Php Google direction API为TrafficModel返回不正确的值

根据GoogleAPI文档，所有的流量模型都应该有不同的值，但我得到的最佳猜测、悲观、乐观的值是相同的

我正在使用下面的代码

//Source address
$a = 'Los Angeles International Airport, 1 World Way, Los Angeles, CA 90045, United States'; 
//Destination address
$b = 'Beverly Wilshire, Beverly Hills (A Four Seasons Hotel), 9500 Wilshire Boulevard, Beverly Hills, CA 90212, United
        States';
//Pass source and destination address in google map API for PESSIMISTIC
$url = 'https://maps.googleapis.com/maps/api/directions/xml?origin='. urlencode($a).'&destination='. urlencode($b).'&departure_time=1451491810&travelMode=google.maps.TravelMode.DRIVING&drivingOptions=trafficModel:google.maps.TrafficModel.PESSIMISTIC&key=AIzaSyC7h7m5bRs-BZwk0XTXEQTB74dZujeLzZs';
//output:  duration_in_traffic = 50 mins

//Pass source and destination address in google map API for OPTIMISTIC
$url = 'https://maps.googleapis.com/maps/api/directions/xml?origin='. urlencode($a).'&destination='. urlencode($b).'&departure_time=1451491810&travelMode=google.maps.TravelMode.DRIVING&drivingOptions=trafficModel:google.maps.TrafficModel.OPTIMISTIC&key=AIzaSyC7h7m5bRs-BZwk0XTXEQTB74dZujeLzZs';
//output:  duration_in_traffic = 50 mins

//Pass source and destination address in google map API for BEST_GUESS
$url = 'https://maps.googleapis.com/maps/api/directions/xml?origin='. urlencode($a).'&destination='. urlencode($b).'&departure_time=1451491810&travelMode=google.maps.TravelMode.DRIVING&drivingOptions=trafficModel:google.maps.TrafficModel.BEST_GUESS&key=AIzaSyC7h7m5bRs-BZwk0XTXEQTB74dZujeLzZs';
    //output:  duration_in_traffic = 50 mins

更新：

我正在使用

//出发时间=2016年1月4日/1451898000

$url = 'https://maps.googleapis.com/maps/api/directions/xml?origin='. urlencode($a).'&destination='. urlencode($b).'&departure_time=1451898000&mode=driving&traffic_model=pessimistic&key=AIzaSyC7h7m5bRs-BZwk0XTXEQTB74dZujeLzZs';

//Output

pessimistic==>>
duration_in_traffic => 31 mins

optimistic==>
duration_in_traffic => 25 mins

best_guess==>
duration_in_traffic => 25 mins

Above responses are not correct as per the live google map

https://www.google.com/maps/dir/Los+Angeles+International+Airport,+1+World+Way,+Los+Angeles,+CA+90045,+United+States/Beverly+Hills,+CA/@34.0077875,-118.4878535,12z/data=!3m1!4b1!4m17!4m16!1m5!1m1!1s0x80c2b0d213b24fb5:0x77a87b57698badf1!2m2!1d-118.40853!2d33.9415889!1m5!1m1!1s0x80c2bc04d6d147ab:0xd6c7c379fd081ed1!2m2!1d-118.4003563!2d34.0736204!2m3!6e0!7e2!8j1451898000

---

我做错了什么？

您部分使用了Javascript API的参数，但必须使用Javascript API的参数

一,

应该是

    mode=driving

（您可以省略它，这是默认值）

二,

一定是

 traffic_model=[value]

其中，

[value]

可能是

最佳猜测

，

乐观

或

悲观

---

因此，

$url

应该是

$url = 'https://maps.googleapis.com/maps/api/directions/xml?origin='. urlencode($a).'&destination='. urlencode($b).'&departure_time=1451491810&mode=driving&traffic_model=pessimistic&key=AIzaSyC7h7m5bRs-BZwk0XTXEQTB74dZujeLzZs';

交通持续时间=1小时19分钟

交通中的持续时间=28分钟

---

duration_in_traffic=50分钟

我们能在一个google API调用中传递某种程度上的悲观、乐观和最佳猜测，并能在同一个调用中返回悲观、乐观和最佳猜测的响应吗？好吧，现在不可能了，你检查过我更新的代码了吗？我将日期定为2016年1月，但其响应不正确。

 traffic_model=[value]

$url = 'https://maps.googleapis.com/maps/api/directions/xml?origin='. urlencode($a).'&destination='. urlencode($b).'&departure_time=1451491810&mode=driving&traffic_model=pessimistic&key=AIzaSyC7h7m5bRs-BZwk0XTXEQTB74dZujeLzZs';