Reshaping data in R with “login” “logout” times

Question

I\'m new to R, and am working on a side project for my own purposes. I have this data (reproducable dput of this is at the end of the question):

     X              


        

Answer 1

Using rowid() from the data.table-package along with dcast:

require(data.table)
dcast(dt, user + rowid(user, state) ~ state, value.var="datetime")

#      user user_1              joined                left
#  1: User1      1 2016-02-19 19:13:26 2016-02-19 19:13:32
#  2: User1      2 2016-02-19 19:21:33 2016-02-19 19:25:26
#  3: User1      3 2016-02-19 19:35:38 2016-02-19 19:42:16
#  4: User1      4 2016-02-19 19:44:15 2016-02-19 19:47:59
#  5: User1      5 2016-02-19 19:48:55 2016-02-19 19:51:06
#  6: User1      6 2016-02-19 19:52:40                
#  7: User2      1 2016-02-19 19:21:18 2016-02-19 19:30:30
#  8: User3      1 2016-02-19 19:53:15 2016-02-19 20:02:26
#  9: User3      2 2016-02-19 20:02:34                
# 10: User3      3 2016-02-19 20:13:48