Date:         Thu, 13 Nov 1997 11:14:15 PST
Reply-To:     TWB2%Rates%FAR@bangate.pge.com
Sender:       "SAS(r) Discussion" <SAS-L@UGA.CC.UGA.EDU>
From:         Tim Berryhill 3rd time <TWB2%Rates%FAR@BANGATE.PGE.COM>
Subject:      Re: ? dynamically generating data
Comments: To: vlab@ECON.BERKELEY.EDU

One crude but effective solution would be to set the value back to missing after
the OUTPUT statement:
DATA TEST1;
  VAR1=1;OUTPUT;VAR1=.;
  VAR45=5;OUTPUT;VAR45=.;
RUN;
 
Tim Berryhill - Contract Programmer and General Wizard
TWB2@PGE.COM or http://www.aartwolf.com/twb.html
Frequently at Pacific Gas & Electric Co., San Francisco
The correlation coefficient between their views and
my postings is slightly less than 0
----------------------[Reply - Original Message]----------------------
 
Sent by:"Harish Chand" <vlab@ECON.BERKELEY.EDU>
 Dear SAS-L'ers,
 
I'm dynamically generating sas datastep statements from a web
application.  These statements are of the form:
 
        data test1;
        var1 = 1;       output;
        var45 = 5;      output;
 
In general, each observation might have a different set
of (non-missing) variables depending on what the user did on the web.
I would like to be able to specify only the non-missing variables and
have the rest set to missing. Unfortunately, sas is behaving as if
there were a retain statement.  If the variable is not created, the
previous value is used.  This is illustrated in the test code below.
 
Is there a simple fix (sas option) to this?  I would rather not have
to specify what the full set of variables might be ahead of time (as
this set is potentially very large, though with low probability).
 
Thanks,
Harish
 
*** Here is the test code ****
 
data test1;
 
var1=1; * var2 and var3 should be missing in this obs;
output;
 
var2=1; * var1 and var3 should be missing in this obs;
output;
 
var3=1; * var1 and var2 should be missing in this obs;
output;
 
proc print;
var var1-var3;
 
*** Unfortunately, this produces the following output instead: ****
 
                          OBS    VAR1    VAR2    VAR3
 
                           1       1       .       .
                           2       1       1       .
                           3       1       1       1
 
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