How to add an empty column to a dataframe?

Question

What\'s the easiest way to add an empty column to a pandas DataFrame object? The best I\'ve stumbled upon is something like

df[\'foo\'] = df.ap         


        

Answer 1

I like:

df['new'] = pd.Series(dtype='your_required_dtype')

If you have an empty dataframe, this solution makes sure that no new row containing only NaN is added.

Specifying dtype is not strictly necessary, however newer Pandas versions produce a DeprecationWarning if not specified.