moving_average.hpp

// Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
//
// 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.
 
#ifndef LIBSTATISTICS_COLLECTOR__MOVING_AVERAGE_STATISTICS__MOVING_AVERAGE_HPP_
#define LIBSTATISTICS_COLLECTOR__MOVING_AVERAGE_STATISTICS__MOVING_AVERAGE_HPP_
 
#include <cmath>
 
#include <algorithm>
#include <limits>
#include <mutex>
#include <numeric>
#include <type_traits>
 
#include "types.hpp"
 
#include "libstatistics_collector/visibility_control.hpp"
 
#include "rcpputils/thread_safety_annotations.hpp"
 
namespace libstatistics_collector
{
namespace moving_average_statistics
{
 
class MovingAverageStatistics
{
public:
  LIBSTATISTICS_COLLECTOR_PUBLIC
  MovingAverageStatistics() = default;
 
  LIBSTATISTICS_COLLECTOR_PUBLIC
  ~MovingAverageStatistics() = default;
 
  LIBSTATISTICS_COLLECTOR_PUBLIC
  double Average() const RCPPUTILS_TSA_REQUIRES(mutex_);
 
  LIBSTATISTICS_COLLECTOR_PUBLIC
  double Max() const RCPPUTILS_TSA_REQUIRES(mutex_);
 
  LIBSTATISTICS_COLLECTOR_PUBLIC
  double Min() const RCPPUTILS_TSA_REQUIRES(mutex_);
 
  LIBSTATISTICS_COLLECTOR_PUBLIC
  double StandardDeviation() const RCPPUTILS_TSA_REQUIRES(mutex_);
 
  LIBSTATISTICS_COLLECTOR_PUBLIC
  StatisticData GetStatistics() const;
 
  LIBSTATISTICS_COLLECTOR_PUBLIC
  void Reset();
 
  LIBSTATISTICS_COLLECTOR_PUBLIC
  virtual void AddMeasurement(const double item);
 
  LIBSTATISTICS_COLLECTOR_PUBLIC
  uint64_t GetCount() const;
 
private:
  mutable std::mutex mutex_;
  double average_ RCPPUTILS_TSA_GUARDED_BY(mutex_) = 0;
  double min_ RCPPUTILS_TSA_GUARDED_BY(mutex_) = std::numeric_limits<double>::max();
  double max_ RCPPUTILS_TSA_GUARDED_BY(mutex_) = std::numeric_limits<double>::min();
  double sum_of_square_diff_from_mean_ RCPPUTILS_TSA_GUARDED_BY(mutex_) = 0;
  uint64_t count_ RCPPUTILS_TSA_GUARDED_BY(mutex_) = 0;
};
 
}  // namespace moving_average_statistics
}  // namespace libstatistics_collector
 
#endif  // LIBSTATISTICS_COLLECTOR__MOVING_AVERAGE_STATISTICS__MOVING_AVERAGE_HPP_