public function product(Matrix $matrix)
{
if ($this->columns !== $matrix->getRows()) {
return false;
}
$c = $matrix->getColumns();
$result = new Matrix($this->rows, $c);
for ($i = 0; $i < $this->rows; ++$i) {
for ($j = 0; $j < $c; ++$j) {
$sum = 0;
for ($k = 0; $k < $this->columns; ++$k) {
$sum += $this->matrix[$i][$k] * $matrix->getElement($k, $j);
}
$result->setElement($i, $j, $sum);
}
}
return $result;
}
/**
* Create a matrix from an array of doubles.
*
* @param
* sourceMatrix
* An array of doubles.
*/
public static function matrixFromDoubles(array $sourceMatrix)
{
$out = new Matrix(count($sourceMatrix), count($sourceMatrix[0]));
for ($r = 0; $r < $out->getRows(); ++$r) {
for ($c = 0; $c < $out->getCols(); ++$c) {
$out->set($r, $c, $sourceMatrix[$r][$c]);
}
}
return $out;
}
public function testSize()
{
$matrix = new Matrix([[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12]]);
$this->assertEquals(3, $matrix->getRows());
$this->assertEquals(4, $matrix->getCols());
}
