Usually there is some trick with diff or role or cumsum that can make something like this work, but all I can come up with is using Rcpp to brute force it. That works best if you create a package, but it can work okay without it if this is a one-off analysis.
Note that demolishing data as in your example makes most statisticians uncomfortable.. particularly in the name of removing outliers. I would recommend creating a quality check column and then perhaps subsetting into a new data frame if you felt it was necessary. --------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity. On March 2, 2015 6:12:44 AM PST, jeff6868 <geoffrey_kl...@etu.u-bourgogne.fr> wrote: >Hi Petr, > >Thanks for your reply, > >Actually it's not what I'm looking for. The aim is not simply to remove >each >value > 15. > >In my loop, I consider the first numeric value of my column as >"correct". >Then, I want to test the second value. If the absolute difference with >the >previous correct one is <15, it's a new correct one, but if it's >15, >then >it's a wrong one. >If it's a wrong one, it has to test the third one to check if it's >still >15 >from the last correct value (first one). >The value becomes correct again when the difference with the last >correct >one goes under 15 (and so, this value is the new "correct" one, and so >one >for the rest of the column). > >My loop is already doing the trick, but I just want to speed it up (or >maybe >another faster way to do the job). >Hope it's more understandable right now! > > > > > >-- >View this message in context: >http://r.789695.n4.nabble.com/How-to-speed-up-a-double-loop-tp4704054p4704061.html >Sent from the R help mailing list archive at Nabble.com. > >______________________________________________ >R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >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. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.