st: Distorted time when building SIFs from components

[Milena Przheska <milena.przheska@cosmicdevelopment.com>]

Dear Statalist members,

I have a dateime variable 'time' with format %tc and a 'date' variable
with only the date. I needed a variable that will show the date and
the hour, so that observations happening on the same date in the same
hour would have same time stamp. Therefore, I first extracted the
year, month and day from 'date' and hour from 'time'. Then I generated
two separate variables with values 0, to serve as minutes and seconds.
Finally, I build a time stamp from these components, but instead of
getting datetime variable with zero minutes and seconds, I got a
variable that had altered hour, minutes and second.

Can anyone please let me know why this happens and how can I fix it?

Commands:

gen double date = dofc(time)
format date %td

gen double Y = year(date)

gen double M = month(date)

gen double D = day(date)

gen double h = hh(time)

gen double m = 0

gen double s = 0

gen short_time = mdyhms(M, D, Y, h, m, s)
format short_time %tc


Results:

m    s    h      Y      M    D     short_time
0    0    18    2013    5    22    22may2013 17:59:21
0    0    14    2013    5    26    26may2013 13:59:40
0    0    6     2013    5    4     04may2013 05:58:58
0    0    20    2013    5    9     09may2013 20:00:14
0    0    2     2013    6    5     05jun2013 01:59:13
0    0    6     2013    7    8     08jul2013 05:59:40
0    0    6     2013    7    8     08jul2013 05:59:40


I would appreciate your help.

Thank you,
Milena
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