IF THEN DO

[Deesee]

 if year = "2024" and wk1 = "wk53" then do; 
                                        wk1 = "wk01";  
                                        wk2 = "25_wk01"; 
 									   year = "2025"; 
 									   mth2 = "01"; 
 									   end; 

 if year = "2025" and wk1 = "wk00" then do; 
                                        wk1 = "wk01";  
                                        wk2 = "25_wk01"; 
 									   year = "2025"; 
 									   mth2 = "01"; 
 									   end; 
  
 if year = "2025" and wk1 = "wk01" then do; 
                                        wk1 = "wk02";  
                                        wk2 = "25_wk02"; 
 									   year = "2025"; 
 									   mth2 = "01"; 
 									   end; 

I get this after running the above:

How do I change the second row to be 25_wk01? Not sure what is wrong with the if then do statements if it produced this result after telling it exactly what to do.

data ip5;
 input  season_yr: $20.
        wbeg: DATE8.
        wend: DATE8.
	wk1: $4.
	wk2 $8.
	year $4.
	year3 $6.
	month3 $6. 
	month33 $3.
	mth2: $2.
	mth3: $6.
datalines;
Yr_24_25,29DEC24,04JAN25,24_wk53,Wk53,2024,2025,202501,JAN
Yr_24_25,29DEC24,04JAN25,25_wk00,Wk00,2025,2025,202501,JAN
Yr_24_25,05JAN25,11JAN25,25_wk01,Wk01,2025,2025,202501,JAN
;
run;

[Astounding · Accepted solution]

Not sure if this is a complete fix, but it's an issue that stands out.

If your first IF THEN finds a match:

if year = "2024" and wk1 = "wk53" then do; 
                                        wk1 = "wk01";  
                                        wk2 = "25_wk01"; 
 									   year = "2025"; 
 									   mth2 = "01"; 
 									   end; 

the program doesn't stop.  It keeps going through the remaining logic.  So the observation that meets the first set of conditions will automatically meet the third set of conditions:

if year = "2025" and wk1 = "wk01" then do; 
                                        wk1 = "wk02";  
                                        wk2 = "25_wk02"; 
 									   year = "2025"; 
 									   mth2 = "01"; 
 									   end; 

 If that's the issue, you will need to familiarize yourself with ELSE before an IF THEN.

[Deesee]

Thank you.  I did exactly what you did in those two if then do statements and got this result (*also did one other step beforehand to put wk00 into wk53 then pushed it to wk_01):

The frequencies look reasonable and the date ranges look fine but for some reason the second row is not showing as "25_wk01" but listed as "25_wk02".  The first and third rows are good.  I thought the "end" in the if then do stops it from looking further.  

  if year = "2025" and wk1 = "wk00" then do;  
    wk1 = "wk53";  
    wk2 = "24_wk53";  
    year = "2024";  
    mth2 = "12";  
  end;

if year = "2024" and wk1 = "wk53" then do;
                                       wk1 = "wk01"; 
                                       wk2 = "25_wk01";
									   year = "2025";
									   mth2 = "01";
									   end;
if year = "2025" and wk1 = "wk01" then do;
                                       wk1 = "wk02"; 
                                       wk2 = "25_wk02";
									   year = "2025";
									   mth2 = "01";
									   end;

[Deesee]

Ok I did the following and it looks like it worked with an else if statement, thank you!!

if year = "2024" and wk1 = "wk53" then do;
                                       wk1 = "wk01"; 
                                       wk2 = "25_wk01";
									   year = "2025";
									   mth2 = "01";
									   end;
else 

if year = "2025" and wk1 = "wk01" then do;
                                       wk1 = "wk02"; 
                                       wk2 = "25_wk02";
									   year = "2025";
									   mth2 = "01";
									   end;