SAS : Find Variable with the Max or Min in a row

This tutorial demonstrates how to find a variable with the maximum or minimum value for each row (observation) in SAS. It's pretty straightforward to calculate max or min value but a little problematic to identify the variable name against the value.

Let's create Sample Data

data readin;
input y1-y6;
cards;
11 55 59 35 25 87
12 79 73 74 86 29
13 80 95 77 25 74
;
run;

Find Variable Name Containing Max Value in a row

data out;
set readin;
array values y1-y6;
largest = max(of values[*]);
index    = whichn(largest, of values[*]);
name = vname(values[index]);
proc print;
run;

Output

Use min() function instead of max() in the code above and the remaining code would be same.

Find Top 3 Variables

Suppose you are asked to identify top 3 variables across rows. You can use largest function in SAS.

LARGEST Function : Syntax

largest(k, variables)

k : kth value you want (2 for the second largest value)

data want;
   set readin;
   array values[*] y1-y6;
   array large[3];
   array names[3] $32;
   do i = 1 to dim(large);
      large[i] = largest(i,of values[*]);
      index    = whichn(large[i],of values[*]);
      names[i] = vname(values[index]);
   end;
   drop i index;
proc print;
run;

SAS : LARGEST values

Refer the code above and change largest() function to smallest() function.