Federico Calboli wrote: > Hi All, > > Is there some document/manual about data manipulation within R that I > could use as a reference (obviously, aside the R manuals)? > > The reason I am asking is that I have a number of data frames/matrices > containg genetic data. The data is in a character form, as in: > > V1 V2 V3 V4 V5 > 1 AA AG AA GG AG > 2 AC AA AA GG AG > 3 AA AG AA GG AG > 4 AA AA AA GG AG > 5 AA AA AA GG AA > > I need, to chop, subset, and variously manipulate this kind of data, > sometimes keeping the data in its character format, sometimes converting > it to numeric form (i.e. substitute each data point with the equivalent > factor value). Since the data is ofthe quite big, I have to keep things > memory efficient. > > This whole game is getting excedingly time consuming and frustrating, > because I end up with random pieces of code that I save, patching a > particular problem, but difficult to be 'abstracted' for a new task, so > I get back close to square one annoyingly often. > > Cheers, > > Federico Calboli > >
There is a large data manipulation section on the Alzola Harrell document available on CRAN under contributed docs, or a slightly more up to date version at biostat.mc.vanderbilt.edu -- Frank E Harrell Jr Professor and Chair School of Medicine Department of Biostatistics Vanderbilt University ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html