使用 get() 函数读取 GTFS tripupdates.pb 实时数据时出错

Question

我们希望使用以下代码从实体内的列表中提取停靠站到达时间和出发时间。但是，我不断收到错误。

dict_obj['entity'][0]

Gives the following output


{'id': '8800314',
 'tripUpdate': {'trip': {'tripId': '8800314',
   'startTime': '11:30:00',
   'startDate': '20240313',
   'routeId': '20832'},
  'stopTimeUpdate': [{'stopSequence': 1,
    'arrival': {'time': '1710344086'},
    'departure': {'time': '1710344086'},
    'stopId': '86900',
    'stopTimeProperties': {}},
   {'stopSequence': 2,
    'arrival': {'time': '1710343956'},
    'departure': {'time': '1710343956'},
    'stopId': '86024',
    'stopTimeProperties': {}},
   {'stopSequence': 3,
    'arrival': {'time': '1710343995'},
    'departure': {'time': '1710343995'},
    'stopId': '86560',
    'stopTimeProperties': {}},
   {'stopSequence': 4,

我们要提取到达时间：

#for trip updates

collector1 = []
counter1=0
for block1 in dict_obj1['entity']:
    counter1 += 1
    row = OrderedDict()
    row['stop_AT'] = block1.get('tripUpdate').get('stopTimeUpdate')[0].get('arrival').get('time')
    row['stop_DT'] = block1.get('tripUpdate').get('stopTimeUpdate')[0].get('departure').get('time')
    collector1.append(row)
df1 = pd.DataFrame(collector1)        

Error:

AttributeError: 'list' object has no attribute 'get'

代码来源：

https://nbviewer.org/url/nikhilvj.co.in/files/gtfsrt/locations.ipynb#

Answer 1

以下是如何从这本字典中获取到达和出发时间的示例：

dct = {
    "id": "8800314",
    "tripUpdate": {
        "trip": {
            "tripId": "8800314",
            "startTime": "11:30:00",
            "startDate": "20240313",
            "routeId": "20832",
        },
        "stopTimeUpdate": [
            {
                "stopSequence": 1,
                "arrival": {"time": "1710344086"},
                "departure": {"time": "1710344086"},
                "stopId": "86900",
                "stopTimeProperties": {},
            },
            {
                "stopSequence": 2,
                "arrival": {"time": "1710343956"},
                "departure": {"time": "1710343956"},
                "stopId": "86024",
                "stopTimeProperties": {},
            },
            {
                "stopSequence": 3,
                "arrival": {"time": "1710343995"},
                "departure": {"time": "1710343995"},
                "stopId": "86560",
                "stopTimeProperties": {},
            },
        ],
    },
}

for d in dct["tripUpdate"]["stopTimeUpdate"]:
    arrival = d["arrival"]["time"]
    departure = d["departure"]["time"]

    print(f"{arrival=} {departure=}")

打印：

arrival='1710344086' departure='1710344086'
arrival='1710343956' departure='1710343956'
arrival='1710343995' departure='1710343995'