/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You under the Apache License, Version 2.0
    * (the "License"); you may not use this file except in compliance with
    * the License.  You may obtain a copy of the License at
    *
    *      https://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  /*
   * This is not the original file distributed by the Apache Software Foundation
   * It has been modified by the Hipparchus project
   */
  
  package org.hipparchus.distribution.discrete;
  
  import static org.junit.Assert.assertEquals;
  
  import org.hipparchus.UnitTestUtils;
  import org.hipparchus.distribution.IntegerDistribution;
  import org.hipparchus.exception.MathIllegalArgumentException;
  import org.hipparchus.util.Precision;
  import org.junit.Assert;
  import org.junit.Test;
  
  /**
   * Test cases for HyperGeometriclDistribution.
   */
  public class HypergeometricDistributionTest extends IntegerDistributionAbstractTest {
  
      /**
       * Constructor to override default tolerance.
       */
      public HypergeometricDistributionTest() {
          setTolerance(1e-12);
      }
  
      //-------------- Implementations for abstract methods -----------------------
  
      /** Creates the default discrete distribution instance to use in tests. */
      @Override
      public IntegerDistribution makeDistribution() {
          return new HypergeometricDistribution(10, 5, 5);
      }
  
      /** Creates the default probability density test input values */
      @Override
      public int[] makeDensityTestPoints() {
          return new int[] {-1, 0, 1, 2, 3, 4, 5, 10};
      }
  
      /**
       * Creates the default probability density test expected values
       * Reference values are from R, version 2.15.3.
       */
      @Override
      public double[] makeDensityTestValues() {
          return new double[] {0d, 0.00396825396825, 0.0992063492063, 0.396825396825, 0.396825396825,
              0.0992063492063, 0.00396825396825, 0d};
      }
  
      /**
       * Creates the default probability log density test expected values
       * Reference values are from R, version 2.14.1.
       */
      @Override
      public double[] makeLogDensityTestValues() {
          //-Inf  -Inf
          return new double[] {Double.NEGATIVE_INFINITY, -5.52942908751142, -2.31055326264322, -0.924258901523332,
                  -0.924258901523332, -2.31055326264322, -5.52942908751142, Double.NEGATIVE_INFINITY};
      }
  
      /** Creates the default cumulative probability density test input values */
      @Override
      public int[] makeCumulativeTestPoints() {
          return makeDensityTestPoints();
      }
  
      /**
       * Creates the default cumulative probability density test expected values
       * Reference values are from R, version 2.15.3.
       */
      @Override
      public double[] makeCumulativeTestValues() {
          return new double[] {0d, 0.00396825396825, 0.103174603175, .5, 0.896825396825, 0.996031746032,
                  1, 1};
      }
  
      /** Creates the default inverse cumulative probability test input values */
      @Override
      public double[] makeInverseCumulativeTestPoints() {
         return new double[] {0d, 0.001d, 0.010d, 0.025d, 0.050d, 0.100d, 0.999d,
                 0.990d, 0.975d, 0.950d, 0.900d, 1d};
     }
 
     /** Creates the default inverse cumulative probability density test expected values */
     @Override
     public int[] makeInverseCumulativeTestValues() {
         return new int[] {0, 0, 1, 1, 1, 1, 5, 4, 4, 4, 4, 5};
     }
 
     //-------------------- Additional test cases ------------------------------
 
     /** Verify that if there are no failures, mass is concentrated on sampleSize */
     @Test
     public void testDegenerateNoFailures() {
         HypergeometricDistribution dist = new HypergeometricDistribution(5,5,3);
         setDistribution(dist);
         setCumulativeTestPoints(new int[] {-1, 0, 1, 3, 10 });
         setCumulativeTestValues(new double[] {0d, 0d, 0d, 1d, 1d});
         setDensityTestPoints(new int[] {-1, 0, 1, 3, 10});
         setDensityTestValues(new double[] {0d, 0d, 0d, 1d, 0d});
         setInverseCumulativeTestPoints(new double[] {0.1d, 0.5d});
         setInverseCumulativeTestValues(new int[] {3, 3});
         verifyDensities();
         verifyCumulativeProbabilities();
         verifyInverseCumulativeProbabilities();
         Assert.assertEquals(dist.getSupportLowerBound(), 3);
         Assert.assertEquals(dist.getSupportUpperBound(), 3);
     }
 
     /** Verify that if there are no successes, mass is concentrated on 0 */
     @Test
     public void testDegenerateNoSuccesses() {
         HypergeometricDistribution dist = new HypergeometricDistribution(5,0,3);
         setDistribution(dist);
         setCumulativeTestPoints(new int[] {-1, 0, 1, 3, 10 });
         setCumulativeTestValues(new double[] {0d, 1d, 1d, 1d, 1d});
         setDensityTestPoints(new int[] {-1, 0, 1, 3, 10});
         setDensityTestValues(new double[] {0d, 1d, 0d, 0d, 0d});
         setInverseCumulativeTestPoints(new double[] {0.1d, 0.5d});
         setInverseCumulativeTestValues(new int[] {0, 0});
         verifyDensities();
         verifyCumulativeProbabilities();
         verifyInverseCumulativeProbabilities();
         Assert.assertEquals(dist.getSupportLowerBound(), 0);
         Assert.assertEquals(dist.getSupportUpperBound(), 0);
     }
 
