topic Re: How to use "||" sign to get one new variable name? in SAS Procedures

How to use "||" sign to get one new variable name?

MikeTurner — Sun, 05 Feb 2012 12:13:28 GMT

I have one dataset including two(x y) or more variables. I want to do some transformation (for examle, power transformation) on my data and get a new dataset including x, y, trans_x and trans_y. Because I probably have more than two variables in my dataset, I wrote one macro.

%macro data_trans(inputdata, outputdata, varlist, trans_factor);

data &outputdata;

set &inputdata;

num=countw("&varlist");

do i=1 to num;

'tran_'||left(scan(&varlist,i))= (scan(&varlist,i))**&trans_factor; /* create one new variable name and do data transformation*/

end;

drop num i;

run;

%mend;

%macro data_trans(inputdata, outputdata, varlist, trans_factor);

data &outputdata;

set &inputdata;

array arr &varlist;

do over arr;

'trans_'||arr=arr**&trans_factor; /* create one new variable name and do data transformation*/

end;

run;

%mend;

Either of them didn't work. Something wrong was with "||".

Anyone could help me out with it? Greatly appreciated.

Re: How to use "||" sign to get one new variable name?

Tom — Sun, 05 Feb 2012 14:14:14 GMT

You need to use the macro statements to generate the variable names. Your code is trying to use DATA statements.

For example you want the macro to generate the text TRAN_VAR1 so that it can be used on the left side of an assignment statement.

%macro data_trans(inputdata, outputdata, varlist, trans_factor);
data &outputdata;
  set &inputdata;
%do i=1 %to %sysfunc(countw(&varlist));
  tran_%scan(&varlist,&i) = %scan(&varlist,&i)**&trans_factor;  
%end;
run;
%mend;

Re: How to use "||" sign to get one new variable name?

Linlin — Sun, 05 Feb 2012 16:52:21 GMT

assuming you want to transform all variables except variable 'aa':

data have;

input x y z aa;

cards;

1 2 2 20

3 4 3 30

;

%let trans_factor=2;

proc sql noprint;

select catt(name,',',name,'**',&trans_factor, ' as',catt(' trans_',name)) into: names separated by ','

from dictionary.columns

where libname='WORK' and memname='HAVE' and upcase(name) ne 'AA';

quit;

%put &names;

proc sql;

create table want as select &names

from have;

quit;

proc print;run;

Obs x trans_x y trans_y z trans_z

1 1 1 2 4 2 4

2 3 9 4 16 3 9

Linlin

Re: How to use "||" sign to get one new variable name?

MikeTurner — Thu, 09 Feb 2012 07:55:46 GMT

Thanks, all guys!