Change values of the first variable based on values of the second variable

[Lijuu]

Hi Everyone!

How can i rename "A" in var1 into A1, A2 and A3 based on 1, 8, and 25 in var2?

i.e lets have:

var1  var2

A         1

A         8

A         25

B          3

c          5

A          1

A          8

A         25

into  

var1  var2

A1        1

A 2       8

A 3       25

B           3

c           5

A1         1

A 2        8

A 3       25

Thank you alot!

[ballardw · Accepted solution]

Not "renaming" that means something else in SAS regardless of how you use your variable var1.

One of the basic approaches to changing the value of a variable based on the value of a different variable is the IF /Then statement in a data step:

data want;

   set have;

   If var1='A' and var2=1 then var1='A1';

run;

Some potential gotchas exist with this though. The variable var1 will have a length associated with the variable. If the length is 1 (one) then attempting to add more characters at the end will fail as there is no room for the additional variable.

You can group similar values into a "DO block to avoid repeating some tests such as var1='A': The following code demonstrates that plus how to change the length of var1 if needed.

data want;
   length var1 $ 5;
   set have;
   If var1='A' then do;
      if var2=1 then var1='A1';
      if var2=8 then var1='A2';
      if var2=25 then var1='A3';
   end;
run;

[Lijuu]

Thank you much in advance!!