     /** Verify that if sampleSize = populationSize, mass is concentrated on numberOfSuccesses */
     @Test
     public void testDegenerateFullSample() {
         HypergeometricDistribution dist = new HypergeometricDistribution(5,3,5);
         setDistribution(dist);
         setCumulativeTestPoints(new int[] {-1, 0, 1, 3, 10 });
         setCumulativeTestValues(new double[] {0d, 0d, 0d, 1d, 1d});
         setDensityTestPoints(new int[] {-1, 0, 1, 3, 10});
         setDensityTestValues(new double[] {0d, 0d, 0d, 1d, 0d});
         setInverseCumulativeTestPoints(new double[] {0.1d, 0.5d});
         setInverseCumulativeTestValues(new int[] {3, 3});
         verifyDensities();
         verifyCumulativeProbabilities();
         verifyInverseCumulativeProbabilities();
         Assert.assertEquals(dist.getSupportLowerBound(), 3);
         Assert.assertEquals(dist.getSupportUpperBound(), 3);
     }
 
     @Test
     public void testPreconditions() {
         try {
             new HypergeometricDistribution(0, 3, 5);
             Assert.fail("negative population size. MathIllegalArgumentException expected");
         } catch(MathIllegalArgumentException ex) {
             // Expected.
         }
         try {
             new HypergeometricDistribution(5, -1, 5);
             Assert.fail("negative number of successes. MathIllegalArgumentException expected");
         } catch(MathIllegalArgumentException ex) {
             // Expected.
         }
         try {
             new HypergeometricDistribution(5, 3, -1);
             Assert.fail("negative sample size. MathIllegalArgumentException expected");
         } catch(MathIllegalArgumentException ex) {
             // Expected.
         }
         try {
             new HypergeometricDistribution(5, 6, 5);
             Assert.fail("numberOfSuccesses > populationSize. MathIllegalArgumentException expected");
         } catch(MathIllegalArgumentException ex) {
             // Expected.
         }
         try {
             new HypergeometricDistribution(5, 3, 6);
             Assert.fail("sampleSize > populationSize. MathIllegalArgumentException expected");
         } catch(MathIllegalArgumentException ex) {
             // Expected.
         }
     }
 
     @Test
     public void testAccessors() {
         HypergeometricDistribution dist = new HypergeometricDistribution(5, 3, 4);
         Assert.assertEquals(5, dist.getPopulationSize());
         Assert.assertEquals(3, dist.getNumberOfSuccesses());
         Assert.assertEquals(4, dist.getSampleSize());
     }
 
     @Test
     public void testLargeValues() {
         int populationSize = 3456;
         int sampleSize = 789;
         int numberOfSucceses = 101;
         double[][] data = {
             {0.0, 2.75646034603961e-12, 2.75646034603961e-12, 1.0},
             {1.0, 8.55705370142386e-11, 8.83269973602783e-11, 0.999999999997244},
             {2.0, 1.31288129219665e-9, 1.40120828955693e-9, 0.999999999911673},
             {3.0, 1.32724172984193e-8, 1.46736255879763e-8, 0.999999998598792},
             {4.0, 9.94501711734089e-8, 1.14123796761385e-7, 0.999999985326375},
             {5.0, 5.89080768883643e-7, 7.03204565645028e-7, 0.999999885876203},
             {20.0, 0.0760051397707708, 0.27349758476299, 0.802507555007781},
             {21.0, 0.087144222047629, 0.360641806810619, 0.72650241523701},
             {22.0, 0.0940378846881819, 0.454679691498801, 0.639358193189381},
             {23.0, 0.0956897500614809, 0.550369441560282, 0.545320308501199},
             {24.0, 0.0919766921922999, 0.642346133752582, 0.449630558439718},
             {25.0, 0.083641637261095, 0.725987771013677, 0.357653866247418},
             {96.0, 5.93849188852098e-57, 1.0, 6.01900244560712e-57},
             {97.0, 7.96593036832547e-59, 1.0, 8.05105570861321e-59},
             {98.0, 8.44582921934367e-61, 1.0, 8.5125340287733e-61},
             {99.0, 6.63604297068222e-63, 1.0, 6.670480942963e-63},
             {100.0, 3.43501099007557e-65, 1.0, 3.4437972280786e-65},
             {101.0, 8.78623800302957e-68, 1.0, 8.78623800302957e-68},
         };
 
         testHypergeometricDistributionProbabilities(populationSize, sampleSize, numberOfSucceses, data);
     }
 
