@Test
 public void testReturnsWithZeroesInSeries() {
   final int n = 20;
   final LocalDate[] times = new LocalDate[n];
   final double[] data = new double[n];
   final double[] returns = new double[n - 3];
   double random;
   for (int i = 0; i < n - 2; i++) {
     times[i] = LocalDate.ofEpochDay(i);
     random = RANDOM.nextDouble();
     data[i] = random;
     if (i > 0) {
       returns[i - 1] = Math.log(random / data[i - 1]);
     }
   }
   times[n - 2] = LocalDate.ofEpochDay(n - 2);
   data[n - 2] = 0;
   times[n - 1] = LocalDate.ofEpochDay(n - 1);
   data[n - 1] = RANDOM.nextDouble();
   final LocalDateDoubleTimeSeries priceTS = ImmutableLocalDateDoubleTimeSeries.of(times, data);
   final LocalDateDoubleTimeSeries returnTS =
       ImmutableLocalDateDoubleTimeSeries.of(Arrays.copyOfRange(times, 1, n - 2), returns);
   final TimeSeriesReturnCalculator strict =
       new ContinuouslyCompoundedTimeSeriesReturnCalculator(CalculationMode.STRICT);
   final LocalDateDoubleTimeSeries[] tsArray = new LocalDateDoubleTimeSeries[] {priceTS};
   try {
     strict.evaluate(tsArray);
     Assert.fail();
   } catch (final TimeSeriesException e) {
     // Expected
   }
   final TimeSeriesReturnCalculator lenient =
       new ContinuouslyCompoundedTimeSeriesReturnCalculator(CalculationMode.LENIENT);
   assertTrue(lenient.evaluate(tsArray).equals(returnTS));
 }
 @Test
 public void test() {
   boolean isCall;
   double spot, strike, b, price;
   Expiry expiry;
   YieldAndDiscountCurve curve;
   EuropeanVanillaOptionDefinition definition;
   StandardOptionDataBundle initialData, data;
   double sigma = 0.01;
   for (int i = 0; i < 100; i++) {
     expiry = new Expiry(DateUtils.getDateOffsetWithYearFraction(DATE, RANDOM.nextDouble() * 2));
     sigma += 0.03;
     spot = 2 * RANDOM.nextDouble() + 10;
     strike = 2 * RANDOM.nextDouble() + 10;
     curve = YieldCurve.from(ConstantDoublesCurve.from(RANDOM.nextDouble() / 10));
     b = 0; // RANDOM.nextDouble() / 20;
     isCall = RANDOM.nextDouble() < 0.5 ? true : false;
     definition = new EuropeanVanillaOptionDefinition(strike, expiry, isCall);
     initialData = new StandardOptionDataBundle(curve, b, null, spot, DATE);
     data =
         new StandardOptionDataBundle(
             curve, b, new VolatilitySurface(ConstantDoublesSurface.from(sigma)), spot, DATE);
     price = BSM.getPricingFunction(definition).evaluate(data);
     assertEquals(
         sigma,
         MODEL
             .getSurface(
                 Collections.<OptionDefinition, Double>singletonMap(definition, price),
                 initialData)
             .getVolatility(DoublesPair.of(0., 0.)),
         EPS);
   }
 }
 static {
   for (int i = 0; i < N; i++) {
     X[i][0] = RANDOM.nextDouble();
     X[i][1] = RANDOM.nextDouble();
     X[i][2] = RANDOM.nextDouble();
   }
 }
 @Test
 public void test() {
   final int n = 20;
   final double[][] x = new double[n][5];
   final double[] y1 = new double[n];
   final double[] y2 = new double[n];
   final double[] a1 = new double[] {3.4, 1.2, -0.62, -0.44, 0.65};
   final double[] a2 = new double[] {0.98, 3.4, 1.2, -0.62, -0.44, 0.65};
   for (int i = 0; i < n; i++) {
     for (int j = 0; j < 5; j++) {
