Date:         Fri, 14 Jan 2005 17:29:27 -0500
Reply-To:     "Chang Y. Chung" <chang_y_chung@HOTMAIL.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         "Chang Y. Chung" <chang_y_chung@HOTMAIL.COM>
Subject:      Data Step View. Was(Re: Dynamic method to change numeric and
              character missing value)

Hi,

About the data step views... Once you get used to the idea of a data step
view, the natural next question is "can I parameterize it?" For example, the
following view converts character missing values to "?"'s only for the data
set, one.

/* test data */
data one;
  set sashelp.class;
  /* make some missings */
  if _n_ <= 3 then do;
    sex = "";
    age = .;
    height = .;
  end;
run;

/* a data step view with a hard coded input data set name */
data missQ / view=missQ;
  set one;
  array chars _character_;
  do over chars;
    if missing(chars) then
      chars = repeat('?', 32767-1);
  end;
run;


So, instead of hard coding the dataset name, we can try to put the data set
name with a macro variable, instead. like:

data missQ / view=missQ;
  set &data;   /* <-- changed */
  array chars _character_;
  do over chars;
    if missing(chars) then
      chars = repeat('?', 32767-1);
  end;
run;

So that we can later use this view like:

%let data=one;
proc print data=missQ;
run;

Or if we had a data set two, then
%let data=two;
proc print data=missQ;
run;

Well, good idea -- I thought initially. However, it turned out that the new
view (with "&data") does not compile! :-(


So, here is the open question: Can we "parameterize" data step view at all,
or not?!

I have a partial answer and am hoping someone could share a more complete
answer with us.

I would like to direct this question to specially for those who took and
passed the base certification exam!!

(hint: http://support.sas.com/certify/samples.html)

Happy Friday!

Cheers,
Chang