TypeError passing Series with dtype int to dateutil.relativedelta

Question

I'm trying to use dateutil.relativedelta.relativedelta to add an int type pandas Series to a datetime Series.

df.loc[:,'calc_eli_date'] = (
    datetime.datetime(df['pol_eff_date'])
    + relativedelta(years=df['frt_elig_year'])
)

df['pol_eff_date'] is datetime64[ns] type

df['frt_elig_year'] is int

But I get the following error:

TypeError: cannot convert the series to class 'int' 

Answer 1

The dateutil.relativedata.relativedata constructor only accepts datetime and integer arguments - not arrays or pandas objects.

Try pd.to_timedelta instead:

df['calc_eli_date'] = (
    df['pol_eff_date'] + pd.to_timedelta(df['frt_elig_year'], unit='Y')
)