/**
* Calculates the dot product between this vector and the given vector.
*
* @param Vector $vector The vector to calculate thet dot product with.
* @return float
*/
public function dotProduct(Vector $vector)
{
if ($this->getSize() !== $vector->getSize()) {
throw new InvalidArgumentException('Invalid vector provided. The size should be the same.');
}
$result = new BigNumber();
$vectorSize = $this->getSize();
for ($i = 0; $i < $vectorSize; ++$i) {
$value = new BigNumber($this[$i]);
$value->multiply($vector[$i]);
$result->add($value);
}
return $result;
}
/**
* Multiplies the two given numbers.
*
* @param BigNumber $lft The left number.
* @param BigNumber $rgt The right number.
* @param int $scale The scale of the calculated number.
* @param bool $mutable Whether or not the result is mutable.
* @return BigNumber
*/
public static function multiply(BigNumber $lft, BigNumber $rgt, $scale = 10, $mutable = true)
{
$bigNumber = new BigNumber($lft, $scale, $mutable);
return $bigNumber->multiply($rgt);
}
public function testWithMutableTrue()
{
// Arrange
$bigNumber = new BigNumber('5', 10, true);
// Act
$newBigNumber = $bigNumber->multiply(10);
// Assert
$this->assertInstanceOf('PHP\\Math\\BigNumber\\BigNumber', $bigNumber);
$this->assertInstanceOf('PHP\\Math\\BigNumber\\BigNumber', $newBigNumber);
$this->assertEquals('50', $bigNumber->getValue());
$this->assertEquals('50', $newBigNumber->getValue());
}
