i am wondering if we can ignore a variable in a statement if it doesnt exist and continue with the data step.   data mgh;    set ae;   if strip(aecon)="" and strip(acn)="" and strip(withd)="" then ae_use="";  else if aecon="N" and strip(upcase(acn)) run;   in some datasets i do not have aecon variable and when i run with them it gives error. can i do something which makes it run without error if the aecon variable is missing and the rest of the program runs as usual.   any suggestions ... View more

i have the below data: subj asdt svsstd_num flag 101 2006-01-10 28-dec-05 Y 102 2005-11-15 12OCT2005 Y 102 2005-12-08 07-nov-05 Y 103 2006-01-05 02-dec-05 Y the svsstd_num date format ias 12OCT2005 however i am not able to make it in excel. but all the date in  svsstd_num is the same format.   I am using the below code; data ae051; set ae98; svsstd_num=input(SVSTDTC,yymmdd10.); format svsstd_num date9.; if visit="Visit 2 (Baseline)" then do; if ASTDT < svsstd_num then flag= "N"; else flag= "Y"; end; run; which is taking if visit is in visit2 then flag, but if we see the second observation the flag should be "N". I am not sure why it is not giving the right result.   ... View more