Hi everyone!   I'm using the SAS sample data set called stress99.   data sasuser.stress99; input ID $ 1-4 Name $ 7-18 RestHR 25-26 MaxHR 32-34 RecHR 39-41 TimeMin 48-49 TimeSec 57-58 Tolerance $ 65 Year 70-73; datalines; 2501 Bonaventure, T 78 177 139 11 13 I 1999 2544 Jones, M 79 187 136 12 26 N 1999 2552 Reberson, P 69 158 139 15 41 D 1999 2568 Eberhardt, S 72 182 122 16 49 N 1999 2571 Nunnelly, A 65 181 141 15 2 I 1999 2578 Cameron, L 75 158 108 14 27 I 1999 2579 Underwood, K 72 165 127 13 19 S 1999 2588 Ivan, H 70 182 126 15 41 N 1999 2595 Warren, C 77 170 136 12 10 S 1999 ;   Now what I would like to do is to create a data set that holds only the smallest value for TimeMin, which would be TimeMin=11.   I tried:   proc sort data = sasuser.stress99; by timemin; run; data bla (drop = resthr maxhr rechr tolerance timesec year); set sasuser.stress99; by timemin; first_time= first.timemin; if first.timemin; run; But what it will give me is the first UNIQUE value for TimeMin. Where am I going wrong?  I found this solution and I don't see why it works in their example but not in mine.    Thank you! ... View more

Hi!   So I have this problem (using sas universtiy): I am supposed to merge datasets that have two common variables (id and weight) and look for values that are different for one variable (weight).  Say: Data sheet1; input id weight1; datalines; 1 33 2 44 3 55 4 66 5 77 ; run; Data sheet2; input id weight2; datalines; 1 11 2 44 3 55 4 66 5 88 ;  run;  To identify observations 1 and 5 I would run;   Data differences; merge sheet1 sheet2; by id; run; Data differences; set differences; where weight1 ne weight2; run; Provided  they're propperly sorted.   But I am supposed to run this code:     Data differences; merge sheet1 sheet2 (in =a); by id weight; if a; run; And I just don't understand how that's supposed to work. The way I understand it is that the datasets are merged by id and weight for all observations in a and  overwriting values that are different with those from sheet2.  Maybe I'm not thinking of the right data structure. My supervisor tried to explain it to me, saying that the merge statement would create missings for values that aren't equal on both datasets.    Can someone fill me in? Thanks's in advance!      ... View more