You might be interested in package "bit". --------------------------------------------------------------------------- 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.
"Jonas Jägermeyr" <jonas...@pik-potsdam.de> wrote: >Dear R-help members, > >I'm processing a large amount of MODIS data where quality assessment >information is stored as an integer value for each pixel. I have to >converted this number to an 8 digit binary flag to get access to the >stored quality code (e.g. in2bin(165,8) = 1 0 1 0 0 1 0 1). > >Unfortunately, I did not manage to find a package providing a fast >function to do so. I need to run this on millions of pixels and thus >wrote the following function. > >int2bin <- function(x,ndigits){ > base <- array(NA, dim=c(length(x), ndigits)) > for(q in 1:ndigits){ > base[, ndigits-q+1] <- (x %% 2) > x <- (x %/% 2) > } > bin<- apply(base,1,paste,collapse="") > return(bin) >} > >Since it is still slow, I have to find a way to express this more >elegantly. I'd really appreciate any help. > >Thanking you, with best regards > >Jonas J�germeyr > >Potsdam Institute for Climate Impact Research >Research Domain II > > [[alternative HTML version deleted]] > >______________________________________________ >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. ______________________________________________ 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.