Double[] suffix = {(double) 86, (double) 99};
      Double[] all = concat(concat(prefix, elements), suffix);
      return asList(all).subList(2, elements.length + 2);
    }
  }

  private static Double[] concat(Double[] left, Double[] right) {
    Double[] result = new Double[left.length + right.length];
    System.arraycopy(left, 0, result, 0, left.length);

      Double[] suffix = {(double) 86, (double) 99};
      Double[] all = concat(concat(prefix, elements), suffix);
      return asList(all).subList(2, elements.length + 2);
    }
  }

  private static Double[] concat(Double[] left, Double[] right) {
    Double[] result = new Double[left.length + right.length];
    System.arraycopy(left, 0, result, 0, left.length);

    KAHAN {
      @Override
      double mean(double[] values) {
        double sum = 0.0;
        double c = 0.0;
        for (double value : values) {
          double y = value - c;
          double t = sum + y;
          c = (t - sum) - y;
          sum = t;
        }
        return sum / values.length;
      }
    },
    KNUTH {
      @Override
      double mean(double[] values) {
        double mean = values[0];

    KAHAN {
      @Override
      double mean(double[] values) {
        double sum = 0.0;
        double c = 0.0;
        for (double value : values) {
          double y = value - c;
          double t = sum + y;
          c = (t - sum) - y;
          sum = t;
        }
        return sum / values.length;
      }
    },
    KNUTH {
      @Override
      double mean(double[] values) {
        double mean = values[0];

 * Double#doubleToRawLongBits}, which differs from both the primitive double {@code ==} operator and
 * from {@link Double#equals}, as if implemented by:
 *
 * <pre>{@code
 * static boolean bitEquals(double x, double y) {
 *   long xBits = Double.doubleToRawLongBits(x);
 *   long yBits = Double.doubleToRawLongBits(y);
 *   return xBits == yBits;
 * }
 * }</pre>
 *
 * @author Doug Lea
 * @author Martin Buchholz
 * @since 11.0
 */

    for (double positiveValue : POSITIVE_FINITE_DOUBLE_CANDIDATES) {
      assertEquals(positiveValue, DoubleUtils.ensureNonNegative(positiveValue));
      assertEquals(0.0, DoubleUtils.ensureNonNegative(-positiveValue));
    }
    assertEquals(Double.POSITIVE_INFINITY, DoubleUtils.ensureNonNegative(Double.POSITIVE_INFINITY));
    assertEquals(0.0, DoubleUtils.ensureNonNegative(Double.NEGATIVE_INFINITY));

     * @param pattern
     *            パターン文字列
     * @return 変換された{@link Double}
     */
    public static Double toDouble(final Object o, final String pattern) {
        if (o == null) {
            return null;
        } else if (o instanceof Double) {
            return (Double) o;
        } else if (o instanceof Number) {
            return new Double(((Number) o).doubleValue());
        } else if (o instanceof String) {

  private static final double[] VALUES = {
    Double.NEGATIVE_INFINITY,
    -Double.MAX_VALUE,
    (double) Long.MIN_VALUE,
    (double) Integer.MIN_VALUE,
    -Math.PI,
    -1.0,
    -Double.MIN_VALUE,
    -0.0,
    +0.0,
    Double.MIN_VALUE,
    1.0,
    Math.PI,
    (double) Integer.MAX_VALUE,
    (double) Long.MAX_VALUE,
    Double.MAX_VALUE,
    Double.POSITIVE_INFINITY,

  public void testCheckNonNegative_zeroDouble() {
    MathPreconditions.checkNonNegative("double", 0d);
  }

  public void testCheckNonNegative_maxDouble() {
    MathPreconditions.checkNonNegative("double", Double.MAX_VALUE);
  }

  public void testCheckNonNegative_minDouble() {
    MathPreconditions.checkNonNegative("double", Double.MIN_VALUE);
  }

  public void testCheckNonNegative_positiveDouble() {

  @Param QuantilesAlgorithm algorithm;

  private double[][] datasets = new double[0x100][];

  @BeforeExperiment
  void setUp() {
    Random rng = new Random();
    for (int i = 0; i < 0x100; i++) {
      datasets[i] = new double[datasetSize];
      for (int j = 0; j < datasetSize; j++) {
        datasets[i][j] = rng.nextDouble();
      }
    }
  }

  private double[] dataset(int i) {