/* varform.sas Daniel Brockman replace var names with x1, x2, ... */

/* contents:
1. numberoff. creates numbered set of variable names.
2. varform. rename data set vars to numbered names in new data set.
/*
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*/

%macro numberoff(varlist,xchar);
/* 
number off new X names.
new names are X1, X2, ... where X is one or more chars
specified in parameter xchar
This macro intended for call from macro varform
*/
%local i var;
%let i=0;
%do %while(%scan(&varlist,&i+1,%str()) ne %str());
  %let i = %eval(&i+1);
  %let var = %scan(&varlist,&i,%str());
  &var = &&xchar&i;
%end;            
%mend numberoff;

/*
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*/

%macro varform(inp,xset,xchar);
/* 
* renames variables in input data set inp to X1, X2, ... 
* in output data set xset, where X is one or more characters
* contained in parameter &xchar
* reference: http://support.sas.com/ctx/samples/index.jsp?sid=818
*/

%local i j varlist c3po ob2kinob xlist;

%put L40 inp:&inp xset:&xset xchar:&xchar ;  /* test */

/* put the names of the variables in a data set */
proc contents data=&inp
              noprint
              out=c3po
              varnum ;
run;

/* extract names of variables into macro var varlist */
data t1varform;
  set c3po;
  length ob2kinob $ 4096;
  retain ob2kinob;
  if (_N_=1) then ob2kinob=trim(name);
    else ob2kinob= trim(ob2kinob) || ' ' || trim(name) ;
  call symput('varlist',trim(ob2kinob));
run;

%put L57 varlist: &varlist ; /* test */

/* make output set */
data &xset ;
  set &inp. (rename=( 
    %let i=0;
    /* %do %while(%scan(&varlist,&i+1,%str()) ne %str()); */
    %do %while(%scan(&varlist,&i+1) ne );
      %let i = %eval(&i+1);
      %let var = %scan(&varlist,&i);
      &var = &xchar.&i          /* <--- write the rename line */
    %end;            
    ));
run;

%mend varform;

/*
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*/
;