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
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
|
package de.lmu.ifi.dbs.elki.utilities.datastructures.histogram;
/*
This file is part of ELKI:
Environment for Developing KDD-Applications Supported by Index-Structures
Copyright (C) 2015
Ludwig-Maximilians-Universität München
Lehr- und Forschungseinheit für Datenbanksysteme
ELKI Development Team
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* Abstract base class for histograms.
*
* Note that this is abstracted from the actual data storage, so it can be
* adapted for multiple use cases.
*
* @author Erich Schubert
*/
public abstract class AbstractStaticHistogram implements Histogram {
/**
* Array shift to account for negative indices.
*/
protected int offset = 0;
/**
* Size of array storage.
*/
protected int size;
/**
* Array 'base', i.e. the point of 0.0. Usually the minimum.
*/
protected double base;
/**
* To avoid introducing an extra bucket for the maximum value.
*/
protected double max;
/**
* Width of a bin.
*/
protected double binsize;
/**
* Histogram constructor
*
* @param bins Number of bins to use.
* @param min Minimum Value
* @param max Maximum Value
*/
public AbstractStaticHistogram(int bins, double min, double max) {
this.base = min;
this.max = max;
this.binsize = (max - min) / bins;
this.size = bins;
}
/**
* Compute the bin number. Has a special case for rounding max down to the
* last bin.
*
* @param coord Coordinate
* @return bin number
*/
protected int getBinNr(double coord) {
if (Double.isInfinite(coord) || Double.isNaN(coord)) {
throw new UnsupportedOperationException("Encountered non-finite value in Histogram: " + coord);
}
if (coord == max) {
// System.err.println("Triggered special case: "+ (Math.floor((coord -
// base) / binsize) + offset) + " vs. " + (size - 1));
return size - 1;
}
return (int) Math.floor((coord - base) / binsize) + offset;
}
/**
* Compute the size to grow to.
*
* @param current Current size
* @param requiredSize Required size
* @return Size to allocate
*/
protected static int growSize(int current, int requiredSize) {
// Double until 64, then increase by 50% each time.
int newCapacity = ((current < 64) ? ((current + 1) << 1) : ((current >> 1) * 3));
// overflow?
if (newCapacity < 0) {
throw new OutOfMemoryError();
}
if (requiredSize > newCapacity) {
newCapacity = requiredSize;
}
return requiredSize;
}
/**
* Get the number of bins actually in use.
*
* @return number of bins
*/
@Override
public int getNumBins() {
return size;
}
/**
* Get the size (width) of a bin.
*
* @return bin size
*/
@Override
public double getBinsize() {
return binsize;
}
/**
* Get minimum (covered by bins, not data!)
*
* @return minimum
*/
@Override
public double getCoverMinimum() {
return base - offset * binsize;
}
/**
* Get maximum (covered by bins, not data!)
*
* @return maximum
*/
@Override
public double getCoverMaximum() {
return base + (size - offset) * binsize;
}
/**
* Get an iterator over all histogram bins.
*
* @return Iterator
*/
@Override
public abstract Iter iter();
/**
* Iterator class to iterate over all bins.
*
* @author Erich Schubert
*
* @apiviz.exclude
*/
public abstract class Iter implements Histogram.Iter {
/**
* Current bin number
*/
int bin = 0;
@Override
public double getCenter() {
return base + (bin + 0.5 - offset) * binsize;
}
@Override
public double getLeft() {
return base + (bin - offset) * binsize;
}
@Override
public double getRight() {
return base + (bin + 1 - offset) * binsize;
}
@Override
public boolean valid() {
return bin >= 0 && bin < size;
}
@Override
public Iter advance() {
bin++;
return this;
}
@Override
public int getOffset() {
return bin;
}
@Override
public Iter advance(int count) {
bin += count;
return this;
}
@Override
public Iter retract() {
bin--;
return this;
}
@Override
public Iter seek(int off) {
bin = off;
return this;
}
}
}
|
