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  • Bug fixes for general core bugs in 4.0.x will end 8 May 2023 (12 months).
  • Bug fixes for security issues in 4.0.x will end 13 November 2023 (18 months).
  • PHP version: minimum PHP 7.3.0 Note: the minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is also supported.
   1  <?php
   2  
   3  declare(strict_types=1);
   4  
   5  namespace Phpml\Clustering\KMeans;
   6  
   7  use ArrayAccess;
   8  
   9  class Point implements ArrayAccess, \Countable
  10  {
  11      /**
  12       * @var int
  13       */
  14      protected $dimension;
  15  
  16      /**
  17       * @var array
  18       */
  19      protected $coordinates = [];
  20  
  21      /**
  22       * @var mixed
  23       */
  24      protected $label;
  25  
  26      /**
  27       * @param mixed $label
  28       */
  29      public function __construct(array $coordinates, $label = null)
  30      {
  31          $this->dimension = count($coordinates);
  32          $this->coordinates = $coordinates;
  33          $this->label = $label;
  34      }
  35  
  36      public function toArray(): array
  37      {
  38          return $this->coordinates;
  39      }
  40  
  41      /**
  42       * @return float|int
  43       */
  44      public function getDistanceWith(self $point, bool $precise = true)
  45      {
  46          $distance = 0;
  47          for ($n = 0; $n < $this->dimension; ++$n) {
  48              $difference = $this->coordinates[$n] - $point->coordinates[$n];
  49              $distance += $difference * $difference;
  50          }
  51  
  52          return $precise ? $distance ** .5 : $distance;
  53      }
  54  
  55      /**
  56       * @param Point[] $points
  57       */
  58      public function getClosest(array $points): ?self
  59      {
  60          $minPoint = null;
  61  
  62          foreach ($points as $point) {
  63              $distance = $this->getDistanceWith($point, false);
  64  
  65              if (!isset($minDistance)) {
  66                  $minDistance = $distance;
  67                  $minPoint = $point;
  68  
  69                  continue;
  70              }
  71  
  72              if ($distance < $minDistance) {
  73                  $minDistance = $distance;
  74                  $minPoint = $point;
  75              }
  76          }
  77  
  78          return $minPoint;
  79      }
  80  
  81      public function getCoordinates(): array
  82      {
  83          return $this->coordinates;
  84      }
  85  
  86      /**
  87       * @param mixed $offset
  88       */
  89      public function offsetExists($offset): bool
  90      {
  91          return isset($this->coordinates[$offset]);
  92      }
  93  
  94      /**
  95       * @param mixed $offset
  96       *
  97       * @return mixed
  98       */
  99      public function offsetGet($offset)
 100      {
 101          return $this->coordinates[$offset];
 102      }
 103  
 104      /**
 105       * @param mixed $offset
 106       * @param mixed $value
 107       */
 108      public function offsetSet($offset, $value): void
 109      {
 110          $this->coordinates[$offset] = $value;
 111      }
 112  
 113      /**
 114       * @param mixed $offset
 115       */
 116      public function offsetUnset($offset): void
 117      {
 118          unset($this->coordinates[$offset]);
 119      }
 120  
 121      public function count(): int
 122      {
 123          return count($this->coordinates);
 124      }
 125  }