Thanks a lot. It works but then, do you how I can have access to the result ! For instance : >g$V1 [1]Error: 'getCharCE' must be called on a CHARSXP
Regards, Steve Lianoglou a écrit : > Hi, > > On Tue, May 10, 2011 at 7:56 AM, Nicolas Servant > <[email protected]> wrote: > >> Dear Datatable users, >> >> I'm interested in using the data.table package to reduce and group high >> dimensional data (from next generation sequencing) >> I have my data.table which show me for each reads (features), the >> associated annotation. >> And because one feature can have several annotations, I would like to >> group these annotations per feature >> The numerical operations on the annotation work well (for instance >> length()), but the functions on string values seem to not work (for >> instance paste()) >> At the end, I would like to have something like : >> >> reads annot >> [1,] 1279_1000_530_F3-ad Simple_repeat, LINE >> [2,] 1279_1000_940_F3-ad snRNA >> ... >> Do you have any suggestion to do that ? >> >> >>> dt[1:20,] >>> >> reads annot >> [1,] 1279_1000_530_F3-ad Simple_repeat >> [2,] 1279_1000_530_F3-ad LINE >> [3,] 1279_1000_940_F3-ad snRNA >> [4,] 1279_1000_940_F3-ad snRNA >> [5,] 1279_1018_1051_F3-ad Simple_repeat >> > > A similar question using paste came up a few days ago ... this should > do the trick: > > R> key(dt) <- 'reads' > R> dt[, paste(annot, collapse=','), by=reads] > > Hope that helps, > -steve > > -- Nicolas Servant Equipe Bioinformatique Institut Curie 26, rue d'Ulm - 75248 Paris Cedex 05 - FRANCE Email: [email protected] Tel: 01 56 24 69 85 http://bioinfo.curie.fr/ _______________________________________________ datatable-help mailing list [email protected] https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help
