Hi all,
I have four variables that are coded as 0/1, and want to write if-then statements to produce a new variable if two or more of the variables =1. I could write out every feasible combination of the variables, but I'm certain there must be a more efficient and elegant way than:
if (var1=1 and var2=1 and var3=0 and var4=0) or (var1=1 and var2=0 and var3=1 and var4=0) or...... and so on
then newvar=1
But I'm a fairly new with SAS and not sure how to approach differently. Any insight would be appreciated. Thanks!
How about a simple sum
data want ;
/* set up test data */
do var1=0 to 1 ;
do var2=0 to 1 ;
do var3=0 to 1 ;
do var4=0 to 1 ;
/* code to set newvar if 2 or more var1-4 are set to 1 */
x=sum(var1,var2,var3,var4) ;
if x>1 then
newvar=1 ;
else
newvar=0 ;
/* output all variables to dataset */
output ;
/* end do loops for test data */
end ;
end ;
end ;
end ;
run ;
How about a simple sum
data want ;
/* set up test data */
do var1=0 to 1 ;
do var2=0 to 1 ;
do var3=0 to 1 ;
do var4=0 to 1 ;
/* code to set newvar if 2 or more var1-4 are set to 1 */
x=sum(var1,var2,var3,var4) ;
if x>1 then
newvar=1 ;
else
newvar=0 ;
/* output all variables to dataset */
output ;
/* end do loops for test data */
end ;
end ;
end ;
end ;
run ;
NewVar = sum(of var1-var4) > 1;
Condensing @AMSAS solution somewhat you can use the above as an example. Exactly how you list the variables in the SUM() can vary a few ways, from explicitly listing them to shortcut lists.
Here is a reference that illustrates how to refer to variables and datasets in a short cut list:
https://blogs.sas.com/content/iml/2018/05/29/6-easy-ways-to-specify-a-list-of-variables-in-sas.html
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