Python：我怎样才能遍历这段代码中的所有值？ [复制]

Question

我想从 API 获取信息。 我需要获取这些行的信息：

Lines = ["Piccadilly", "Victoria", "Bakerloo", "Central", "Circle" , "District", "Jubilee", "Metropolitan", "Northern"]

所以我创建了这段代码：

url = 'https://api.tfl.gov.uk/Line/'
tag = '?app_id=XXXXX&app_key=YYYYYYY'

for Line in Lines:
    r = rq.get(url + str(Line) + tag)
    time.sleep(2)
    info = json.loads(r.content)
info

我得到的信息仅适用于 Lines 的最后一个组件，我想将 Lines 中每个组件的信息保存在数据框中。

这是我只为北方得到的

[{'$type': 'Tfl.Api.Presentation.Entities.Line, Tfl.Api.Presentation.Entities',
  'id': 'northern',
  'name': 'Northern',
  'modeName': 'tube',
  'disruptions': [],
  'created': '2019-08-20T16:25:25.35Z',
  'modified': '2019-08-20T16:25:25.35Z',
  'lineStatuses': [],
  'routeSections': [],
  'serviceTypes': [{'$type': 'Tfl.Api.Presentation.Entities.LineServiceTypeInfo, Tfl.Api.Presentation.Entities',
    'name': 'Regular',
    'uri': '/Line/Route?ids=Northern&serviceTypes=Regular'},
   {'$type': 'Tfl.Api.Presentation.Entities.LineServiceTypeInfo, Tfl.Api.Presentation.Entities',
    'name': 'Night',
    'uri': '/Line/Route?ids=Northern&serviceTypes=Night'}],
  'crowding': {'$type': 'Tfl.Api.Presentation.Entities.Crowding, Tfl.Api.Presentation.Entities'}}]

有什么想法吗？

Answer 1

将信息附加到这样的列表中：

# create empty list
info = []

for Line in Lines:
    r = rq.get(url + str(Line) + tag)
    time.sleep(2)
    # append to list
    info.append(json.loads(r.content))
info

假设您已经创建了一个名为 df 的数据框，您可以使用它将该行插入数据框：

    import pandas as pd
    import json

    # put all columns in a list
    columns = ['id', 'name', 'modeName'] # incomplete list

    def insert(df, row):
            # get highest index
            insert_loc = df.index.max()
            # insert row
            if pd.isna(insert_loc):
                    df.loc[0] = row
            else:
                    df.loc[insert_loc + 1] = row

    for record in info:
            row = []
            for col in columns:
                    row.append(info[col])
            insert(df,row)

Answer 2

您正在重新分配/覆盖info。使用列表或字典等数据结构添加/附加到它。

info={}
for Line in Lines:
    r = rq.get(url + str(Line) + tag)
    time.sleep(2)
    info[Line] = json.loads(r.content)

Answer 3

你可以这样做

url = 'https://api.tfl.gov.uk/Line/'
tag = '?app_id=XXXXX&app_key=YYYYYYY'

info={}
for Line in Lines:
    r = rq.get(url + str(Line) + tag)
    time.sleep(2)
    info[Line]=r.json()
print(info)

Answer 4

您在循环中的每次迭代中都覆盖了信息。一种方法是推动每个 在列表中返回 json。

url = 'https://api.tfl.gov.uk/Line/'
tag = '?app_id=XXXXX&app_key=YYYYYYY'
infos = []

for Line in Lines:
    r = rq.get(url + str(Line) + tag)
    time.sleep(2)
    infos.append(json.loads(r.content))

print(infos)