File indexing completed on 2024-04-06 12:01:12
0001 #include "CommonTools/Statistics/interface/Accumulator.h"
0002 #include <ostream>
0003
0004 Accumulator::Accumulator() : sum_(0.), sumOfSquares_(0.), weightedSum_(0.), sumOfWeights_(0.), n_(0) {}
0005
0006 void Accumulator::addEntry(double value, double weight) {
0007 sum_ += value;
0008 sumOfSquares_ += (value * value);
0009 weightedSum_ += value * weight;
0010 sumOfWeights_ += weight;
0011 ++n_;
0012 }
0013
0014 double Accumulator::mean() const { return sum_ / n_; }
0015
0016 double Accumulator::variance() const {
0017 double numerator = sumOfSquares_ - sum_ * mean();
0018 unsigned long denominator = n_ - 1;
0019 return numerator / denominator;
0020 }
0021
0022 double Accumulator::weightedMean() const { return weightedSum_ / sumOfWeights_; }
0023
0024 std::ostream& operator<<(std::ostream& os, const Accumulator& stat) {
0025 os << "entries: " << stat.nEntries();
0026 if (stat.nEntries() > 0) {
0027 os << " Mean: " << stat.mean();
0028 }
0029 if (stat.nEntries() > 1) {
0030 os << " Sigma: " << stat.sigma();
0031 }
0032 return os;
0033 }
