topic how to create new variables based on information from old variables? in SAS Procedures

how to create new variables based on information from old variables?

littlestone — Tue, 06 Sep 2011 16:23:45 GMT

Suppose I have following codes:

data new;

set old;

array old_var_array

_CHARACTER_;

..................(codes to be inserted)

..................

Based on number of character variables ( which can be obtained using dim(old_var_array) in the above example), I want to create equal number of new variables (NewVar1-NewVar#ofChar). How can I do this? thanks.

how to create new variables based on information from old variables?

art297 — Tue, 06 Sep 2011 16:42:01 GMT

Take a look at the method I suggested in a post the other day:

http://communities.sas.com/message/104323#104323

how to create new variables based on information from old variables?

littlestone — Tue, 06 Sep 2011 18:44:56 GMT

Thank you very much.The code you gave to me works perfectly for me

By the way, I find another way that can also do the job. Here is the code (I am not sure if this method is considered professional or not):

data _Null_;

set old;

array stringvar

_CHARACTER_;

NumofCVar = dim(stringvar) ;

call SYMPUTX('NumOfCVar',NumOfCVar);

run;

data new;

set old;

array old_var_array

_CHARACTER_;

array _NewVar[&NumofCVar] NewVar1-NewVar&NumofCVar;

..............

how to create new variables based on information from old variables?

art297 — Tue, 06 Sep 2011 18:54:55 GMT

Looks almost sufficiently professional enough to me for whatever that is worth. However, I would simplify the first step so that you don't read through all of the records. e.g.:

data _Null_;

set have;

if _n_ eq 1 then do;

array stringvar

_CHARACTER_;

NumofCVar = dim(stringvar) ;

call SYMPUTX('NumOfCVar',NumOfCVar);

end;

stop;

run;

how to create new variables based on information from old variables?

littlestone — Tue, 06 Sep 2011 20:40:30 GMT

thanks a lot for suggestion

how to create new variables based on information from old variables?

Ksharp — Wed, 07 Sep 2011 02:45:38 GMT

dictionary tables already contains the number of character variables.

proc sql ;

select num_character

from dictionary.tables

where libname='SASHELP' and memname='CLASS';

quit;

Ksharp

how to create new variables based on information from old variables?

littlestone — Wed, 07 Sep 2011 14:44:11 GMT

thank you Ksharp. I actually didn't know there exists "dictionary tables". It is such a wonderful tool.