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diff --git a/runtime/base/histogram.h b/runtime/base/histogram.h
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+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * 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 ART_SRC_BASE_HISTOGRAM_H_
+#define ART_SRC_BASE_HISTOGRAM_H_
+
+#include <vector>
+#include <string>
+
+#include "base/logging.h"
+#include "utils.h"
+
+namespace art {
+
+// Creates a data histogram  for a better understanding of statistical data.
+// Histogram analysis goes beyond simple mean and standard deviation to provide
+// percentiles values, describing where the $% of the input data lies.
+// Designed to be simple and used with timing logger in art.
+
+template <class Value> class Histogram {
+
+  const double kAdjust;
+  const Value kBucketWidth;
+  const size_t kInitialBucketCount;
+
+ public:
+  Histogram(std::string);
+  void AddValue(Value);
+  void CreateHistogram();
+  void Reset();
+  double Mean() const;
+  double Variance() const;
+  double Percentile(double) const;
+  void PrintConfidenceIntervals(std::ostream &, double) const;
+  void PrintBins(std::ostream &);
+
+  uint64_t SampleSize() const {
+    return sample_size_;
+  }
+
+  Value Sum() const {
+    return sum_;
+  }
+
+  Value Min() const {
+    return min_value_added_;
+  }
+
+  Value Max() const {
+    return max_value_added_;
+  }
+
+  const std::string &Name() const {
+    return name_;
+  }
+
+
+ private:
+  void BuildRanges();
+  void Initialize();
+  size_t FindBucket(Value);
+  void BucketiseValue(Value);
+  // Builds the cumulative distribution function from the frequency data.
+  // Must be called before using the percentile function.
+  void BuildCDF();
+  // Add more buckets to the histogram to fill in a new value that exceeded
+  // the max_read_value_.
+  void GrowBuckets(Value);
+  bool new_values_added_;
+  std::string name_;
+  // Number of samples placed in histogram.
+  uint64_t sample_size_;
+  // Width of the bucket range. The lower the value is the more accurate
+  // histogram percentiles are.
+  Value bucket_width_;
+  // Number of bucket to have in the histogram. this value will increase
+  // to accommodate for big values that don't fit in initial bucket ranges.
+  size_t bucket_count_;
+  // Represents the ranges of the histograms. Has SampleSize() + 1 elements
+  // e.g. 0,5,10,15 represents ranges 0-5, 5-10, 10-15
+  std::vector<Value> ranges_;
+  // How many occurrences of values fall within a corresponding range that is
+  // saved in the ranges_ vector.
+  std::vector<uint64_t> frequency_;
+  // Accumulative summation of frequencies.
+  // cumulative_freq_[i] = sum(cumulative_freq_[j] : 0 < j < i )
+  std::vector<uint64_t> cumulative_freq_;
+  // Accumulative summation of percentiles; which is the frequency / SampleSize
+  // cumulative_freq_[i] = sum(cumulative_freq_[j] : 0 < j < i )
+  std::vector<double> cumulative_perc_;
+  // Summation of all the elements inputed by the user.
+  Value sum_;
+  // Maximum value that can fit in the histogram, grows adaptively.
+  Value min_;
+  // Minimum value that can fit in the histogram. Fixed to zero for now.
+  Value max_;
+  // Summation of the values entered. Used to calculate variance.
+  Value sum_of_squares_;
+  // Maximum value entered in the histogram.
+  Value min_value_added_;
+  // Minimum value entered in the histogram.
+  Value max_value_added_;
+
+  DISALLOW_COPY_AND_ASSIGN(Histogram);
+};
+}
+
+#endif  // ART_SRC_BASE_HISTOGRAM_H_