       x[i][j] = RANDOM.nextDouble() + (RANDOM.nextDouble() - 0.5) / FACTOR;
     }
     y1[i] =
         a1[0] * x[i][0]
             + a1[1] * x[i][1]
             + a1[2] * x[i][2]
             + a1[3] * x[i][3]
             + a1[4] * x[i][4]
             + RANDOM.nextDouble() / FACTOR;
     y2[i] =
         a2[0]
             + a2[1] * x[i][0]
             + a2[2] * x[i][1]
             + a2[3] * x[i][2]
             + a2[4] * x[i][3]
             + a2[5] * x[i][4]
             + RANDOM.nextDouble() / FACTOR;
   }
   final LeastSquaresRegressionResult result1 = REGRESSION.regress(x, null, y1, false);
   final LeastSquaresRegressionResult result2 = REGRESSION.regress(x, null, y2, true);
   assertRegression(result1, a1);
   assertRegression(result2, a2);
   final double[] residuals1 = result1.getResiduals();
   for (int i = 0; i < n; i++) {
     assertEquals(
         y1[i],
         a1[0] * x[i][0]
             + a1[1] * x[i][1]
             + a1[2] * x[i][2]
             + a1[3] * x[i][3]
             + a1[4] * x[i][4]
             + residuals1[i],
         10 * EPS);
   }
   final double[] residuals2 = result2.getResiduals();
   for (int i = 0; i < n; i++) {
     assertEquals(
         y2[i],
         a2[0]
             + a2[1] * x[i][0]
             + a2[2] * x[i][1]
             + a2[3] * x[i][2]
             + a2[4] * x[i][3]
             + a2[5] * x[i][4]
             + residuals2[i],
         10 * EPS);
   }
 }
 @Test
 public void testReturnsWithDividendsAtDifferentTimes() {
   final int n = 20;
   final LocalDate[] times = new LocalDate[n];
   final double[] data = new double[n];
   final double[] returns = new double[n - 1];
   double random;
   for (int i = 0; i < n; i++) {
     times[i] = LocalDate.ofEpochDay(i);
     random = RANDOM.nextDouble();
     data[i] = random;
     if (i > 0) {
       returns[i - 1] = Math.log(random / data[i - 1]);
     }
   }
   final LocalDateDoubleTimeSeries dividendTS =
       ImmutableLocalDateDoubleTimeSeries.of(
           new LocalDate[] {LocalDate.ofEpochDay(300)}, new double[] {3});
   final LocalDateDoubleTimeSeries priceTS = ImmutableLocalDateDoubleTimeSeries.of(times, data);
   final LocalDateDoubleTimeSeries returnTS =
       ImmutableLocalDateDoubleTimeSeries.of(Arrays.copyOfRange(times, 1, n), returns);
   assertTrue(
       CALCULATOR
           .evaluate(new LocalDateDoubleTimeSeries[] {priceTS, dividendTS})
           .equals(returnTS));
 }
 @Test(expectedExceptions = IllegalArgumentException.class)
 public void testNullData() {
   MODEL.getSurface(
       Collections.<OptionDefinition, Double>singletonMap(
           new EuropeanVanillaOptionDefinition(RANDOM.nextDouble(), new Expiry(DATE), true), 2.3),
       null);
 }
  @Test(expectedExceptions = IllegalArgumentException.class)
  public void wrongLengthTest() {
    final int nSamples = 10;
    final List<DoublesPair> points = new ArrayList<>(nSamples);
    final DoubleMatrix1D x = new DoubleMatrix1D(nSamples + 1);
    x.getData()[0] = RANDOM.nextDouble();
    for (int i = 0; i < nSamples; i++) {
      final double t = RANDOM.nextDouble() * 20.0;
      final double k = RANDOM.nextDouble() * 0.15;
      points.add(DoublesPair.of(t, k));
      x.getData()[i + 1] = RANDOM.nextDouble();
    }

