python - Pandas 过滤或删除行多个条件

Question

我有这个数据框boroughCounts，其中包含这些示例值:

    From    To          Count
9   None    Manhattan   302
10  Bronx   Bronx       51
11  Bronx   Manhattan   244
12  None    Brooklyn    8
13  Bronx   Queens      100
14  None    None        67

尝试使用描述的方法过滤掉“From”和“To”列中的 None 值 here或here :

boroughCounts = boroughCounts[(boroughCounts.From != None) & (boroughCounts.To != None)]

boroughCounts = boroughCounts[(boroughCounts["From"] != None) & (boroughCounts["To"] != None)]

但它不起作用，所有值都保持原样。是我用错了，还是有更好的方法？

Answer 1

使用这个，因为 None 是一个字符串，您需要将该字符串替换为 NaN:

df_out = boroughCounts.replace('None', np.nan).dropna()
df_out

输出:

     From         To  Count
10  Bronx      Bronx     51
11  Bronx  Manhattan    244
13  Bronx     Queens    100

或者您可以通过使用“None”来使用 bool 索引:

boroughCounts[(boroughCounts.From != "None") & (boroughCounts.To != "None")]