Compute sleep time

* To compute the number of hours of sleep (the date is not available from the data).
* Raynald Levesque.

NEW FILE.
DATA LIST LIST /id(F8) Sleetime(TIME5) sampm(A2) waketime(TIME5) wampm(A2).
BEGIN DATA.
1 12:00 PM 11:00 AM 
2 2:00 AM 10:00 AM
3 4:00 AM 1:00 PM
4 11:30 PM 12:30 PM
5 12:30 AM 12:45 PM
END DATA.
LIST.

* I assume sleep time of half past midnight is coded as 12:30 AM.
COMPUTE  timebeg=12+sleetime/3600.
IF sampm='AM' AND (XDATE.HOUR(sleetime)<>12) timebeg=timebeg+12.
COMPUTE  timeend=24+waketime/3600.
IF wampm='PM' AND (XDATE.HOUR(waketime)<>12) timeend=timeend+12.
COMPUTE dur1=timeend-timebeg.
* Here dur1 is a real number (10.25 means 10 hours 15 minutes)
* if you want answer in HH:MM format.
COMPUTE dur2=dur1*3600.
FORMATS dur2(TIME5).
EXECUTE.


NEW FILE.
DATA LIST LIST /id(F8) Sleetime(DTIME8) waketime(DTIME8).
BEGIN DATA.
1 1:00:00 1:11:00 
2 1:2:00 1:10:00
3 1:4:00 1:1:00
4 0:11:30 1:12:30
5 1:00:30 1:12:45 
END DATA.
LIST.

* version 2.
* Here time is entered in DTIME format, in this format.
* 0 21:00 means 9 PM the day before the survey.
* 1 00:30 means half past midnight.
* 1 01:00 means 1 AM the day of the survey.
* 1 12:30 means 12:30 PM the day of the survey.

COMPUTE dur3=dwtime-dstime.
FORMAT dur3 (TIME5).
*Here dur3 is duration in hours and minutes (10:30 is 10 hours and 30 minutes).
EXECUTE.