List of usage examples for java.util Random nextDouble
public double nextDouble()
From source file:at.illecker.hama.hybrid.examples.summation.SummationBSP.java
static BigDecimal writeSummationInputFile(FileSystem fs, Path dir, int fileCount) throws IOException { BigDecimal sum = new BigDecimal(0); Random rand = new Random(); double rangeMin = 0; double rangeMax = 100; for (int i = 0; i < fileCount; i++) { DataOutputStream out = fs.create(new Path(dir, "part" + i)); // loop between 50 and 149 times for (int j = 0; j < rand.nextInt(100) + 50; j++) { // generate key value pair inputs double randomValue = rangeMin + (rangeMax - rangeMin) * rand.nextDouble(); String truncatedValue = new BigDecimal(randomValue) .setScale(DOUBLE_PRECISION, BigDecimal.ROUND_DOWN).toString(); String line = "key" + (j + 1) + "\t" + truncatedValue + "\n"; out.writeBytes(line);/*from w ww . j a va 2 s . c om*/ sum = sum.add(new BigDecimal(truncatedValue)); LOG.debug("input[" + j + "]: '" + line + "' sum: " + sum.toString()); } out.close(); } return sum; }
From source file:com.linkedin.pinot.core.segment.index.creator.RawIndexCreatorTest.java
/** * Helper method that generates a random value for a given data type * * @param dataType Data type for which to generate the random value * @return Random value for the data type. */// www . j av a 2s. c o m public static Object getRandomValue(Random random, FieldSpec.DataType dataType) { Object value; switch (dataType) { case INT: value = random.nextInt(); break; case LONG: value = random.nextLong(); break; case FLOAT: value = random.nextFloat(); break; case DOUBLE: value = random.nextDouble(); break; case STRING: value = StringUtil .trimTrailingNulls(RandomStringUtils.random(random.nextInt(MAX_STRING_LENGTH_IN_BYTES))); break; default: throw new IllegalArgumentException("Illegal data type for random value generator: " + dataType); } return value; }
From source file:org.apache.hadoop.hbase.rest.TestScannerResource.java
static int insertData(Configuration conf, String tableName, String column, double prob) throws IOException { Random rng = new Random(); int count = 0; HTable table = new HTable(conf, tableName); byte[] k = new byte[3]; byte[][] famAndQf = KeyValue.parseColumn(Bytes.toBytes(column)); for (byte b1 = 'a'; b1 < 'z'; b1++) { for (byte b2 = 'a'; b2 < 'z'; b2++) { for (byte b3 = 'a'; b3 < 'z'; b3++) { if (rng.nextDouble() < prob) { k[0] = b1;//from w ww . jav a 2 s . c om k[1] = b2; k[2] = b3; Put put = new Put(k); put.setDurability(Durability.SKIP_WAL); put.add(famAndQf[0], famAndQf[1], k); table.put(put); count++; } } } } table.flushCommits(); table.close(); return count; }
From source file:it.units.malelab.ege.util.Utils.java
public static <T> T selectRandom(Map<T, Double> options, Random random) { double sum = 0; for (Double rate : options.values()) { sum = sum + rate;/*from w w w .java2 s . c o m*/ } double d = random.nextDouble() * sum; for (Map.Entry<T, Double> option : options.entrySet()) { if (d < option.getValue()) { return option.getKey(); } d = d - option.getValue(); } return (T) options.keySet().toArray()[0]; }
From source file:org.apache.hama.pipes.TestPipes.java
static double[][] createRandomMatrix(int rows, int columns, Random rand) { final double[][] matrix = new double[rows][columns]; double rangeMin = 0; double rangeMax = 100; for (int i = 0; i < rows; i++) { for (int j = 0; j < columns; j++) { double randomValue = rangeMin + (rangeMax - rangeMin) * rand.nextDouble(); matrix[i][j] = new BigDecimal(randomValue).setScale(DOUBLE_PRECISION, BigDecimal.ROUND_DOWN) .doubleValue();/*from w ww. ja v a 2s. c o m*/ } } return matrix; }
From source file:org.apache.sysml.utils.lite.BuildLiteExecution.java
