| // Copyright 2020 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "base/power_monitor/moving_average.h" |
| |
| #include <algorithm> |
| #include <limits> |
| |
| #include "base/check_op.h" |
| |
| namespace { |
| constexpr int kIntMax = std::numeric_limits<int>::max(); |
| constexpr int64_t kInt64Max = std::numeric_limits<int64_t>::max(); |
| } // namespace |
| |
| namespace base { |
| |
| MovingAverage::MovingAverage(uint8_t window_size) |
| : window_size_(window_size), buffer_(window_size, 0) { |
| DCHECK_LE(kIntMax * window_size, kInt64Max); |
| } |
| |
| MovingAverage::~MovingAverage() = default; |
| |
| void MovingAverage::AddSample(int sample) { |
| sum_ -= buffer_[index_]; |
| buffer_[index_++] = sample; |
| sum_ += sample; |
| if (index_ == window_size_) { |
| full_ = true; |
| index_ = 0; |
| } |
| } |
| |
| int MovingAverage::GetAverageRoundedDown() const { |
| if (Size() == 0) |
| return 0; |
| return sum_ / Size(); |
| } |
| |
| int MovingAverage::GetAverageRoundedToClosest() const { |
| if (Size() == 0) |
| return 0; |
| return (sum_ + Size() / 2) / Size(); |
| } |
| |
| double MovingAverage::GetUnroundedAverage() const { |
| if (Size() == 0) |
| return 0; |
| return sum_ / static_cast<double>(Size()); |
| } |
| |
| void MovingAverage::Reset() { |
| std::fill(buffer_.begin(), buffer_.end(), 0); |
| sum_ = 0; |
| index_ = 0; |
| full_ = false; |
| } |
| |
| size_t MovingAverage::Size() const { |
| return full_ ? window_size_ : index_; |
| } |
| } // namespace base |