIST_MEASUREMENT, EuclideanDistanceMeasure.class.getName());
}

From source file:com.galenframework.ide.model.SizeVariation.java

public List<Dimension> generateVariations() {
    if (end == null || iterations < 2) {
        return asList(start.toSeleniumDimension());
    } else {//ww  w  .j  a v a2 s . co m
        List<Dimension> sizes = new LinkedList<>();

        int deltaWidth = end.getWidth() - start.getWidth();
        int deltaHeight = end.getHeight() - start.getHeight();
        int maxDistance = Math.max(Math.abs(deltaWidth), Math.abs(deltaHeight));

        int amount = Math.min(maxDistance, iterations);

        if (amount > 0) {
            int randomWidthDelta = 0;
            int randomHeightDelta = 0;

            for (int i = 0; i < amount; i++) {
                if (random) {
                    randomWidthDelta = (int) (Math.random() * deltaWidth / amount);
                    randomHeightDelta = (int) (Math.random() * deltaHeight / amount);
                }

                int w = (int) Math.floor(start.getWidth() + deltaWidth * i / amount + randomWidthDelta);
                int h = (int) Math.floor(start.getHeight() + deltaHeight * i / amount + randomHeightDelta);
                sizes.add(new Dimension(w, h));
            }
        } else {
            sizes.add(new Dimension(start.getWidth(), start.getHeight()));
        }
        return sizes;
    }
}

From source file:com.ciphertool.genetics.algorithms.mutation.ConservativeMutationAlgorithm.java

/**
 * Performs a genetic mutation of a random Gene of the supplied Chromosome
 * /*from w w w  .j a  v a  2 s  .c o  m*/
 * @param chromosome
 *            the Chromosome to mutate
 */
private Integer mutateRandomGene(Chromosome chromosome, List<Integer> geneIndices) {
    int randomIndex;

    // We don't want to reuse an index, so loop until we find a new one
    int attempts = 0;
    do {
        randomIndex = (int) (Math.random() * chromosome.getGenes().size());

        attempts++;

        if (attempts >= MAX_FIND_ATTEMPTS) {
            if (log.isDebugEnabled()) {
                log.debug("Unable to find a previously unused Gene index after " + attempts
                        + " attempts.  Returning null.");
            }

            return null;
        }
    } while (geneIndices.contains(randomIndex));

    mutateGene(chromosome, randomIndex);

    return randomIndex;
}

From source file:org.dataconservancy.ui.it.support.CreateIdApiRequestIT.java

/**
 * Generates {@link #countToGenerate} ids, and insures that they are all unique.
 *
 * @throws Exception/*from  ww w .  j  a v a  2 s . c  o m*/
 */
@Test
public void testGenerateUniqueIdsSingleThread() throws Exception {
    long start = Calendar.getInstance().getTimeInMillis();
    for (int i = 0; i < countToGenerate; i++) {
        // Select an ID type to generate, based on a randomized seed.
        double seed = Math.random();
        log.trace("Seed is {}", seed);
        Types t = selectType(seed, Types.values());
        log.trace("Selected type {} with seed value {}", t, seed);

        // If debugging is enabled, keep track of the number of ids created for each type.
        if (log.isDebugEnabled()) {
            if (idTypeDistribution.containsKey(t)) {
                idTypeDistribution.get(t).getAndAdd(1);
            } else {
                idTypeDistribution.put(t, new AtomicInteger(1));
            }
        }

        // Create an ID, and keep it in a Set.
        generatedIds.add(reqFactory.createIdApiRequest(t).execute(hc));
    }

    if (log.isDebugEnabled()) {
        StringBuilder sb = new StringBuilder("ID distribution:\n");
        int totalGenerated = 0;
        for (Types t : Types.values()) {
            final Integer typeTotal = idTypeDistribution.get(t).get();
            totalGenerated += typeTotal;
            sb.append("Type: ").append(t).append(" Count: ").append(typeTotal).append("\n");
        }
        sb.append("Total generated: ").append(totalGenerated).append("\n");
        sb.append("Unique generated: ").append(generatedIds.size()).append("\n");
        sb.append("Execution time: ").append(Calendar.getInstance().getTimeInMillis() - start).append(" ms\n");
        log.debug(sb.toString());
    }

    // The number of generated IDs (stored in the Set) should equal 'countToGenerate'
    assertEquals("Expected " + countToGenerate + " to be generated, but the Set contained "
            + generatedIds.size() + ".  Some ids may not have been unique.", countToGenerate,
            generatedIds.size());
}

From source file:org.jfree.chart.demo.LineChartDemo3.java

/**
 * Creates a new demo./*from   w w  w.j a v  a2  s .  c o m*/
 *
 * @param title  the frame title.
 */
public LineChartDemo3(final String title) {

    super(title);

