/**
* Subtracts the given vector from this vector.
*
* @api
* @param self $b The vector to subtract from this vector.
* @return self The difference of the two vectors.
* @throws Exception if the vectors are not in the same vector space.
* @see self::_checkVectorSpace() For exception information.
*/
public function subtract(self $b)
{
return $this->add($b->multiplyByScalar(-1));
}
<?php require "./vendor/nubs/vectorix/src/Vector.php"; use Nubs\Vectorix\Vector; $v = new Vector([2, 5]); $ary = $v->components(); print $ary[0] . " " . $ary[1] . "\n"; $w = $v->multiplyByScalar(3); $ary = $w->components(); print $ary[0] . " " . $ary[1] . "\n";
/**
* Verify that multiplication by a scalar works.
*
* @test
* @uses \Nubs\Vectorix\Vector::__construct
* @uses \Nubs\Vectorix\Vector::components
* @covers ::multiplyByScalar
*/
public function multiplyByScalarWithSimpleValue()
{
$vector = new Vector([1, 2, 3]);
$this->assertSame([3, 6, 9], $vector->multiplyByScalar(3)->components());
}
