SAS macro %if %then %else problem

[y_fu]

I am writing a macro to create a 2x2 table and calculate sensitivity/specificity/ etc. A part of the macro is not working well, and I have no idea why. The code does not have any error message, but seems it only import the set &data, but not do anything about the %if %then result. Here is part of the code:

%MACRO tabulate(data, target, comp);

   /* ................datalines........................ */

  data data1 (replace=yes);

           set &data;

          %if "&comp._&target._result"="Positive" and "V_&target._result"="Positive" %then result="TP";

          %else %if "&comp._&target._result"="Positive" and "V_&target._result"="Negative" %then result="FN";

           %else %if "&comp._&target._result"="Negative" and "V_&target._result"="Positive" %then result="FP";

           %else %if "&comp._&target._result"="Negative" and "V_&target._result"="Negative" %then result="TN";

     run;

/*................ more data ............*/

%MEND;

I also tried to use %then %put result = "TP", still not working. This part of the code should give me a new column with name "result", and have "TP" "FN" "FP" "TN" in the column.

I can run this in the main program, but when I put this into a macro, it does not work.

Thank you if you can give me some advice.

[Astounding]

DATA steps can't execute macro statements.  Just get rid of all the percent signs and you should be fine.  (Leave the ampersands in place, only the percent signs need to go.)

[AndrewHowell · Accepted solution]

Macro code is scanned & executed before data step code is scanned & executed.

It might be simpler to maintain if you separate the macro & data step code:

%MACRO tabulate(data, target, comp);

  /* ................datalines........................ */

%local result;
%if  &comp._&target._result=Positive and V_&target._result=Positive %then %let result=TP;
%else %if &comp._&target._result=Positive and V_&target._result=Negative %then result=FN;
%else %if &comp._&target._result=Negative and V_&target._result=Positive %then result=FP;
%else %if &comp._&target._result=Negative and V_&target._result=Negative %then result=TN;

  data data1 (replace=yes);
          set &data;
          result="&result";
  run;
 
/*................ more data ............*/

%MEND;

[Reeza]

http://support.sas.com/kb/24/170.html