Time difference

[ZoeyElle]

I have a list of datetimes and i need to perform count on it.
Only count as 1 if the current and previous time gap >=30 mins

Sample data:
9/8/2010 8:04:28 AM
9/8/2010 8:09:42 AM
9/8/2010 8:11:17 AM
9/8/2010 8:12:13 AM
9/8/2010 9:11:12 AM
9/8/2010 4:05:57 AM

What i need to do:
DateTime. Count. Logic
9/8/2010 8:04:28 AM Yes. 1st occurrence
9/8/2010 8:09:42 AM. No
9/8/2010 8:11:17 AM. No
9/8/2010 8:12:13 AM. No
9/8/2010 9:11:12 AM. Yes. Compare with 9/8/2010 8:04:28 AM
9/8/2010 4:05:57 AM. Yes. Compare with 9/8/2010 9:11:12 AM.

[Ksharp]

data temp;

 set temp;

 length count $ 3;

 retain _dt;

 count='no';

 if _n_ eq 1 then do;

                  
_dt=dt;

                  
count='yes';

                  

end;

 if dt - _dt
ge '00:30:00't then do;

                                    
_dt=dt;

                                    
count='yes';

                                  

end;

 drop _dt;

run;

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Ksharp


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