I need to merge the label dataframe to the feature dataframe like this:

Label Dataframe:

Feature Dataframe:

the result dataframe should be something like this:

which means, for example in 0~1s, the label is a; in 1~2s,the label is b; etc.

I have 100,000 rows in the actural dataframe. Is there any efficient way to do this?

CodePudding user response：

One option is

df2['Label'] = df2['Time'].astype(int).map(df1.set_index('Time').squeeze())

CodePudding user response：

You can try this: df1.merge(df2)

The official documentation