Thank you very much Patrick. The problem is solved. Sure, I'll post a sample dataset for the next time.   Regards ... View more

Thnak you for your response. Actualy, I have such a dataset:   Obs STID Interval RELH TAIR WSPD SRAD Date Time Month Day Year Hour Minute 1 A 01JAN2015:00:00:00 58 -5.2 1.7 0 1/1/2015 0:00 1 1 2015 0 0 2 B 01JAN2015:00:00:00 58 -5.2 1.6 0 1/1/2015 0:05 1 1 2015 0 5 3 C 01JAN2015:00:00:00 58 -5.2 1.6 1               4 D 01JAN2015:00:00:00 58 -5.2 1.6 0               5 E 01JAN2015:00:00:00 58 -5.2 1.6 0               6 F 01JAN2015:00:00:00 58 -5.2 1.6                 7 G 01JAN2015:00:00:00 58 -5.2 1.6                 8 H 01JAN2015:00:00:00 58 -5.2 1.6                 9 I 01JAN2015:00:00:00 58 -5.2 1.6                 10 A 01JAN2015:00:05:00 60 -5.2                   11 B 01JAN2015:00:05:00 58 -5.2                   12 C 01JAN2015:00:05:00 58                     13 D 01JAN2015:00:05:00 60                     14 E 01JAN2015:00:05:00 40                     15 F 01JAN2015:00:05:00 58                     16 G 01JAN2015:00:05:00 66                     17 H 01JAN2015:00:05:00 30                     18 I 01JAN2015:00:05:00                         For each date and time (i.e., interval), we have 9 series of samples at 9 different stations (STID).  I need to create a new dataset including single and unique Intervals (date and time) with the avergae of each variable for the 9 "STID"s (STID should be removed). Exactly like this:   Obs Interval RELH_ave TAIR_ave WSPD_ave SRAD_ave Date Time Month Day Year Hour Minute 1 01JAN2015:00:00:00 58 -5.2 1.7 0 1/1/2015 0:00 1 1 2015 0 0 2 01JAN2015:00:05:00 60  6.7  2.0  0  1/1/2015  00:05 1 1 2015 0 5 3 01JAN2015:00:10:00  38 4.9  3.7  1.68  1/1/2015  00:10  1 1 2015 0 10   For each date and time (i.e., interval), I need to find the average of each variable for each time and date interval (i.e., Interval) to removre the impact of stations (STID). It'd be really appreciated if you can help.   Best Regards, Paalang      ... View more

Thank you very much. ... View more

Thank you very much for the info.   Regareds,   ... View more

Thank you very much. The problem's been solved. Could you please shade some ligh on the prev_srad temporary variable and how does the itteration is performed?   Thank you much. ... View more

Thank you guys very much. The problem's been solved.  ... View more

Thank you for the response. I got a time series dataset with 5 min resolution, and wanna spot the points at which solar radiation is suddenly decreased/increased by about %70. To do so, I want to compare the solar radiation quantities consecutively to spot the points of interest, and delete the rows at which this sudden increase/decrease doesn't happen. I think the code should look forward.   Comparing the rows like this and set new variable "x" to 1 if the if statement is satisfied, o.w. x=0. Then, I can delete the rows with x=0. if SRAD(i+1)<0.3*SRAD(i) then x=1;   Thank you,   ... View more

Thank you for your response. But this informat does not work with the following piece of code:   data diss.rawdata (drop=fname); length myfilename $100; length name $25; set diss.dirlist; informat Interval E8601DT16.;   filepath = "&dirname\"||fname; infile dummy filevar = filepath length=reclen end=done FIRSTOBS=2 /*obs=4*/ missover dsd; do while(not done); myfilename = filepath;   input STID $ Interval : $16. RELH TAIR WSPD WVEC TA9M WS2M; format Interval datetime22.;   Date=datepart(Interval); Time=timepart(Interval); output; end;   drop myfilename name; *format Date MMDDYY10. Time hhmm.; run; ... View more