    final DiscreteVolatilityFunctionProvider pro = new DiscreteVolatilityFunctionProviderDirect();
    final DiscreteVolatilityFunction func = pro.from(points);
    func.evaluate(x);
  }
 @Test
 public void test() {
   double x;
   final double eps = 1e-5;
   for (int i = 0; i < 100; i++) {
     x = RANDOM.nextDouble();
     assertEquals(x, F.evaluate(T.getCDF(x)), eps);
   }
 }
Esempio n. 9
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/**
 * Number generator that implements the RandomGenerator interface, and returns pseudo-random numbers
 * drawn from an empirical distribution. This class is primarily a wrapper for the Colt package's
 * Empirical class.
 */
public class RandomGenerator_Kernel implements RandomGenerator, Cloneable {

  private double[] weights = new double[] {.125, .250, .375, .5, .625, .75, .875, 1};
  private Empirical emp =
      new Empirical(weights, Empirical.LINEAR_INTERPOLATION, RandomEngine.makeDefault());
  private boolean rotate = true;
  private double inc = 1d / (weights.length * 2d);

  /** Returns a clone/copy of the instance. */
  @Override
  public RandomGenerator_Kernel clone() {
    RandomGenerator_Kernel rgk = new RandomGenerator_Kernel();
    rgk.weights = Arrays.copyOf(this.weights, weights.length);
    rgk.emp = (Empirical) emp.clone();
    rgk.rotate = rotate;
    rgk.inc = inc;
    return rgk;
  }

  /**
   * Returns the next pseudo-random value from the generator. If the rotate parameter is true, then
   * the random number is rotated such that the midpoint of the first bin will fall at zero. e.g. If
   * there are eight bins, and the random number falls in the first bin, .0625 is subtracted from
   * the number. A modulus of 1 is then applied so that values will remain in the interval zero to
   * 1. This way, the values can be post-multiplied by tau=2*pi to get an angle.
   */
  @Override
  public Number getNext() {
    double val = emp.nextDouble();
    return rotate ? (1 + (val - inc)) % 1d : val;
  }

  /**
   * Sets whether probability values should be rotated so that the midpoint of the first bin falls
   * on zero.
   *
   * @param rotate - indicates whether probability values should be rotated.
   */
  public void setRotate(boolean rotate) {
    this.rotate = rotate;
  }

  /**
   * Sets the weights (and number) of the bins
   *
   * @param weights - the pdf to be used to weight the bins
   */
  public void setWeights(double[] weights) {
    this.weights = weights;
    inc = 1d / (weights.length * 2d);
    emp.setState(weights, Empirical.LINEAR_INTERPOLATION);
  }
}
  @Override
  protected DoubleMatrix1D getGlobalStart(
      final double forward,
      final double[] strikes,
      final double expiry,
      final double[] impliedVols) {
    final RandomEngine random = getRandom();
    final DoubleMatrix1D fitP = getPolynomialFit(forward, strikes, impliedVols);

    final double a = fitP.getEntry(0);
    final double b = fitP.getEntry(1);
    final double c = fitP.getEntry(2);

    if (Math.abs(b) < 1e-3 && Math.abs(c) < 1e-3) { // almost flat smile
      final double theta = Math.PI / 2 - 0.01;
      return new DoubleMatrix1D(a, 0.01, theta, theta);
    }
    final double theta = Math.PI / 2 * random.nextDouble();
    return new DoubleMatrix1D(
        a * (0.8 + 0.4 * random.nextDouble()), a * 0.5 * random.nextDouble(), theta, theta);
  }
  @Test
  public void test() {
    final int nSamples = 10;
    final List<DoublesPair> points = new ArrayList<>(nSamples);
    final DoubleMatrix1D x = new DoubleMatrix1D(nSamples);
    for (int i = 0; i < nSamples; i++) {
      final double t = RANDOM.nextDouble() * 20.0;
      final double k = RANDOM.nextDouble() * 0.15;
      points.add(DoublesPair.of(t, k));
      x.getData()[i] = RANDOM.nextDouble();
    }