public static double[][] randomMatrix(int rows, int cols, double min, double max, double sparsity) { double[][] matrix = new double[rows][cols]; Random random = new Random(System.currentTimeMillis()); for (int i = 0; i < rows; i++) { for (int j = 0; j < cols; j++) { if (random.nextDouble() > sparsity) { continue; }/*from w w w . j a v a 2 s.c o m*/ matrix[i][j] = (random.nextDouble() * (max - min) + min); } } return matrix; }
From source file:lirmm.inria.fr.math.BigSparseRealMatrix.java
/** * Generate a matrix of random values./*w w w.ja v a 2 s . c om*/ * * @param rowDimension Number of rows of the matrix. * @param columnDimension Number of columns of the matrix. * @return An instance of BigSparseRealMatrix. */ public static BigSparseRealMatrix randomGenerateMatrix(int rowDimension, int columnDimension) { BigSparseRealMatrix m = new BigSparseRealMatrix(rowDimension, columnDimension); Random r = new Random(); for (int i = 0; i < rowDimension; i++) { for (int j = 0; j < columnDimension; j++) { m.setEntry(i, j, r.nextDouble()); } } return m; }
From source file:org.apache.hama.pipes.TestPipes.java
static BigDecimal writeSummationInputFile(FileSystem fs, Path dir) throws IOException { DataOutputStream out = fs.create(new Path(dir, "part0")); Random rand = new Random(); double rangeMin = 0; double rangeMax = 100; BigDecimal sum = new BigDecimal(0); // loop between 50 and 149 times for (int i = 0; i < rand.nextInt(100) + 50; i++) { // generate key value pair inputs double randomValue = rangeMin + (rangeMax - rangeMin) * rand.nextDouble(); String truncatedValue = new BigDecimal(randomValue).setScale(DOUBLE_PRECISION, BigDecimal.ROUND_DOWN) .toString();/*from w w w. ja v a 2 s .c om*/ String line = "key" + (i + 1) + "\t" + truncatedValue + "\n"; out.writeBytes(line); sum = sum.add(new BigDecimal(truncatedValue)); } out.close(); return sum; }
From source file:org.deeplearning4j.datasets.canova.RecordReaderDataSetiteratorTest.java
public static double[][] makeRandomCSV(String tempFile, int nLines, int nFeatures) { File temp = new File(tempFile); temp.deleteOnExit();//from w w w . ja v a 2 s .c om Random rand = new Random(12345); double[][] dArr = new double[nLines][nFeatures + 1]; try (PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter(temp)))) { for (int i = 0; i < nLines; i++) { dArr[i][0] = rand.nextDouble(); //First column: label out.print(dArr[i][0]); for (int j = 0; j < nFeatures; j++) { dArr[i][j + 1] = rand.nextDouble(); out.print("," + dArr[i][j + 1]); } out.println(); } } catch (IOException e) { e.printStackTrace(); } return dArr; }
From source file:com.twitter.graphjet.bipartite.MultiSegmentPowerLawBipartiteGraphTest.java
/** * Build a random left-regular bipartite graph of given left and right sizes. * * @param leftSize is the left hand size of the bipartite graph * @param rightSize is the right hand size of the bipartite graph * @param random is the random number generator to use for constructing the graph * @return a random bipartite graph//from w w w. ja v a 2s . co m */ public static MultiSegmentPowerLawBipartiteGraph buildRandomMultiSegmentBipartiteGraph(int maxNumSegments, int maxNumEdgesPerSegment, int leftSize, int rightSize, double edgeProbability, Random random) { MultiSegmentPowerLawBipartiteGraph multiSegmentPowerLawBipartiteGraph = new MultiSegmentPowerLawBipartiteGraph( maxNumSegments, maxNumEdgesPerSegment, leftSize / 2, (int) (rightSize * edgeProbability / 2), 2.0, rightSize / 2, (int) (leftSize * edgeProbability / 2), 2.0, new IdentityEdgeTypeMask(), new NullStatsReceiver()); for (int i = 0; i < leftSize; i++) { for (int j = 0; j < rightSize; j++) { if (random.nextDouble() < edgeProbability) { multiSegmentPowerLawBipartiteGraph.addEdge(i, j, (byte) 0); } } } return multiSegmentPowerLawBipartiteGraph; }