如果一个值是 NaN，Pandas 用 NaN 替换一行中的所有项目

Question

I want to get rid of some records with NaNs. This works perfectly:

df.dropna(axis=0, how='any',inplace=True)

However, it changes the shape of my dataframe, and the index is no longer uniformly spaced. Therefore, I'd like to replace all items in these rows with np.nan . Is there a simple way to do this?

I was thinking about resampling the dataframe after dropna , but that only seems to work with a prescribed interval, whereas I would rather use the original index. Another approach would be to loop over the dataframe with iterrows , but that also feels cumbersome.

Answer 1

下面的命令选择具有等于 Nan 的任何值的所有行，并将 NaN 分配给这些行的其余部分。

df.loc[df.isnull().any(axis=1), :] = np.nan

Answer 2

使用此代码也无需切片df = df.replace('nan',np.nan)