st: Automating calculating durations from beginning and end dates

[Clare L Maxwell <maxwellcl1@earthlink.net>]

Hello to the programmers of Statalist.

I have some beginning and end treatment dates, and I would like to 
calculate durations of treatment.

beginning date vars:  cb01dt cb02dt cb03dt cb04dt cb05dt
ending date vars:     ce01dt ce02dt ce03dt ce04dt ce05dt
duration vars:        cdur01 cdur02 cdur03 cdur04 cdur05

Some of the data:

       id       cb01dt       cb02dt       ce01dt       ce02dt
     E014   04/21/1997   04/30/1997   04/30/1997   04/30/1997
     E044   03/17/1998   04/01/1998   04/01/1998   04/01/1998
     E046   04/22/1998   04/27/1998   05/07/1998   04/27/1998
     E055   08/28/1998   09/04/1998   09/11/1998   09/04/1998
     E068   11/06/2000   11/08/2000   11/08/2000   11/20/2000
     H006   10/27/1998   11/05/1998   10/30/1998   11/18/1998
     M008   08/21/1999   08/19/1999   08/30/1999   08/19/1999
     M009   09/17/1999   09/20/1999   09/20/1999   10/03/1999
    UW041   04/21/1999   04/21/1999   04/30/1999   04/30/1999
    UW046   08/10/1999   08/10/1999   08/19/1999            .
    UW047   08/26/1999   08/28/1999   09/05/1999   09/05/1999

The duration of the 1st treatment, cdur01, for E014 is from 4/21/97 
to 4/30/97 = 10 days, for example.

I suspect I should use forvalues 1 to 5 to do all the calculations at 
once, but I am not sure how to proceed.  Would you be able to help 
with this programming task?

Thank you very much.  I have really appreciated your help with 
previous related problems.  I look forward to learning a lot more 
from this one.

				Yours truly,
				Clare Maxwell
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