Dear All, Suppose that I use -stack- command in the following.
Code:
 webuse stackxmpl, clear

. list

     +---------------+
     | a   b   c   d |
     |---------------|
  1. | 1   2   3   4 |
  2. | 5   6   7   8 |
     +---------------+

.         
. stack a b c d, into(e f) clear

. list

     +----------------+
     | _stack   e   f |
     |----------------|
  1. |      1   1   2 |
  2. |      1   5   6 |
  3. |      2   3   4 |
  4. |      2   7   8 |
     +----------------+
My question is: how can go from the bottom table to the top table? Thanks.