def format_index(df):
<EOL>year = int(df.columns[<NUM_LIT:1>])<EOL>df_doy = df[df.columns[<NUM_LIT:0>]]<EOL>df_time = df[df.columns[<NUM_LIT:1>]] - <NUM_LIT:1><EOL>fifty_nines = df_time % <NUM_LIT:100> == <NUM_LIT><EOL>times = df_time.where(~fifty_nines, df_time - <NUM_LIT>)<EOL>times = times.apply(lambda x: '<STR_LIT>'.format(x))<EOL>doy = df_doy.apply(lambda x: '<STR_LIT>'.format(x))<EOL>dts = pd.to_datetime(str(year) + '<STR_LIT:->' + doy + '<STR_LIT:->' + times,<EOL>format='<STR_LIT>')<EOL>df.index = dts<EOL>df = df.tz_localize('<STR_LIT>')<EOL>return df<EOL>
Create a datetime index from day of year, and time columns.

    Parameters
    ----------
    df: pd.Dataframe
        The srml data to reindex.

    Returns
    -------
    df: pd.Dataframe
        The Dataframe with a DatetimeIndex localized to 'Etc/GMT+8'.