thanks you all for the replies, it's been very helpful.
regards Prof Brian Ripley wrote: > > On Mon, 23 Jun 2003, Murad Nayal wrote: > > > - what is the correct way to -remove- a component from a list. this > > seems to do the trick: list[[1]] = NULL, however, you'd think this > > should simply attach a NULL object at the first component position? > > This is in the FAQ, section 3.3.3, and is an S/R difference that catches > people quite often. It's related to the difference between [] and [[]]. > > Generally you will find that it is better to program by generating whole > lists with lapply() or to copy lists retaining what you want (which does > not copy the components, in general, and so is cheap). > > As for your comments on books: `S Programming' does discuss the design of > classes (both informal and formal), the main data sructures in R. As > others have said, the Green Book (Chambers, 1998) is by not means out of > date, except in the sense that the precise langage it describes has never > been available: it is not a description of any version of S-PLUS nor R. > > Generally, though, you need to make sure you have at your fingertips the > resources which come with R: the various manuals (including R-lang) and > the on-line help. For example, I have just spend several days documenting > in the help pages exactly how subscripting of data frames works (and > correcting dozens of anomalies and bugs). > > -- > Brian D. Ripley, [EMAIL PROTECTED] > Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ > University of Oxford, Tel: +44 1865 272861 (self) > 1 South Parks Road, +44 1865 272866 (PA) > Oxford OX1 3TG, UK Fax: +44 1865 272595 > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help -- Murad Nayal M.D. Ph.D. Department of Biochemistry and Molecular Biophysics College of Physicians and Surgeons of Columbia University 630 West 168th Street. New York, NY 10032 Tel: 212-305-6884 Fax: 212-305-6926 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
