问题

我有一个经过清理的pandas数据帧，只包含一个邮政编码列，我试图使用pyzipcode在执行时返回相应的州名到一个新列中：

```python
from pyzipcode import ZipCodeDatabase
import pandas as pd
import os
zcdb = ZipCodeDatabase()

df = pd.read_excel(r'G:\Downloads\testzip.xlsx')
df[pd.to_numeric(df['Zip'], errors='coerce').notnull()]
df = df.dropna

df['state'] = df['Zip'].map(lambda x: zcdb[x].state)

不幸的是，我收到了以下错误：

'method' object is not subscriptable

不知道为什么。有人知道这里发生了什么吗？

<details>
<summary>英文:</summary>

I have a cleansed pandas dataframe that just contains a single column of zip codes, and I&#39;m trying to use pyzipcode to return the corresponding state in a new column by executing: 

from pyzipcode import ZipCodeDatabase
import pandas as pd
import os
zcdb = ZipCodeDatabase()

df = pd.read_excel(r'G:\Downloads\testzip.xlsx')
df[pd.to_numeric(df['Zip'], errors='coerce').notnull()]
df = df.dropna

df['state'] = df['Zip'].map(lambda x: zcdb[x].state)

Unfortunately, I get the following error: 

'method' object is not subscriptable

No idea why. Anyone know what's happening here? 

</details>


# 答案1
**得分**: 2

`df = df.dropna` 用它的 `dropna` 方法替换了你的数据框。这导致 `df['Zip']` 引发了你所看到的异常。将其替换为 `df = df.dropna()`，这将调用方法，我相当确定这是你想要的。

<details>
<summary>英文:</summary>

`df = df.dropna` replaces your dataframe by its `dropna` method. This causes `df[&#39;Zip&#39;]` to raise the exception you see. Replace it with `df = df.dropna()`, which calls the method instead - I am fairly sure that&#39;s what you want.

</details>