st: Question on converting time-variable

[Simon Falck <sfalckstata@gmail.com>]

Dear Statalist,

Working with Stata 11.2, I want to convert two string variables (start, 
stop) with time information showing year-month-day-hour-minutes, e.g. 
"1998 10 19 1000" to time-format so "01oct1998 10:00:00", which can 
easily done by,

gen double starttime=clock(start, "YMDhm")
format starttime %tc

However, it appears that my timevariables (strings), i.e. the strings, 
sometimes indicate midnight as 2400, e.g. "2004 12 13 2400" and sometime 
as 0000, e.g. "1999 10 26 0000", and Stata seems only to accept the 
latter, implying that observations that indicate midnight as "2400" are 
not converted.

My question how to convert observations that indicate midnight as 2400 
to 0000 in the string variable(s), or to time variable(s)?

Thanks in advance,
Simon

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