do sth only if conditions in the next row are met

[opiczak]

Hello,

I will try it as simply as possible at first...

I have this dataset:

group   n_animals  age_difference

1          8                 1                        

2          45               2                     

4          19               1

And I would like to programme this: if group=1 and n_animals<30 then create variable g2 as group+1 “but only when the next group (group=1+1) has age difference < 2”.

The part in quotes is something I cannot figure out. I would really appreciate if the syntax stayed this way so I do not have to start from scratch.

[WarrenKuhfeld · Accepted solution]

Look up the POINT= option on the SET statement. You can have one SET statement (with the POINT= option) that reads ahead and one ordinary SET statement that reads the current row to process. There are other ways too. Be sure to not use POINT= to try to read beyond the data.

[opiczak]

Thank you, Warren. I quickly went through some guide and I am pretty sure this can solve my problem. Have a nice day.

[Ksharp]

Assuming I understand your question.

data have;
input group   n_animals  age_difference;
cards;
1          8                 1                        
2          45               2                     
4          19               1
;


data want;
merge have have(keep=age_difference rename=(age_difference=_age_difference) firstobs=2);
if group=1 and n_animals<30 and  _age_difference< 2 then g2=group+1;
drop _age_difference;
run;

[opiczak]

Thank you very much! I think this can work. I would like to mark your reply as a solution, but apparently there can be only one (?). So I hope you do not mind.

[Ksharp]

I do not mind and do not care . 🙂