我对ckan有一些疑问:
如何:
- 从网络加载 CKAN 数据集
- 将此数据集转换为 pandas 数据框
而且我需要在ckan网站上注册才能查询数据吗?
我使用的是 Pyhton 3.6.1
编辑 2: 我尝试过以下代码:
import urllib
url = 'http://dados.cvm.gov.br/api/action/datastore_search?resource_id=92741280-58fc-446b-b436-931faaca4fb4&q=CNPJ_FUNDO:11.286.399/0001-35'
fileobj = urllib.request.urlopen(url)
print(fileobj.read())
但是,结果是这样的:
b'{"help": "http://dados.cvm.gov.br/api/3/action/help_show?name=datastore_search", "success": true, "result": {"resource_id": "92741280-58fc-446b-b436-931faaca4fb4", "fields": [{"type": "int4", "id": "_id"}, {"type": "text", "id": "CNPJ_FUNDO"}, {"type": "timestamp", "id": "DT_COMPTC"}, {"type": "numeric", "id": "VL_TOTAL"}, {"type": "numeric", "id": "VL_QUOTA"}, {"type": "numeric", "id": "VL_PATRIM_LIQ"}, {"type": "numeric", "id": "CAPTC_DIA"}, {"type": "numeric", "id": "RESG_DIA"}, {"type": "numeric", "id": "NR_COTST"}, {"type": "int8", "id": "_full_count"}, {"type": "float4", "id": "rank"}], "q": "CNPJ_FUNDO:11.286.399/0001-35", "records": [], "_links": {"start": "/api/action/datastore_search?q=CNPJ_FUNDO%3A11.286.399%2F0001-35&resource_id=92741280-58fc-446b-b436-931faaca4fb4", "next": "/api/action/datastore_search?q=CNPJ_FUNDO%3A11.286.399%2F0001-35&offset=100&resource_id=92741280-58fc-446b-b436-931faaca4fb4"}}}'
我需要像 this image 这样的结果
最佳答案
- load a CKAN dataset from web
您链接的网站在链接“API de Dados”中有一个 Python 示例:
import urllib
url = 'http://dados.cvm.gov.br/api/action/datastore_search?resource_id=92741280-58fc-446b-b436-931faaca4fb4&limit=5&q=title:jones'
fileobj = urllib.urlopen(url)
print fileobj.read()
- transform this dataset into a pandas dataframe
像处理任何 JSON 数据集一样,解析它并加载到数据帧中(这里没有任何特定于 ckan 的内容):
>>> import pandas as pd
>>> import json
>>> response = json.loads(fileobj.read())
>>> pd.DataFrame(response['result']['records'])
CAPTC_DIA CNPJ_FUNDO DT_COMPTC NR_COTST RESG_DIA \
0 0.00 00.017.024/0001-53 2017-07-03T00:00:00 1 0.00
1 0.00 00.017.024/0001-53 2017-07-04T00:00:00 1 0.00
2 0.00 00.017.024/0001-53 2017-07-05T00:00:00 1 0.00
3 0.00 00.017.024/0001-53 2017-07-06T00:00:00 1 0.00
4 0.00 00.017.024/0001-53 2017-07-07T00:00:00 1 0.00
VL_PATRIM_LIQ VL_QUOTA VL_TOTAL _id
0 1111752.99 25.249352000000 1111831.24 1
1 1112087.29 25.256944400000 1112268.26 2
2 1112415.28 25.264393500000 1112716.06 3
3 1112754.06 25.272087600000 1113165.75 4
4 1113096.62 25.279867600000 1113293.06 5
And i need have a register in ckan website to query the data?
您不需要在您链接的网站上注册,我无需注册即可检索数据。我更喜欢使用 requests
库:
import requests
import pandas as pd
params = params={
'resource_id': '92741280-58fc-446b-b436-931faaca4fb4',
'limit': 5,
}
url = 'http://dados.cvm.gov.br/api/action/datastore_search'
r = requests.get(url, params=params).json()
df = pd.DataFrame(r['result']['records'])
看起来像 limit
and offset
parameters probably behave like in SQL 。您可能必须将列转换为数字/日期类型,同样,这并不是 ckan 特有的,您可以在 pandas 文档中找到有关如何执行此操作的答案。
>>> df.describe()
_id
count 5.000000
mean 3.000000
std 1.581139
min 1.000000
25% 2.000000
50% 3.000000
75% 4.000000
max 5.000000
转换很容易:
>>> for col in ('CAPTC_DIA', 'NR_COTST', 'RESG_DIA', 'VL_PATRIM_LIQ', 'VL_QUOTA', 'VL_TOTAL'):
... df[col] = pd.to_numeric(df[col])
>>> df['DT_COMPTC'] = pd.to_datetime(df['DT_COMPTC'])
>>> df.describe()
CAPTC_DIA NR_COTST RESG_DIA VL_PATRIM_LIQ VL_QUOTA VL_TOTAL \
count 5.0 5.0 5.0 5.000000e+00 5.000000 5.000000e+00
mean 0.0 1.0 0.0 1.112421e+06 25.264529 1.112655e+06
std 0.0 0.0 0.0 5.303356e+02 0.012045 6.123444e+02
min 0.0 1.0 0.0 1.111753e+06 25.249352 1.111831e+06
25% 0.0 1.0 0.0 1.112087e+06 25.256944 1.112268e+06
50% 0.0 1.0 0.0 1.112415e+06 25.264394 1.112716e+06
75% 0.0 1.0 0.0 1.112754e+06 25.272088 1.113166e+06
max 0.0 1.0 0.0 1.113097e+06 25.279868 1.113293e+06
_id
count 5.000000
mean 3.000000
std 1.581139
min 1.000000
25% 2.000000
50% 3.000000
75% 4.000000
max 5.000000
关于python - 加载CKAN数据集,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/45418664/