DT/Histogram.cpp at master · tgbudd/DT · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
#include "Histogram.h"
#include "utilities.h"


template<typename T>
Histogram<T>::Histogram(T min, T max, int bins, bool calculateaverage) :
	bins_(bins),
	min_(min),
	max_(max),
	measurements_(0),
	total_(0.0),
	total_squared_(0.0),
	below_min_(0),
	calculateaverage_(calculateaverage)
{
	histogram_.resize(bins_,0);
}

template<typename T>
T Histogram<T>::GetMin() const
{
	return min_;
}

template<typename T>
T Histogram<T>::GetMax() const
{
	return max_;
}

template<typename T>
int Histogram<T>::GetBins() const
{
	return bins_;
}

template<typename T>
int Histogram<T>::Bin(T x) const
{
	return static_cast<int>(((x - min_)*bins_)/(max_-min_));
}

template<typename T>
bool Histogram<T>::Insert(T x)
{
	if( calculateaverage_ )
	{
		total_ += static_cast<double>(x);
		total_squared_ += static_cast<double>(x)*static_cast<double>(x);
	}
	measurements_++;

	int bin = Bin(x);
	if( bin < 0 )
	{
		below_min_++;
	} else if( bin < bins_ )
	{
		histogram_[bin]++;
		return true;
	}
	return false;
}

template<typename T>
int Histogram<T>::Cumulative(T value) const
{
	// return the number of measurements in the bins up to but excluding the bin containing value
	return CumulativeAtBin(Bin(value));
}

template<typename T>
int Histogram<T>::CumulativeAtBin(int bin) const
{
	// return the number of measurements in the bins up to but excluding bin
	if( bin > bins_ )
	{
		bin = bins_;
	}
	int cumul = below_min_;
	for(int i=0;i<bin;++i)
	{
		cumul += histogram_[i];
	}
	return cumul;
}

template<typename T>
std::vector<int> Histogram<T>::CumulToBin(const std::vector<int> & cumul) const
{
	// Returns a vector bins, where bins[i] is the bin at which the CumulativeAtBin(bins[i]) first exceeds cumul[i].
	// Assuming cumul is sorted!
	std::vector<int> bins;
	bins.reserve(cumul.size());
	int num = below_min_;
	int current_bin = 0;
	for(int i=0,endi=cumul.size();i<endi;++i)
	{
		while( current_bin < bins_ && num < cumul[i] )
		{
			num += histogram_[current_bin];
			current_bin++;
		}
		bins.push_back(current_bin);
	}
	return bins;
}

template<typename T>
void Histogram<T>::Resize(int bins)
{
	bins_ = bins;
	histogram_.resize(bins_,0);
}

template<typename T>
void Histogram<T>::Reset()
{
	std::fill(histogram_.begin(),histogram_.end(),0);
	measurements_ = 0;
	total_ = 0.0;
	total_squared_ = 0.0;
	below_min_ = 0;
}

template<typename T>
void Histogram<T>::PrintTo(std::ostream & stream) const
{
	stream << "{min -> " << min_;
	stream << ", max -> " << max_;
	stream << ", bins -> " << bins_;
	stream << ", measurements -> " << measurements_;
	stream << ", belowmin -> " << below_min_;
	if( calculateaverage_ )
	{
		stream << ", average -> " << total_/measurements_;
		stream << ", variance -> " << (total_squared_ - total_*total_/measurements_)/measurements_;
	}
	stream << ", histogram -> ";
	PrintToStream( stream, histogram_.begin(), histogram_.end() );
	stream << "}";
}

template<typename T>
ExtendableHistogram<T>::ExtendableHistogram(T min, T delta) :
	Histogram<T>(min,min,0),
	delta_(delta)
{

}

template<typename T>
bool ExtendableHistogram<T>::Insert(T x)
{
	if( x >= this->max_ )
	{
		int bin = static_cast<int>((x - this->min_)/this->delta_);
		this->Resize(bin+1);
		this->max_ = (bin+1) * delta_;
	}
	return Histogram<T>::Insert(x);
}

// Explicitly instantiate frequently used templates.
template class Histogram<double>;
template class Histogram<float>;
template class Histogram<int>;
template class ExtendableHistogram<int>;
template class ExtendableHistogram<double>;