Exemplo n.º 1
0
 /**
  * Return LUP-factorization  P*A=L*U
  *
  * @see http://en.wikipedia.org/wiki/LUP_decomposition
  * @see Introduction to Algorithms by Thomas H. Cormen and other
  * @static
  * @param Matrix $A
  * @return array($C, $P, $singular, $even) - C = L + U - E, $singular === true for singular matrix, $even - for det
  */
 public static function LUP($A)
 {
     if (!Matrix::isMatrix($A)) {
         throw new InvalidArgumentException('Matrix needed. Given' . gettype($A));
     }
     if (!$A->isSquare()) {
         throw new InvalidArgumentException("Matrix must be square");
     }
     $size = $A->getRowsCount();
     $C = clone $A;
     $P = array();
     for ($i = 0; $i < $size; $i++) {
         $P[$i] = $i;
     }
     $singular = false;
     $even = true;
     for ($i = 0; $i < $size; $i++) {
         //поиск опорного элемента
         $pivotValue = 0;
         $pivot = -1;
         for ($row = $i; $row < $size; $row++) {
             if (abs($C->getElem($row, $i)) > $pivotValue) {
                 $pivotValue = abs($C->getElem($row, $i));
                 $pivot = $row;
             }
         }
         if ($pivotValue == 0) {
             $singular = true;
             break;
         }
         //меняем местами i-ю строку и строку с опорным элементом
         if ($pivot !== $i) {
             list($P[$i], $P[$pivot]) = array($P[$pivot], $P[$i]);
             $C->swapRows($pivot, $i);
             $even = !$even;
         }
         for ($j = $i + 1; $j < $size; $j++) {
             $temp = $C->getElem($j, $i) / $C->getElem($i, $i);
             $C->setElem($j, $i, $temp);
             for ($k = $i + 1; $k < $size; $k++) {
                 $temp = $C->getElem($j, $k) - $C->getElem($j, $i) * $C->getElem($i, $k);
                 $C->setElem($j, $k, $temp);
             }
         }
     }
     return array($C, $P, $singular, $even);
 }
Exemplo n.º 2
0
 public function testIsMatrix()
 {
     $matrix = MatrixFactory::identityMatrix(3);
     $this->assertTrue(Matrix::isMatrix($matrix));
     $not_matrix = array(1, 2, 3);
     $this->assertTrue(!Matrix::isMatrix($not_matrix));
     $not_matrix = new stdClass();
     $this->assertTrue(!Matrix::isMatrix($not_matrix));
 }
Exemplo n.º 3
0
 /**
  * Return true if matrices is equals
  *
  * @param Matrix $matrix
  * @param float $eps
  * @return bool
  * @throws InvalidArgumentException
  */
 public function equals($matrix, $eps = 0.0)
 {
     if (!Matrix::isMatrix($matrix)) {
         throw new InvalidArgumentException('Matrix needed. Given' . gettype($matrix));
     }
     if ($eps === 0) {
         return $this->getArray() == $matrix->getArray();
     } else {
         $sub = $this->sub($matrix);
         return $sub->EuclideanNorm() < $eps;
     }
 }