pandas - Extend Index of a DataFrame setting all columns for new rows to NaN?

Question

I have time-indexed data:

df2 = pd.DataFrame({ \'day\': pd.Series([date(2012, 1, 1), date(2012, 1, 3)]), \'b\' : pd.Series([0.22, 0.3]) })
df2 = df2.set_index(\'         


        

Answer 1

def extendframe(df, ndays):
    """
    (df, ndays) -> df that is padded by ndays in beginning and end
    """
    ixd = df.index - datetime.timedelta(ndays)
    ixu = df.index + datetime.timedelta(ndays)
    ixx = df.index.union(ixd.union(ixu))
    df_ = df.reindex(ixx)
    return df_