Is there a way to copy only the structure (not the data) of a Pandas DataFrame?

Question

I received a DataFrame from somewhere and want to create another DataFrame with the same number and names of columns and rows (indexes). For example, suppose that the origin

Answer 1

You can simply mask by notna() i.e

df1 = pd.DataFrame([[11, 12], [21, 22]], columns=['c1', 'c2'], index=['i1', 'i2'])

df2 = df1.mask(df1.notna())

    c1  c2
i1 NaN NaN
i2 NaN NaN