st: Keeping the Earliest Observations on Each Leg

["Raphael Fraser" <raphael.fraser@gmail.com>]

I  am interested in keeping the earliest observations on each leg
where  left leg is denoted (lleg=1) and right leg (lleg=0). Can anyone
assist?

     id         date   lleg
      46   22aug1993      0
      46   28sep1993      1
      46   28sep1993      1
      46   28sep1993      0
      46   28sep1993      0
      46   03feb1998      1
      46   12mar2001      1
      55   10mar1995      0
      55   19oct1999      0
      57   23aug1991      1
      57   30aug1993      1
      57   28feb1996      1
      57   23sep2002      0
      57   23sep2002      0
     166   15aug1995      1
     166   19jun1996      0
     166   19jun1996      0
     166   07jan1999      1
     166   22mar1999      0
     198   25jul1990      1
     198   10sep1991      1
     269   18oct1995      0
     269   29apr1996      1
     269   26sep1996      0
     269   06nov1996      1

Raphael
*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/