1 | <?php |
||
2 | |||
3 | declare(strict_types=1); |
||
4 | |||
5 | namespace Phpml\Metric; |
||
6 | |||
7 | class ConfusionMatrix |
||
8 | { |
||
9 | public static function compute(array $actualLabels, array $predictedLabels, array $labels = []): array |
||
10 | { |
||
11 | $labels = count($labels) === 0 ? self::getUniqueLabels($actualLabels) : array_flip($labels); |
||
12 | $matrix = self::generateMatrixWithZeros($labels); |
||
13 | |||
14 | foreach ($actualLabels as $index => $actual) { |
||
15 | $predicted = $predictedLabels[$index]; |
||
16 | |||
17 | if (!isset($labels[$actual], $labels[$predicted])) { |
||
18 | continue; |
||
19 | } |
||
20 | |||
21 | if ($predicted === $actual) { |
||
22 | $row = $column = $labels[$actual]; |
||
23 | } else { |
||
24 | $row = $labels[$actual]; |
||
25 | $column = $labels[$predicted]; |
||
26 | } |
||
27 | |||
28 | ++$matrix[$row][$column]; |
||
29 | } |
||
30 | |||
31 | return $matrix; |
||
32 | } |
||
33 | |||
34 | private static function generateMatrixWithZeros(array $labels): array |
||
35 | { |
||
36 | $count = count($labels); |
||
37 | $matrix = []; |
||
38 | |||
39 | for ($i = 0; $i < $count; ++$i) { |
||
40 | $matrix[$i] = array_fill(0, $count, 0); |
||
41 | } |
||
42 | |||
43 | return $matrix; |
||
44 | } |
||
45 | |||
46 | private static function getUniqueLabels(array $labels): array |
||
47 | { |
||
48 | $labels = array_values(array_unique($labels)); |
||
49 | sort($labels); |
||
50 | |||
51 | return array_flip($labels); |
||
0 ignored issues
–
show
Bug
Best Practice
introduced
by
Loading history...
|
|||
52 | } |
||
53 | } |
||
54 |