python - 如何解决类型错误: 'numpy.ndarray' object is not callable on Python

Question

我正在努力在 python 中聚合 Json 文件我使用列表理解来获取所有负责机构

import pandas as pd
import numpy as np

url = "http://311api.cityofchicago.org/open311/v2/requests.json";
d= pd.read_json(url)     
ar = [x.get("agency_responsible") for x in d.values()] 

我收到此错误:

Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: 'numpy.ndarray' object is not callable

然后我尝试通过添加 numpy 并处理数组来解决这个问题。

  import numpy as np
    np.[x.get("agency_responsible") for x in d.values()]

但是好像不行啊!

Answer 1

values 是 DataFrame 的属性，而不是方法。只需使用 d.values 即可访问数组。

事实上，我认为你想要的很简单:

ar = d['agency_responsible'].values

或

ar = d.agency_responsible.values

这是一个实际的 session :

In [1]: import pandas as pd

In [2]: url = "http://311api.cityofchicago.org/open311/v2/requests.json"

In [3]: d = pd.read_json(url)

In [4]: type(d)
Out[4]: pandas.core.frame.DataFrame

In [5]: ar = d.agency_responsible.values

In [6]: ar[0]
Out[6]: u'Bureau of Street Operations - Graffiti'

In [7]: ar[:4]
Out[7]: 
array([u'Bureau of Street Operations - Graffiti',
       u'Division of Electrical Operations CDOT',
       u'Bureau of Rodent Control - S/S',
       u'Division of Electrical Operations CDOT'], dtype=object)