else if statement

[mona4u]

proc sort data=&Queries.2; BY STATUS Site_Number; RUN;
data &Queries.3;
set &Queries.2;
by status site_number;
if status="Open" and first.Site_Number then do; sitenum=0; end;
sitenum+1;
if status="Open" and last.Site_Number;

run;

I want to assign 0 for sitenum if status ne="Open"

I wasn't successful when I did it by else if statement 

Please advise me for the best way to do it  

[SuryaKiran]

if status="Open" and first.Site_Number then do; sitenum=0; end; <- This line will assign 0 
sitenum+1; if you don't have else here then it will change the value here

Try this:

proc sort data=&Queries.2; 
BY STATUS Site_Number; 
RUN;
data &Queries.3;
retain sitenum;
set &Queries.2;
by status site_number;
if status="Open" and first.Site_Number then sitenum=0;
else sitenum+1;
if status="Open" and last.Site_Number;

run;

[Tom]

You need to explain your logic.   

Why are you including FIRST.SITE_NUMBER if you only want to depend on STATUS?

An example for 2 or 3 sites with multiple records each would help explain your problem better.  Post simple sample data in the form of a data step.  Post what you expect the result to be.

[mona4u]

I need the compute the sitenum if status="Open" 

at the same time I need to assign 0 for sitenumb if status ne "Open"  

[Tom · Accepted solution]

---

@mona4u wrote:

I need the compute the sitenum if status="Open" 

at the same time I need to assign 0 for sitenumb if status ne "Open"  

---

Sounds like you need two variables.  One to "compute" and other that is what you actually want to output.

retain site_counter 0 ;
if status='OPEN' then do;
   site_counter+1;
   sitenum = site_counter;
end;
else sitenum=0;