public function testPower()
{
$vector1 = new ColumnVector(1, 2, 3, -4);
$vector2 = $vector1->power(3);
$this->assertInstanceOf(ColumnVector::class, $vector2);
$this->assertNotSame($vector2, $vector1);
$this->assertEquals([1.0, 8.0, 27.0, -64.0], $vector2->toArray());
}
