Removing
On Mar 12, 2009, at 3:02 PM, David Winsemius wrote:
True, I suppose. The specification from Ma could have been more
explicit. Should she want to only have duplicates in sequence, then
perhaps the use of construction within the rle function would be
useful.
act2[ act2$Rep[-1] != act2$Rep[-length(act2$Rep)], ]
Date Dtime Hour Min Second Rep
51 2006-02-22 14:52:18 14 52 18 useractivity_act
57 2006-02-22 14:52:51 14 52 51 4
58 2006-02-22 14:52:52 14 52 52 3
60 2006-02-22 14:54:42 14 54 42 useractivity_idle
Which turns out on examination to be isomorphic to Gabor's earlier
efforts.
Almost ... but not quite. The addition of a TRUE to that logical vecor (as in Bill Dunap's posting as well as Gabor's solution) is needed to keep this from failing in some instances, although this test case did not expose the flaw. act2[c(TRUE, act2$Rep[-1] != act2$Rep[-length(act2$Rep)]), ]
-- David Winsemius On Mar 12, 2009, at 2:31 PM, Patrick Burns wrote:
Simpler, but maybe wrong. Not duplicated was my first response as well, but then I began wondering if the question implied globally duplicated or duplicated within subgroups. Patrick Burns patrick at burns-stat.com +44 (0)20 8525 0696 http://www.burns-stat.com (home of "The R Inferno" and "A Guide for the Unwilling S User") David Winsemius wrote:
Much simpler would be:
act2[!duplicated(act2$Rep),] #use the negation of the duplicated
function on $Rep and indexing
Date Dtime Hour Min Second Rep
51 2006-02-22 14:52:18 14 52 18 useractivity_act
52 2006-02-22 14:52:18 14 52 18 4
58 2006-02-22 14:52:52 14 52 52 3
60 2006-02-22 14:54:42 14 54 42 useractivity_idle
Cannot reproduce the blank line though.
David Winsemius, MD Heritage Laboratories West Hartford, CT
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David Winsemius, MD Heritage Laboratories West Hartford, CT