Add air pollution examples

Author: akondas

classification/airPollution.php

@@ -0,0 +1,34 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpmlExamples;
+
+use Phpml\Classification\KNearestNeighbors;
+use Phpml\Dataset\CsvDataset;
+
+include 'vendor/autoload.php';
+
+$dataset = new CsvDataset(__DIR__.'/../data/air.csv', 2, false, ';');
+
+foreach (range(1, 10) as $k) {
+    $correct = 0;
+    foreach ($dataset->getSamples() as $index => $sample) {
+        $estimator = new KNearestNeighbors($k);
+        $estimator->train($other = removeIndex($index, $dataset->getSamples()), removeIndex($index, $dataset->getTargets()));
+
+        $predicted = $estimator->predict([$sample]);
+
+        if ($predicted[0] === $dataset->getTargets()[$index]) {
+            $correct++;
+        }
+    }
+
+    echo sprintf('Accuracy (k=%s): %.02f%% correct: %s', $k, ($correct / count($dataset->getSamples())) * 100, $correct) . PHP_EOL;
+}
+
+function removeIndex($index, $array): array
+{
+    unset($array[$index]);
+    return $array;
+}

classification/airPollutionVisualization.php

@@ -0,0 +1,32 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpmlExamples;
+
+use Phpml\Classification\KNearestNeighbors;
+use Phpml\Dataset\CsvDataset;
+use Phpml\Math\Distance\Minkowski;
+
+include 'vendor/autoload.php';
+
+$minLat = 41.34343606848294;
+$maxLat = 57.844750992891;
+$minLng = -16.040039062500004;
+$maxLng = 29.311523437500004;
+
+$step = 0.1;
+$k = 3;
+
+$dataset = new CsvDataset(__DIR__.'/../data/air.csv', 2, false, ';');
+$estimator = new KNearestNeighbors($k, new Minkowski());
+$estimator->train($dataset->getSamples(), $dataset->getTargets());
+
+$lines = [];
+for ($lat=$minLat; $lat<$maxLat; $lat+=$step) {
+    for ($lng=$minLng; $lng<$maxLng; $lng+=$step) {
+        $lines[] = sprintf('%s;%s;%s', $lat, $lng, $estimator->predict([[$lat, $lng]])[0]);
+    }
+}
+
+file_put_contents(__DIR__.'/../data/airVis.csv', implode(PHP_EOL, $lines));

classification/languageDetection.php

@@ -1,4 +1,6 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace PhpmlExamples;
 

classification/mnist.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace PhpmlExamples;
 
 use Phpml\Classification\SVC;
@@ -11,8 +13,8 @@
 
 function convert($size)
 {
-    $unit=array('b','kb','mb','gb','tb','pb');
-    return @round($size/pow(1024,($i=floor(log($size,1024)))),2).' '.$unit[$i];
+    $unit=['b','kb','mb','gb','tb','pb'];
+    return @round($size/pow(1024, ($i=floor(log($size, 1024)))), 2).' '.$unit[$i];
 }
 
 $start = $loadStart = microtime(true);

classification/spamFilter.php

@@ -1,4 +1,6 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace PhpmlExamples;
 

composer.json

@@ -18,5 +18,8 @@
   ],
   "require": {
     "php-ai/php-ml": "0.7.0"
+  },
+  "require-dev": {
+    "friendsofphp/php-cs-fixer": "^2.14"
   }
 }