    final DiscreteVolatilityFunctionProvider pro = new DiscreteVolatilityFunctionProviderDirect();
    final DiscreteVolatilityFunction func = pro.from(points);
    final DoubleMatrix1D y = func.evaluate(x);
    AssertMatrix.assertEqualsVectors(x, y, 0.0);
    final DoubleMatrix2D jac = func.calculateJacobian(x);
    AssertMatrix.assertEqualsMatrix(new IdentityMatrix(nSamples), jac, 0.0);

    assertEquals(nSamples, func.getLengthOfDomain());
    assertEquals(nSamples, func.getLengthOfRange());
  }
Esempio n. 12
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 @Test
 public void testNormal() {
   final ProbabilityDistribution<Double> highDOF = new StudentTDistribution(1000000, ENGINE);
   final ProbabilityDistribution<Double> normal = new NormalDistribution(0, 1, ENGINE);
   final double eps = 1e-4;
   double x;
   for (int i = 0; i < 100; i++) {
     x = RANDOM.nextDouble();
     assertEquals(highDOF.getCDF(x), normal.getCDF(x), eps);
     assertEquals(highDOF.getPDF(x), normal.getPDF(x), eps);
     assertEquals(highDOF.getInverseCDF(x), normal.getInverseCDF(x), eps);
   }
 }
 @SuppressWarnings("unchecked")
 @Test
 public void testReturnsWithZeroesInSeries() {
   final int n = 20;
   final long[] times = new long[n];
   final double[] data = new double[n];
   final double[] returns = new double[n - 3];
   double random;
   for (int i = 0; i < n - 2; i++) {
     times[i] = i;
     random = RANDOM.nextDouble();
     data[i] = random;
     if (i > 0) {
       returns[i - 1] = Math.log(random / data[i - 1]);
     }
   }
   times[n - 2] = n - 2;
   data[n - 2] = 0;
   times[n - 1] = n - 1;
   data[n - 1] = RANDOM.nextDouble();
   final DoubleTimeSeries<Long> priceTS = new FastArrayLongDoubleTimeSeries(ENCODING, times, data);
   final DoubleTimeSeries<Long> returnTS =
       new FastArrayLongDoubleTimeSeries(ENCODING, Arrays.copyOfRange(times, 1, n - 2), returns);
   final TimeSeriesReturnCalculator strict =
       new ContinuouslyCompoundedTimeSeriesReturnCalculator(CalculationMode.STRICT);
   final DoubleTimeSeries<Long>[] tsArray = new DoubleTimeSeries[] {priceTS};
   try {
     strict.evaluate(tsArray);
     Assert.fail();
   } catch (final TimeSeriesException e) {
     // Expected
   }
   final TimeSeriesReturnCalculator lenient =
       new ContinuouslyCompoundedTimeSeriesReturnCalculator(CalculationMode.LENIENT);
   assertTrue(lenient.evaluate(tsArray).equals(returnTS));
 }
 @Test
 public void testReturnsWithoutDividends() {
   final int n = 20;
   final long[] times = new long[n];
   final double[] data = new double[n];
   final double[] returns = new double[n - 1];
   double random;
   for (int i = 0; i < n; i++) {
     times[i] = i;
     random = RANDOM.nextDouble();
     data[i] = random;
     if (i > 0) {
       returns[i - 1] = Math.log(random / data[i - 1]);
     }
   }
   final DoubleTimeSeries<Long> priceTS = new FastArrayLongDoubleTimeSeries(ENCODING, times, data);
   final DoubleTimeSeries<Long> returnTS =
       new FastArrayLongDoubleTimeSeries(ENCODING, Arrays.copyOfRange(times, 1, n), returns);
   assertTrue(CALCULATOR.evaluate(new DoubleTimeSeries[] {priceTS}).equals(returnTS));
 }