Date:         Thu, 18 Jul 1996 11:24:00 CET
Reply-To:     gio <ferro@UNI2A.UNIGE.CH>
Sender:       "SAS(r) Discussion" <SAS-L@UGA.CC.UGA.EDU>
From:         gio <ferro@UNI2A.UNIGE.CH>
Organization: only when absolutely necessary
Subject:      %scan and counting # of delimiters ? a macro question

I have a simple macro which I would like to improve (but can't).
The purpose of the macro is to delete missing observations of relevant
variables in a dataset which are needed for further use in PROC IML.
The variables are stored in a macro, say;
%macro myvars;
educ married sex income
%mend myvars;
(Well, the `%let myvars=...' form could also be used, I suppose)
I've written the following macro which does a nice job:
%macro clean(varlist,n);
  %do i=1 %to &n;
      if %scan(&varlist,&i,%str( ))=. then delete;
  %end;
%mend clean;
The ugly part is that I have to specify myself the number of
variables stored in the macro, and it can be tedious to trace it and
count them.
So my question is: how can I let SAS determine the number of variables
in the macro which is then %scanned ?
Can the number of delimiters (here single spaces) be stored somehow?
Thanks for any tip.
--Giovanni