/*
Here is an example where we can use an ARRAY statement to substitute values for missing;
*/
*First we read in a test data set for you;
data mydata;
 input Y VAR1 VAR2 VAR3;
cards;
1	10	33	4
0	20	21	3
1	30	59	2
1	20	76	1
0	.	24	3
0	20	.	2
1	10	28	2
1	10	49	2
0	30	76	.
1	20	59	2
;

*By using the _numeric_ command, you can automatically tell SAS to only do this ;
*for numeric variables;
data test (drop=i);                                                    
set mydata;                                                            
array MISSING(*) _numeric_;                                            
do i = 1 to dim(missing);                                              
   if missing(i)=. then missing(i)=-9999;                                    
end;                                                                    
run;                                                                    

Title QUICKLY SUBSTITUTING A VALUE FOR MISSING;
proc print data=test;run;