python - 如何根据另一列填充列中的缺失值

Question

我有一个名为 shoes 的数据框

Brand   Comment
Ugg       NaN
Prada     NaN
Clarks    NaN
Ugg       NaN
Clark     NaN
Prada     Made from horse leather
Prada     Made from pig leather
Prada     NaN
Ugg       Made from Australian cow leather
...

另一个数据框 df_mode 是通过将鞋数据框中每个鞋品牌的评论模式获取非空值而获得的

Brand  Comment
Ugg    Made from sheep 
Prada  Made from pig leather
Clarks Made from Cow leather

如何为鞋子数据框中的每个鞋品牌分配缺失值，并在 df_mode 数据框中显示其各自的模式响应。

这基本上是我想要实现的

Brand   Comment
Ugg       Made from sheep
Prada     Made from pig leather
Clarks    Made from Cow leather
Ugg       Made from sheep
Clark     Made from Cow leather
Prada     Made from horse leather
Prada     Made from pig leather
Prada     Made from pig leather
Ugg       Made from Australian cow leather

标签： pythonpandasdataframe

Answer 1

使用np.where

shoes['Comment']=np.where(shoes['Comment'].isnull(),shoes['Brand'].map(dict(zip(df_mode['Brand']))),df_mode['Comment'],shoes['Comment'])