Location\Polygon::getPerimeter PHP Method

    public function getPerimeter(DistanceInterface $calculator)
    {
        $perimeter = 0.0;
        if (count($this->points) < 2) {
            return $perimeter;
        }
        foreach ($this->getSegments() as $segment) {
            $perimeter += $segment->getLength($calculator);
        }
        return $perimeter;
    }

 public function testIfPerimeterCalculationWorksAsExpected()
 {
     $polygon = new Polygon();
     $polygon->addPoint(new Coordinate(10, 10));
     $polygon->addPoint(new Coordinate(10, 20));
     $polygon->addPoint(new Coordinate(20, 20));
     $polygon->addPoint(new Coordinate(20, 10));
     // http://geographiclib.sourceforge.net/cgi-bin/Planimeter?type=polygon&rhumb=geodesic&input=10+10%0D%0A10+20%0D%0A20+20%0D%0A20+10&norm=decdegrees&option=Submit
     $this->assertEquals(4355689.472548, $polygon->getPerimeter(new Vincenty()), '', 0.01);
     $polygon = new Polygon();
     $polygon->addPoint(new Coordinate(52, 13));
     $polygon->addPoint(new Coordinate(53, 13));
     $polygon->addPoint(new Coordinate(53, 12));
     $polygon->addPoint(new Coordinate(52, 12));
     // http://geographiclib.sourceforge.net/cgi-bin/Planimeter?type=polygon&rhumb=geodesic&input=52+13%0D%0A53+13%0D%0A53+12%0D%0A52+12&norm=decdegrees&option=Submit
     $this->assertEquals(358367.809428, $polygon->getPerimeter(new Vincenty()), '', 0.01);
 }