Condensing scattered data from same ID across multiple lines to one line with all data

[Caroline Hoch]

Hi all - I need help condensing scattered data from same ID across multiple lines to one line with all data. Here is an example of what I'm looking at:

ID	v1	v2
1	3	.
1	.	7
2	1	.
2	.	4
3	5	.
3	.	2

Thanks!

[Nick Cox]

clear
input ID    v1    v2
1    3    .
1    .    7
2    1    .
2    .    4
3    5    .
3    .    2
end 

collapse v1 v2, by(ID)

list 

     +--------------+
     | ID   v1   v2 |
     |--------------|
  1. |  1    3    7 |
  2. |  2    1    4 |
  3. |  3    5    2 |
     +--------------+

works for your example, as taking the mean over a single non-missing value yields just that value. But whether your real data are more complicated cannot be clear.

[George Ford]

tabstat v1 v2, by(ID)