public function testConstructor()
{
$points = [[1, 2], [2, 3], [4, 5], [5, 7], [6, 8]];
$regression = new Linear($points);
$this->assertInstanceOf('MathPHP\\Statistics\\Regression\\Regression', $regression);
$this->assertInstanceOf('MathPHP\\Statistics\\Regression\\Linear', $regression);
}