Coerce an array of datetime-like values to a pandas Series and
    apply requested rounding

def _round_series(values, name, freq):
    """Coerce an array of datetime-like values to a pandas Series and
    apply requested rounding
    """
    values_as_series = pd.Series(values.ravel())
    method = getattr(values_as_series.dt, name)
    field_values = method(freq=freq).values

    return field_values.reshape(values.shape)