Replace values from two variables into one

[drfzLee]

Hello Community,

Question from a noob.

I have two variables that need to be compared. Variable x is the old variable and variable y the new one. 
The values in variable x partly have a leading zero and a different date format than the values in variable y. Other values may be ok. 
I created two new variables. Varnew1 holds all formatted  values with a leading zero. Varnew2 holds all formatted new date values. I used tranwrd. 
Is it now possible to replace the new values into Var x so that i can compare var x and var y?
Example:

Var x                                Var y             Varnew1              Varnew2

1                                      1                        

30

05                                    5                         5 

2017-09-14                     21076                                         21076

...

[s_lassen · Accepted solution]

Something like this?

data have;
  length Var_X Var_Y $10;
  input Var_X Var_Y;
cards;
1 1          
30 .
05 5           
2017-09-14 21076 
;run;

options datestyle=ymd;
data want;
  set have;
  length Varnew1 Varnew2 $10;
  if Var_X ne '' and Var_Y ne '' and Var_X ne Var_Y then do;
    if input(Var_Y,10.)=input(Var_X,?? anydtdte10.) then
      Varnew2=Var_Y;
    else if input(Var_Y,10.)=input(Var_X,10.) then
      Varnew1=Var_Y;
    end;
run;

I added the OPTIONS DATESTYLE=YMD because some dates, e.g. 2017-09-08 can be ambigous.