public double getPercentile()

in harness/src/main/java/org/apache/geode/perftest/yardstick/analysis/YardstickPercentileSensorParser.java [93:125]

• 25 lines of code
• 5 McCabe index (conditional complexity)

  public double getPercentile(int target) {
    if (target < 0 || target > 100) {
      throw new RuntimeException(
          "Percentile must be in the range (0, 100), invalid value: " + target);
    }
    double targetPercent = target / 100.0;
    normalizeBuckets();

    if (buckets.size() == 1) {
      return buckets.get(0).latencyBucket; // Just one bucket doesn't give us much info
    }

    SensorBucket[] bucketArray = buckets.toArray(new SensorBucket[buckets.size()]);

    double accumulator = 0;
    int i = -1;
    while (targetPercent - accumulator > 0.0001) {
      ++i;
      accumulator += bucketArray[i].bucketPercentage;
    }
    // Post-condition: accumulator >= targetPercent, i is index of last block added

    SensorBucket targetBucket = bucketArray[i];
    // If last bucket contains the target percentile, assume bucket size is same as previous bucket
    int bucketSize =
        (bucketArray.length > i + 1) ? bucketArray[i + 1].latencyBucket - targetBucket.latencyBucket
            : targetBucket.latencyBucket - bucketArray[i - 1].latencyBucket;

    double percentileLocationInTargetBucket =
        1.0 - ((accumulator - targetPercent) / targetBucket.bucketPercentage);

    return targetBucket.latencyBucket + bucketSize * percentileLocationInTargetBucket;
  }