Talk:Date manipulation

Task is Region specific

I live in the UK and tried the Tcl example: <lang tcl>loading history file ... 29 events added buffer line limit: 512 max line length: unlimited Main console display active (Tcl8.5.7 / Tk8.5.7) (HP DV8025EA) 30 % set date "March 7 2009 7:30pm EST" March 7 2009 7:30pm EST (HP DV8025EA) 31 % set epoch [clock scan $date -format "%B %d %Y %I:%M%p %z"] 1236472200 (HP DV8025EA) 32 % set later [clock add $epoch 12 hours] 1236515400 (HP DV8025EA) 33 % puts [clock format $later] Sun Mar 08 12:30:00 GMT 2009 (HP DV8025EA) 34 % </lang> As you can see, this is different from the answer given in the article.

How about making the task work for any region? --Paddy3118 03:15, 14 May 2009 (UTC)

Better yet, use Date or Time objects. --IanO

The task itself does not specify what the answer should be -- only the answers may/will be region specific. The result of the Tcl solution merely happens to show that I live in the Eastern time zone. --glennj 10:36, 14 May 2009 (UTC)

You can always use the -timezone option to print in another format.

<lang tcl>% set date "March 7 2009 7:30pm EST"

March 7 2009 7:30pm EST % set epoch [clock scan $date -format "%B %d %Y %I:%M%p %z"] 1236472200 % set later [clock add $epoch 12 hours] 1236515400 % clock format $later Sun Mar 08 12:30:00 GMT 2009 % clock format $later -timezone America/New_York Sun Mar 08 08:30:00 EDT 2009 % clock format $epoch Sun Mar 08 00:30:00 GMT 2009</lang>

The last one is just to check that it really is doing the time math right. Forgot that there was a DST change at that point in time... —Dkf 10:58, 14 May 2009 (UTC)