content: /*
   * Copyright (C) 2011 Clearspring Technologies, Inc.
   *
   * Licensed 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
   *
   * http://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.
   */
  
  package com.clearspring.experimental.stream.cardinality;
  
  import com.clearspring.analytics.stream.cardinality.TestICardinality;
  
  import org.junit.Test;
  import org.junit.Ignore;
  import static org.junit.Assert.assertTrue;
  
  
  public class TestHyperBitBit {
      // This test are "in progress" until HyperBitBit has better known error bounds
      // Right now they will no fail ever (@ignore)
  
  
      @Test
      @Ignore
      public void testSimpleHighCardinality() {
          int size = 10000000;
          int max_repetitions = 5;
          double errors_mean = 0;
          for (int repetitions = 0; repetitions < max_repetitions; ++repetitions) {
              long start = System.currentTimeMillis();
              HyperBitBit hyperBitBit = new HyperBitBit();
  
              for (int i = 0; i < size; i++) {
                  hyperBitBit.offer(TestICardinality.streamElement(i));
              }
              System.out.println("time: " + (System.currentTimeMillis() - start));
              long estimate = hyperBitBit.cardinality();
              double err = Math.abs(estimate - size) / (double) size;
              errors_mean += (err/max_repetitions);
              System.out.println(err);
          }
          System.out.println("This value should be less than 0.25: " + errors_mean);
          assertTrue(errors_mean < 0.1);
  
      }
  
      @Test
      @Ignore
      public void testMultipleOrderedHighCardinality() {
          int size = 10000000;
  
          long start = System.currentTimeMillis();
  
          HyperBitBit hyperBitBit = new HyperBitBit();
  
          for (int i = 0; i < size; i++) {
              hyperBitBit.offer(i);
              hyperBitBit.offer(i);
              hyperBitBit.offer(i);
              hyperBitBit.offer(i);
          }
  
          System.out.println("time: " + (System.currentTimeMillis() - start));
          long estimate = hyperBitBit.cardinality();
          double err = Math.abs(estimate - size) / (double) size;
          System.out.println(err);
          System.out.println("This value should be less than 0.2: " + err);
          assertTrue(err < 0.1);
      }
  
      @Test
      @Ignore
      public void testMultipleUnorderedHighCardinality() {
          int size = 10000000;
  
          long start = System.currentTimeMillis();
  
          HyperBitBit hyperBitBit = new HyperBitBit();
  
          for (int i = 0; i < size; i++) {
              hyperBitBit.offer(i);
          }
  
          for (int i = 0; i < size; i++) {
              hyperBitBit.offer(i);
          }
  
          for (int i = 0; i < size; i++) {
              hyperBitBit.offer(i);
          }
  
          System.out.println("time: " + (System.currentTimeMillis() - start));
          long estimate = hyperBitBit.cardinality();
          double err = Math.abs(estimate - size) / (double) size;
          System.out.println(err);
  
          System.out.println("This value should be less than 0.2: " + err);
          assertTrue(err < 0.1);
      }
  }
  