Hi:

Here's one way to piece it together. All we need is the first variable, so
I'll manufacture a vector of Start.action's and go from there.

w <- data.frame(Start.action = c(rep('Start.setting', 3),
rep('Start.hauling', 4),
                                 rep('Start.setting', 4),
rep('Start.hauling', 6),
                                 rep('Start.setting', 4),
rep('Start.hauling', 4)))
wr <- rle(w$Start.action == 'Start.setting')
> wr
Run Length Encoding
  lengths: int [1:6] 3 4 4 6 4 4
  values : logi [1:6] TRUE FALSE TRUE FALSE TRUE FALSE

w$cycle <- rep(cumsum(wr$values), wr$lengths)
w$act <- ifelse(w$Start.action == 'Start.setting', 'set', 'haul')
w$action <- with(w, paste(act, cycle, sep = ''))
w$cycle <- w$act <- NULL
> w
    Start.action action
1  Start.setting   set1
2  Start.setting   set1
3  Start.setting   set1
4  Start.hauling  haul1
5  Start.hauling  haul1
<snip>
20 Start.setting   set3
21 Start.setting   set3
22 Start.hauling  haul3
23 Start.hauling  haul3
24 Start.hauling  haul3
25 Start.hauling  haul3

The rle() function is the key to this; given a logical statement as its
argument, it is TRUE for Start.setting and FALSE for Start.hauling. The
cumsum() function on the $values component of the result from rle() gives
the values we want, and we replicate them according to the vector of
$lengths given from rle. Once that is done, we just use a vectorized
ifelse() function to yield 'set' or 'haul' in a new variable and then piece
that together with the numeric vector...and we're done. Run the code one
line at a time to understand what each instruction is doing.

HTH,
Dennis

On Mon, Mar 7, 2011 at 7:13 PM, Darcy Webber <darcy.webber@gmail.com> wrote:

> Dear R users,
>
> I am working on allocating the rows within a dataframe into some
> factor levels.Consider the following dataframe:
>
>               Start.action                  Start.time
> 1            Start.setting    2010-12-30 17:58:00
> 2            Start.setting    2010-12-30 18:40:00
> 3            Start.setting    2010-12-31 22:39:00
> 4            Start.setting    2010-12-31 23:24:00
> 5            Start.setting    2011-01-01 00:30:00
> 6            Start.setting    2011-01-01 01:10:00
> 7            Start.hauling    2011-01-01 07:07:00
> 8            Start.hauling    2011-01-01 14:25:00
> 9            Start.hauling    2011-01-01 21:28:00
> 10          Start.hauling    2011-01-02 03:38:00
> 11          Start.hauling    2011-01-02 09:28:00
> 12          Start.hauling    2011-01-02 14:22:00
> 13          Start.setting    2011-01-02 20:51:00
> 14          Start.setting    2011-01-02 21:33:00
> 15          Start.setting    2011-01-02 22:47:00
> 16          Start.setting    2011-01-02 23:27:00
> 17          Start.setting    2011-01-03 00:35:00
> 18          Start.setting    2011-01-03 01:16:00
> 19          Start.hauling    2011-01-03 04:31:00
> 20          Start.hauling    2011-01-03 08:57:00
>
> I am trying to assign a factor level like the one below (named
> "action") according to the sequence of setting and hauling occuring in
> the "Start.action" column. In fact, it wouldnt even need to be a
> factor or character, it could simply be numbered (i.e., the set/haul
> prefix is useless as I could simply split it afterwards).
>
>              Start.action                   Start.time   action
> 1            Start.setting    2010-12-30 17:58:00    set1
> 2            Start.setting    2010-12-30 18:40:00    set1
> 3            Start.setting    2010-12-31 22:39:00    set1
> 4            Start.setting    2010-12-31 23:24:00    set1
> 5            Start.setting    2011-01-01 00:30:00    set1
> 6            Start.setting    2011-01-01 01:10:00    set1
> 7            Start.hauling    2011-01-01 07:07:00   haul1
> 8            Start.hauling    2011-01-01 14:25:00   haul1
> 9            Start.hauling    2011-01-01 21:28:00   haul1
> 10          Start.hauling    2011-01-02 03:38:00   haul1
> 11          Start.hauling    2011-01-02 09:28:00   haul1
> 12          Start.hauling    2011-01-02 14:22:00   haul1
> 13          Start.setting    2011-01-02 20:51:00    set2
> 14          Start.setting    2011-01-02 21:33:00    set2
> 15          Start.setting    2011-01-02 22:47:00    set2
> 16          Start.setting    2011-01-02 23:27:00    set2
> 17          Start.setting    2011-01-03 00:35:00    set2
> 18          Start.setting    2011-01-03 01:16:00    set2
> 19          Start.hauling    2011-01-03 04:31:00   haul2
> 20          Start.hauling    2011-01-03 08:57:00   haul2
>
> It seems like such a simple question, yet I just cant think of how to
> implement this. Any hints or ideas on how I might achieve this would
> be much appreciated.
>
> Regards,
> Darcy
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

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