Python Pandas：AttributeError：'str'对象没有属性'loc'
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时间：2020-09-14 04:29:51 来源:igfitidea点击:
Python Pandas: AttributeError: 'str' object has no attribute 'loc'
提问by jeangelj
Working with dataframe df:
使用数据框 df：
Count
1
2
3
4
5
Want to add second column, that categorizes everything above 3 as '4+' - needed output:
想要添加第二列，将 3 以上的所有内容归类为“4+” - 需要的输出：
Count | Category
1 1
2 2
3 3
4 4+
5 4+
This is my code:
这是我的代码：
df['Category'] = df['Count']
df = df.loc[df['Count'] > 3, 'Category'] = '4+'
And I get this error:
我收到这个错误：
AttributeError: 'str' object has no attribute 'loc'
回答by Vaishali
Just go with
随走
df['Category'] = df['Count']
df.loc[df['Count'] > 3, 'Category'] = '4+'
回答by Cedric Zoppolo
You can try out with:
你可以试试：
import pandas as pd
df = pd.DataFrame({"Count": [1,2,3,4,5]})
df["Category"] = df["Count"].apply(str)
df["Category"][df['Count'] > 3] = "4+"
Output would be:
输出将是：
>>> df
Count Category
0 1 1
1 2 2
2 3 3
3 4 4+
4 5 4+
