Hi all!
I would like to duplicate a value within 1 individual. See below for my example.
In my example, I have multiple rows per individual, however only on 1 row contains a value for the Swabdate variable. I would like to duplicate this value to all rows within the individual.
How can I do this? Thank you so much!
Example:
Obs | study_id | swabdate |
1 | ~11001~ | . |
2 | ~11001~ | . |
3 | ~11001~ | . |
4 | ~11001~ | . |
5 | ~11001~ | . |
6 | ~11001~ | . |
7 | ~11001~ | . |
8 | ~11001~ | . |
9 | ~11001~ | . |
10 | ~11001~ | . |
11 | ~11001~ | . |
12 | ~11001~ | 09/08/2017 |
13 | ~11003~ | . |
14 | ~11003~ | . |
15 | ~11003~ | . |
16 | ~11003~ | . |
17 | ~11003~ | . |
18 | ~11003~ | . |
19 | ~11003~ | . |
20 | ~11003~ | . |
21 | ~11003~ | . |
22 | ~11003~ | 09/18/2017 |
23 | ~11005~ | . |
A datastep solution:
/* Assuming data is sorted by study_id */
data want;
do until(last.study_id);
set have; by study_id;
newdate = coalesce(newdate, swabdate);
end;
do until(last.study_id);
set have; by study_id;
output;
end;
format newdate mmddyy10.;
drop swabdate;
rename newdate=swabdate;
run;
Note: This pics up the first non-missing date encountered. To get the last date, use:
coalesce( swabdate, newdate).
A datastep solution:
/* Assuming data is sorted by study_id */
data want;
do until(last.study_id);
set have; by study_id;
newdate = coalesce(newdate, swabdate);
end;
do until(last.study_id);
set have; by study_id;
output;
end;
format newdate mmddyy10.;
drop swabdate;
rename newdate=swabdate;
run;
Note: This pics up the first non-missing date encountered. To get the last date, use:
coalesce( swabdate, newdate).
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