     private void testHypergeometricDistributionProbabilities(int populationSize, int sampleSize, int numberOfSucceses, double[][] data) {
         HypergeometricDistribution dist = new HypergeometricDistribution(populationSize, numberOfSucceses, sampleSize);
         for (int i = 0; i < data.length; ++i) {
             int x = (int)data[i][0];
             double pmf = data[i][1];
             double actualPmf = dist.probability(x);
             UnitTestUtils.assertRelativelyEquals("Expected equals for <"+x+"> pmf",pmf, actualPmf, 1.0e-9);
 
             double cdf = data[i][2];
             double actualCdf = dist.cumulativeProbability(x);
             UnitTestUtils.assertRelativelyEquals("Expected equals for <"+x+"> cdf",cdf, actualCdf, 1.0e-9);
 
             double cdf1 = data[i][3];
             double actualCdf1 = dist.upperCumulativeProbability(x);
             UnitTestUtils.assertRelativelyEquals("Expected equals for <"+x+"> cdf1",cdf1, actualCdf1, 1.0e-9);
         }
     }
 
     @Test
     public void testMoreLargeValues() {
         int populationSize = 26896;
         int sampleSize = 895;
         int numberOfSucceses = 55;
         double[][] data = {
             {0.0, 0.155168304750504, 0.155168304750504, 1.0},
             {1.0, 0.29437545000746, 0.449543754757964, 0.844831695249496},
             {2.0, 0.273841321577003, 0.723385076334967, 0.550456245242036},
             {3.0, 0.166488572570786, 0.889873648905753, 0.276614923665033},
             {4.0, 0.0743969744713231, 0.964270623377076, 0.110126351094247},
             {5.0, 0.0260542785784855, 0.990324901955562, 0.0357293766229237},
             {20.0, 3.57101101678792e-16, 1.0, 3.78252101622096e-16},
             {21.0, 2.00551638598312e-17, 1.0, 2.11509999433041e-17},
             {22.0, 1.04317070180562e-18, 1.0, 1.09583608347287e-18},
             {23.0, 5.03153504903308e-20, 1.0, 5.266538166725e-20},
             {24.0, 2.2525984149695e-21, 1.0, 2.35003117691919e-21},
             {25.0, 9.3677424515947e-23, 1.0, 9.74327619496943e-23},
             {50.0, 9.83633962945521e-69, 1.0, 9.8677629437617e-69},
             {51.0, 3.13448949497553e-71, 1.0, 3.14233143064882e-71},
             {52.0, 7.82755221928122e-74, 1.0, 7.84193567329055e-74},
             {53.0, 1.43662126065532e-76, 1.0, 1.43834540093295e-76},
             {54.0, 1.72312692517348e-79, 1.0, 1.7241402776278e-79},
             {55.0, 1.01335245432581e-82, 1.0, 1.01335245432581e-82},
         };
         testHypergeometricDistributionProbabilities(populationSize, sampleSize, numberOfSucceses, data);
     }
 
     @Test
     public void testMoments() {
         final double tol = 1e-9;
         HypergeometricDistribution dist;
 
         dist = new HypergeometricDistribution(1500, 40, 100);
         Assert.assertEquals(dist.getNumericalMean(), 40d * 100d / 1500d, tol);
         Assert.assertEquals(dist.getNumericalVariance(), ( 100d * 40d * (1500d - 100d) * (1500d - 40d) ) / ( (1500d * 1500d * 1499d) ), tol);
 
         dist = new HypergeometricDistribution(3000, 55, 200);
         Assert.assertEquals(dist.getNumericalMean(), 55d * 200d / 3000d, tol);
         Assert.assertEquals(dist.getNumericalVariance(), ( 200d * 55d * (3000d - 200d) * (3000d - 55d) ) / ( (3000d * 3000d * 2999d) ), tol);
     }
 
     @Test
     public void testMath644() {
         int N = 14761461;  // population
         int m = 1035;      // successes in population
         int n = 1841;      // number of trials
 
         int k = 0;
         final HypergeometricDistribution dist = new HypergeometricDistribution(N, m, n);
 
         Assert.assertTrue(Precision.compareTo(1.0, dist.upperCumulativeProbability(k), 1) == 0);
         Assert.assertTrue(Precision.compareTo(dist.cumulativeProbability(k), 0.0, 1) > 0);
 
         // another way to calculate the upper cumulative probability
         double upper = 1.0 - dist.cumulativeProbability(k) + dist.probability(k);
         Assert.assertTrue(Precision.compareTo(1.0, upper, 1) == 0);
     }
 
     @Test
     public void testMath1356() {
         HypergeometricDistribution dist = new HypergeometricDistribution(11, 11, 1);
         assertEquals(1.0, dist.probability(1), 1e-6);
         assertEquals(0.0, dist.probability(0), 1e-6);
 
         dist = new HypergeometricDistribution(11, 11, 11);
         assertEquals(0.0, dist.probability(0), 1e-6);
         assertEquals(0.0, dist.probability(1), 1e-6);
         assertEquals(0.0, dist.probability(10), 1e-6);
         assertEquals(1.0, dist.probability(11), 1e-6);
     }
 }