public function testDistanceTo()
{
$geo1 = new Geo(array('latitude' => '30.006003', 'longitude' => '-90.10947'));
$geo2 = new Geo(array('latitude' => '32.919104', 'longitude' => '-96.77497'));
$this->assertEquals(441.24, $geo1->distanceTo($geo2, 2));
}