Parsing XML var_dump is NULL

[andy1212]

I'm trying to parse xml I loaded onto the page by simplexml_load_file and I'm using the following code to try to do this,

 

 

$resp = simplexml_load_file($request_url);
$shipping = $resp->rate[15]['total_charge'];
var_dump($shipping);

 

However I get NULL. Here is what the xml looks like when var dumped from $resp.

 

object(SimpleXMLElement)#1 (1) { ["rate"]=> object(SimpleXMLElement)#2 (1) { ["@attributes"]=> array(15) { ["weight"]=> string(3) "5.0" ["weight_unit"]=> string(2) "lb" ["zone"]=> string(1) "3" ["transit_time"]=> string(1) "1" ["transit_time_guaranteed"]=> string(5) "false" ["estimated_delivery_date"]=> string(10) "2013-07-31" ["base_charge"]=> string(5) "11.05" ["freight_charge"]=> string(5) "11.05" ["residential_address_charge"]=> string(4) "2.75" ["net_charge"]=> string(5) "13.80" ["fuel_surcharge_rate"]=> string(4) "17.3" ["fuel_surcharge"]=> string(4) "1.91" ["subtotal_charge"]=> string(5) "15.71" ["on_hst_charge"]=> string(4) "2.04" ["total_charge"]=> string(5) "17.75" } } }

 

and I'm trying to put this guy, ["total_charge"]=>string(5) "17.75" into it's own variable in php called $shipping so I can echo it out as $17.75.

 

Thanks for your time.