1
|
|
|
<?php |
2
|
|
|
|
3
|
|
|
declare (strict_types = 1); |
4
|
|
|
|
5
|
|
|
namespace Phpml\Metric; |
6
|
|
|
|
7
|
|
|
class ClassificationReport |
8
|
|
|
{ |
9
|
|
|
/** |
10
|
|
|
* @var array |
11
|
|
|
*/ |
12
|
|
|
private $precision = []; |
13
|
|
|
|
14
|
|
|
/** |
15
|
|
|
* @var array |
16
|
|
|
*/ |
17
|
|
|
private $recall = []; |
18
|
|
|
|
19
|
|
|
/** |
20
|
|
|
* @var array |
21
|
|
|
*/ |
22
|
|
|
private $f1score = []; |
23
|
|
|
|
24
|
|
|
/** |
25
|
|
|
* @var array |
26
|
|
|
*/ |
27
|
|
|
private $support = []; |
28
|
|
|
|
29
|
|
|
/** |
30
|
|
|
* @var array |
31
|
|
|
*/ |
32
|
|
|
private $average = []; |
33
|
|
|
|
34
|
|
|
/** |
35
|
|
|
* @param array $actualLabels |
36
|
|
|
* @param array $predictedLabels |
37
|
|
|
*/ |
38
|
|
|
public function __construct(array $actualLabels, array $predictedLabels) |
39
|
|
|
{ |
40
|
|
|
$truePositive = $falsePositive = $falseNegative = $this->support = self::getLabelIndexedArray($actualLabels); |
41
|
|
|
|
42
|
|
|
foreach ($actualLabels as $index => $actual) { |
43
|
|
|
$predicted = $predictedLabels[$index]; |
44
|
|
|
++$this->support[$actual]; |
45
|
|
|
|
46
|
|
|
if ($actual === $predicted) { |
47
|
|
|
++$truePositive[$actual]; |
48
|
|
|
} else { |
49
|
|
|
++$falsePositive[$predicted]; |
50
|
|
|
++$falseNegative[$actual]; |
51
|
|
|
} |
52
|
|
|
} |
53
|
|
|
|
54
|
|
|
$this->computeMetrics($truePositive, $falsePositive, $falseNegative); |
55
|
|
|
$this->computeAverage(); |
56
|
|
|
} |
57
|
|
|
|
58
|
|
|
/** |
59
|
|
|
* @return array |
60
|
|
|
*/ |
61
|
|
|
public function getPrecision() |
62
|
|
|
{ |
63
|
|
|
return $this->precision; |
64
|
|
|
} |
65
|
|
|
|
66
|
|
|
/** |
67
|
|
|
* @return array |
68
|
|
|
*/ |
69
|
|
|
public function getRecall() |
70
|
|
|
{ |
71
|
|
|
return $this->recall; |
72
|
|
|
} |
73
|
|
|
|
74
|
|
|
/** |
75
|
|
|
* @return array |
76
|
|
|
*/ |
77
|
|
|
public function getF1score() |
78
|
|
|
{ |
79
|
|
|
return $this->f1score; |
80
|
|
|
} |
81
|
|
|
|
82
|
|
|
/** |
83
|
|
|
* @return array |
84
|
|
|
*/ |
85
|
|
|
public function getSupport() |
86
|
|
|
{ |
87
|
|
|
return $this->support; |
88
|
|
|
} |
89
|
|
|
|
90
|
|
|
/** |
91
|
|
|
* @return array |
92
|
|
|
*/ |
93
|
|
|
public function getAverage() |
94
|
|
|
{ |
95
|
|
|
return $this->average; |
96
|
|
|
} |
97
|
|
|
|
98
|
|
|
/** |
99
|
|
|
* @param array $truePositive |
100
|
|
|
* @param array $falsePositive |
101
|
|
|
* @param array $falseNegative |
102
|
|
|
*/ |
103
|
|
|
private function computeMetrics(array $truePositive, array $falsePositive, array $falseNegative) |
104
|
|
|
{ |
105
|
|
|
foreach ($truePositive as $label => $tp) { |
106
|
|
|
$this->precision[$label] = $tp / ($tp + $falsePositive[$label]); |
107
|
|
|
$this->recall[$label] = $tp / ($tp + $falseNegative[$label]); |
108
|
|
|
$this->f1score[$label] = $this->computeF1Score((float) $this->precision[$label], (float) $this->recall[$label]); |
109
|
|
|
} |
110
|
|
|
} |
111
|
|
|
|
112
|
|
|
private function computeAverage() |
113
|
|
|
{ |
114
|
|
|
foreach (['precision', 'recall', 'f1score'] as $metric) { |
115
|
|
|
$values = array_filter($this->$metric); |
116
|
|
|
$this->average[$metric] = array_sum($values) / count($values); |
117
|
|
|
} |
118
|
|
|
} |
119
|
|
|
|
120
|
|
|
/** |
121
|
|
|
* @param float $precision |
122
|
|
|
* @param float $recall |
123
|
|
|
* |
124
|
|
|
* @return float |
125
|
|
|
*/ |
126
|
|
|
private function computeF1Score(float $precision, float $recall): float |
127
|
|
|
{ |
128
|
|
|
if (0 == ($divider = $precision + $recall)) { |
129
|
|
|
return 0.0; |
130
|
|
|
} |
131
|
|
|
|
132
|
|
|
return 2.0 * (($precision * $recall) / ($divider)); |
133
|
|
|
} |
134
|
|
|
|
135
|
|
|
/** |
136
|
|
|
* @param array $labels |
137
|
|
|
* |
138
|
|
|
* @return array |
139
|
|
|
*/ |
140
|
|
|
private static function getLabelIndexedArray(array $labels): array |
141
|
|
|
{ |
142
|
|
|
$labels = array_values(array_unique($labels)); |
143
|
|
|
sort($labels); |
144
|
|
|
$labels = array_combine($labels, array_fill(0, count($labels), 0)); |
145
|
|
|
|
146
|
|
|
return $labels; |
147
|
|
|
} |
148
|
|
|
} |
149
|
|
|
|