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See Release Notes

  • 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.

Differences Between: [Versions 310 and 400] [Versions 39 and 400]

   1  <?php
   2  
   3  namespace Matrix\Operators;
   4  
   5  use Matrix\Matrix;
   6  use Matrix\Exception;
   7  
   8  class Subtraction extends Operator
   9  {
  10      /**
  11       * Execute the subtraction
  12       *
  13       * @param mixed $value The matrix or numeric value to subtract from the current base value
  14       * @throws Exception If the provided argument is not appropriate for the operation
  15       * @return $this The operation object, allowing multiple subtractions to be chained
  16       **/
  17      public function execute($value): Operator
  18      {
  19          if (is_array($value)) {
  20              $value = new Matrix($value);
  21          }
  22  
  23          if (is_object($value) && ($value instanceof Matrix)) {
  24              return $this->subtractMatrix($value);
  25          } elseif (is_numeric($value)) {
  26              return $this->subtractScalar($value);
  27          }
  28  
  29          throw new Exception('Invalid argument for subtraction');
  30      }
  31  
  32      /**
  33       * Execute the subtraction for a scalar
  34       *
  35       * @param mixed $value The numeric value to subtracted from the current base value
  36       * @return $this The operation object, allowing multiple additions to be chained
  37       **/
  38      protected function subtractScalar($value): Operator
  39      {
  40          for ($row = 0; $row < $this->rows; ++$row) {
  41              for ($column = 0; $column < $this->columns; ++$column) {
  42                  $this->matrix[$row][$column] -= $value;
  43              }
  44          }
  45  
  46          return $this;
  47      }
  48  
  49      /**
  50       * Execute the subtraction for a matrix
  51       *
  52       * @param Matrix $value The numeric value to subtract from the current base value
  53       * @return $this The operation object, allowing multiple subtractions to be chained
  54       * @throws Exception If the provided argument is not appropriate for the operation
  55       **/
  56      protected function subtractMatrix(Matrix $value): Operator
  57      {
  58          $this->validateMatchingDimensions($value);
  59  
  60          for ($row = 0; $row < $this->rows; ++$row) {
  61              for ($column = 0; $column < $this->columns; ++$column) {
  62                  $this->matrix[$row][$column] -= $value->getValue($row + 1, $column + 1);
  63              }
  64          }
  65  
  66          return $this;
  67      }
  68  }