public List getQuantiles()

in datafu-pig/src/main/java/datafu/pig/stats/StreamingQuantile.java [372:414]

• 38 lines of code
• 11 McCabe index (conditional complexity)

    public List<Double> getQuantiles()
    {
      List<Double> quantiles = new ArrayList<Double>();
      quantiles.add(min);
      
      if (buffer.get(0) != null) {
        Collections.sort(buffer.get(0));
      }
      if (buffer.get(1) != null) {
        Collections.sort(buffer.get(1));
      }
      
      int[] index = new int[buffer.size()];
      long S = 0;
      for (int i = 1; i <= numQuantiles - 2; i++) {
        long targetS = (long) Math.ceil(i * (totalElements / (numQuantiles - 1.0)));
        
        while (true) {
          double smallest = max;
          int minBufferId = -1;
          for (int j = 0; j < buffer.size(); j++) {
            if (buffer.get(j) != null && index[j] < buffer.get(j).size()) {
              if (!(smallest < buffer.get(j).get(index[j]))) {
                smallest = buffer.get(j).get(index[j]);
                minBufferId = j;
              }
            }
          }
          
          long incrementS = minBufferId <= 1 ? 1L : (0x1L << (minBufferId - 1));
          if (S + incrementS >= targetS) {
            quantiles.add(smallest);
            break;
          } else {
            index[minBufferId]++;
            S += incrementS;
          }
        }
      }
      
      quantiles.add(max);
      return quantiles;
    }