    // create a dataset...
    final XYSeriesCollection dataset = new XYSeriesCollection();
    for (int i = 0; i < 10; i++) {
        final XYSeries series = new XYSeries("S" + i);
        for (int j = 0; j < 10; j++) {
            series.add(j, Math.random() * 100);
        }
        dataset.addSeries(series);
    }

    final JFreeChart chart = createChart(dataset);

    // add the chart to a panel...
    final ChartPanel chartPanel = new ChartPanel(chart);
    chartPanel.setPreferredSize(new java.awt.Dimension(500, 270));
    setContentPane(chartPanel);

}

From source file:emlab.domain.factory.ElectricityProducerFactory.java

@Transactional
private PowerPlant createPowerPlant(PowerGeneratingTechnology technology, EnergyProducer energyProducer,
        PowerGridNode location) {/*from w ww.j  av a 2s  .  c  o  m*/
    PowerPlant plant = new PowerPlant().persist();
    String label = energyProducer.getName() + " - " + technology.getName();
    plant.setName(label);
    plant.setTechnology(technology);
    plant.setOwner(energyProducer);
    plant.setLocation(location);
    plant.setConstructionStartTime(-(technology.getExpectedLeadtime() + technology.getExpectedPermittime()
            + Math.round((Math.random() * technology.getExpectedLifetime()))) + 2); // TODO: Why include expected lead
                                                                                                                                                                                           // time and permit time? Wouldn't it
                                                                                                                                                                                           // be realistic to have some PP in
                                                                                                                                                                                           // the pipeline at the start?
    plant.setActualLeadtime(plant.getTechnology().getExpectedLeadtime());
    plant.setActualPermittime(plant.getTechnology().getExpectedPermittime());
    plant.setExpectedEndOfLife(plant.getConstructionStartTime() + plant.getActualPermittime()
            + plant.getActualLeadtime() + plant.getTechnology().getExpectedLifetime());
    plant.calculateAndSetActualInvestedCapital(plant.getConstructionStartTime());
    plant.calculateAndSetActualEfficiency(plant.getConstructionStartTime());
    plant.setDismantleTime(1000);
    Loan loan = new Loan().persist();
    loan.setFrom(energyProducer);
    loan.setTo(null);
    double amountPerPayment = determineLoanAnnuities(
            plant.getActualInvestedCapital() * energyProducer.getDebtRatioOfInvestments(),
            plant.getTechnology().getDepreciationTime(), energyProducer.getLoanInterestRate());
    loan.setAmountPerPayment(amountPerPayment);
    loan.setTotalNumberOfPayments(plant.getTechnology().getDepreciationTime());
    loan.setLoanStartTime(plant.getConstructionStartTime());
    loan.setNumberOfPaymentsDone(-plant.getConstructionStartTime());// Some
                                                                    // payments
                                                                    // are
                                                                    // already
                                                                    // made
    plant.setLoan(loan);
    return plant;
}

From source file:com.espertech.esper.multithread.TestMTContextListenerDispatch.java

private void tryPerformanceDispatch(int numThreads, int numRepeats) throws Exception {
    MyListener listener = new MyListener();
    engine.getEPAdministrator().getStatement("select").addListener(listener);

    List<Object>[] events = new ArrayList[numThreads];
    int eventId = 0;
    for (int threadNum = 0; threadNum < numThreads; threadNum++) {
        events[threadNum] = new ArrayList<Object>();
        for (int eventNum = 0; eventNum < numRepeats; eventNum++) {
            // range: 1 to 1000
            int partition = (int) (Math.random() * 50);
            eventId++;//from www  .j  a va  2s  .  co  m
            events[threadNum].add(new SupportBean(new Integer(partition).toString(), eventId));
        }
    }

    ExecutorService threadPool = Executors.newFixedThreadPool(numThreads);
    Future futures[] = new Future[numThreads];
    long startTime = System.currentTimeMillis();

    for (int i = 0; i < numThreads; i++) {
        Callable callable = new SendEventCallable(i, engine, events[i].iterator());
        futures[i] = threadPool.submit(callable);
    }
    for (Future future : futures) {
        assertEquals(true, future.get());
    }
    long delta = System.currentTimeMillis() - startTime;

    threadPool.shutdown();
    threadPool.awaitTermination(10, TimeUnit.SECONDS);

    // print those events not received
    for (List<Object> eventList : events) {
        for (Object event : eventList) {
            if (!listener.getBeans().contains(event)) {
                log.info("Expected event was not received, event " + event);
            }
        }
    }

    assertEquals(numRepeats * numThreads, listener.getBeans().size());
    assertTrue("delta=" + delta, delta < 500);
}