Generating random dates within a given range in pandas

by

Is converting to the unix timestamp acceptable?

def random_dates(start, end, n=10):

    start_u = start.value//10**9
    end_u = end.value//10**9

    return pd.to_datetime(np.random.randint(start_u, end_u, n), unit="s")

Sample run:

start = pd.to_datetime('2015-01-01')
end = pd.to_datetime('2018-01-01')
random_dates(start, end)

DatetimeIndex(['2016-10-08 07:34:13', '2015-11-15 06:12:48',
               '2015-01-24 10:11:04', '2015-03-26 16:23:53',
               '2017-04-01 00:38:21', '2015-05-15 03:47:54',
               '2015-06-24 07:32:32', '2015-11-10 20:39:36',
               '2016-07-25 05:48:09', '2015-03-19 16:05:19'],
              dtype="datetime64[ns]", freq=None)

EDIT:

As per the comment by @smci, I wrote a function to accommodate both 1 and 2 with a little explanation inside the function itself.

def random_datetimes_or_dates(start, end, out_format="datetime", n=10): 

    '''   
    unix timestamp is in ns by default. 
    I divide the unix time value by 10**9 to make it seconds (or 24*60*60*10**9 to make it days).
    The corresponding unit variable is passed to the pd.to_datetime function. 
    Values for the (divide_by, unit) pair to select is defined by the out_format parameter.
    for 1 -> out_format="datetime"
    for 2 -> out_format=anything else
    '''
    (divide_by, unit) = (10**9, 's') if out_format=='datetime' else (24*60*60*10**9, 'D')

    start_u = start.value//divide_by
    end_u = end.value//divide_by

    return pd.to_datetime(np.random.randint(start_u, end_u, n), unit=unit)

Sample run:

random_datetimes_or_dates(start, end, out_format="datetime")

DatetimeIndex(['2017-01-30 05:14:27', '2016-10-18 21:17:16',
               '2016-10-20 08:38:02', '2015-09-02 00:03:08',
               '2015-06-04 02:38:12', '2016-02-19 05:22:01',


                  '2015-11-06 10:37:10', '2017-12-17 03:26:02',
                   '2017-11-20 06:51:32', '2016-01-02 02:48:03'],
                  dtype="datetime64[ns]", freq=None)

random_datetimes_or_dates(start, end, out_format="not datetime")

DatetimeIndex(['2017-05-10', '2017-12-31', '2017-11-10', '2015-05-02',
               '2016-04-11', '2015-11-27', '2015-03-29', '2017-05-21',
               '2015-05-11', '2017-02-08'],
              dtype="datetime64[ns]", freq=None)

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