[S] A subsetting question.

["Calvin L. Williams, Ph.D." <calvinw@math.clemson.edu>]

S-Plus users,

This is perhaps a simple question whose answer may lie deep
in the S-Plus archive somewhere, but  can some one tell me how
to subset data of the form

patient sex visit
1 1 1
1 1 2
...
1 1 10
2 1 1
...
2 1 5
3 1 1
3 1 2
4 1 1
4 1 2
4 1 3
...

... so that my subset only has those paitients with 3 or more visits?

Thanks,
Calvin

====================  Calvin L. Williams  =========================
     Department of Mathematical Sciences, Clemson University
       0-323 Martin Hall Clemson, South Carolina 29634-1907
      VOICE: (864) 656-5241  or leave message (864) 654-7187
                 EMAIL: calvinw@math.clemson.edu
                               FAX: 1-(864) 656-5230
        WWW:   http://www.math.clemson.edu/~calvinw/
============================================================


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