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// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#ifndef STORAGE_LEVELDB_UTIL_HISTOGRAM_H_
#define STORAGE_LEVELDB_UTIL_HISTOGRAM_H_
#include <string>
namespace leveldb {
class Histogram {
public:
Histogram() { }
~Histogram() { }
void Clear();
void Add(double value);
void Merge(const Histogram& other);
std::string ToString() const;
private:
double min_;
double max_;
double num_;
double sum_;
double sum_squares_;
enum { kNumBuckets = 154 };
static const double kBucketLimit[kNumBuckets];
double buckets_[kNumBuckets];
double Median() const;
double Percentile(double p) const;
double Average() const;
double StandardDeviation() const;
};
} // namespace leveldb
#endif // STORAGE_LEVELDB_UTIL_HISTOGRAM_H_
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