|  | /* | 
|  | *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved. | 
|  | * | 
|  | *  Use of this source code is governed by a BSD-style license | 
|  | *  that can be found in the LICENSE file in the root of the source | 
|  | *  tree. An additional intellectual property rights grant can be found | 
|  | *  in the file PATENTS.  All contributing project authors may | 
|  | *  be found in the AUTHORS file in the root of the source tree. | 
|  | */ | 
|  | #ifndef WEBRTC_TEST_STATISTICS_H_ | 
|  | #define WEBRTC_TEST_STATISTICS_H_ | 
|  |  | 
|  | #include "webrtc/typedefs.h" | 
|  |  | 
|  | namespace webrtc { | 
|  | namespace test { | 
|  |  | 
|  | class Statistics { | 
|  | public: | 
|  | Statistics(); | 
|  |  | 
|  | void AddSample(double sample); | 
|  |  | 
|  | double Mean() const; | 
|  | double Variance() const; | 
|  | double StandardDeviation() const; | 
|  |  | 
|  | private: | 
|  | double sum_; | 
|  | double sum_squared_; | 
|  | uint64_t count_; | 
|  | }; | 
|  | }  // namespace test | 
|  | }  // namespace webrtc | 
|  |  | 
|  | #endif  // WEBRTC_TEST_STATISTICS_H_ |