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Kevin:
Thanks for your suggestion. I did use floor() function after getting your email and you're right, there is a difference in the age.
Thanks for the suggestion. But I have a question in regards to the difference (and it maybe a naïve question) but would you know why the difference occurs?
Thanks
Kumar
-----Original Message-----
From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of Kevin Roland Viel
Sent: Tuesday, May 24, 2005 10:32 AM
To: SAS-L@LISTSERV.UGA.EDU
Subject: Re: Question on Proc SQL
> int((consdtn-birthdtn)/365.25) as age
Kumar,
This does not always return the age you might expect. I suggest the
YRDIF() function, for instance. Also, why not just use the FLOOR()
function, since you expect age to be positive anyway?
Consider:
993 data _null_ ;
994
995 /* AGE = 1 , born in non-leap year */
996 birthdtn = mdy( 01 , 01 , 2003 ) ;
997 consdtn = mdy( 01 , 01 , 2004 ) ;
998
999 diff = intck( "DAYS" , birthdtn , consdtn ) ;
1000
1001 d1 = int((consdtn-birthdtn)/365.25) ;
1002 d2 = floor( yrdif( birthdtn , consdtn , "actual" )) ;
1003
1004 put birthdtn= mmddyy10. consdtn= mmddyy10. ;
1005 put diff= d1= d2= / ;
1006
1007 /* Year - 1981 = 5 , 10 , 15 , 20 (why 20?),... */
1008 birthdtn = mdy( 01 , 01 , 1981 ) ;
1009 consdtn = mdy( 01 , 01 , 1986 ) ;
1010
1011 diff = intck( "DAYS" , birthdtn , consdtn ) ;
1012
1013 d1 = int((consdtn-birthdtn)/365.25) ;
1014 d2 = floor( yrdif( birthdtn , consdtn , "actual" )) ;
1015
1016 put birthdtn= mmddyy10. consdtn= mmddyy10. ;
1017 put diff= d1= d2= / ;
1018
1019 run ;
birthdtn=01/01/2003 consdtn=01/01/2004
diff=365 d1=0 d2=1
birthdtn=01/01/1981 consdtn=01/01/1986
diff=1826 d1=4 d2=5
NOTE: DATA statement used (Total process time):
real time 0.01 seconds
cpu time 0.01 seconds
Regards,
Kevin
Kevin Viel
Department of Epidemiology
Rollins School of Public Health
Emory University
Atlanta, GA 30322
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