Prof Brian. thanks, I have check the on-line Errata at http://www.stats.ox.ac.uk/pub/MASS4/Errata4.2 before, for the second printing. I don't know it depends on the first printing Errata at all.
and sorry again for my anonymous posting. I am not a native English speaker, and I should learn how to observe these proprieties(at least, some basic network etiquette). I 'll try to correct this as soon as possible. Best Regards, Ma Yun(We put the Last Name before the First name, Ma means horse or pointless for it's a last name, Yun means cloudy,) China,P.R.C. Shanghai. LongDong RD 2386. On Nov 8, 2007 3:30 PM, Prof Brian Ripley <[EMAIL PROTECTED]> wrote: > A lot of those changes are of course in the on-line Errata at > http://www.stats.ox.ac.uk/pub/MASS4/Errata4.1 . E.g. > > R Changes > ========= > > p.12 As from R 1.7.0 data() is not needed for our datasets, but it > is needed for R's own datasets ability.cov, iris3 and swiss > prior to R 2.0.0. > > > > On Thu, 8 Nov 2007, [EMAIL PROTECTED] wrote: > > > The book came out in 2002 and a lot has happened with R in the time since > > then. In particular it is now possible for R to have 'lazy loading' of > > objects. If the person setting up the package has used this option (as > > they all now should), when the package is loaded R essentially is made > > aware that the data (and other) objects are there, so it is visible, but it > > is only read into memory if it is used. The little tag that alerts R to > > the existence of the object and triggers the automatic loading on demand is > > called a 'promise' and the action itself is called a 'delayed assign'. > > > > Previously this all had to be done manually. data() could be used either > > to discover what data objects were available in packages, or to load them > > in to memory. Many old-style packages still require you to do this. There > > are cases where it is justified, I suppose, but they are quite hard to > > think of... > > > > With R you have to keep abreast of developments, and it's all happening > > pretty fast. > > > > Bill Venables. > > > > PS Since you are new to R, it is not considered very friendly to send > > messages to the R groups anonymously. > > > > > > Bill Venables > > CSIRO Laboratories > > PO Box 120, Cleveland, 4163 > > AUSTRALIA > > Office Phone (email preferred): +61 7 3826 7251 > > Fax (if absolutely necessary): +61 7 3826 7304 > > Mobile: +61 4 8819 4402 > > Home Phone: +61 7 3286 7700 > > mailto:[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> > > http://www.cmis.csiro.au/bill.venables/ > > <http://www.cmis.csiro.au/bill.venables/> > > > > -----Original Message----- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] <mailto:[EMAIL > > PROTECTED]> ] On Behalf Of envisage > > Sent: Thursday, 8 November 2007 1:27 PM > > To: r-help@r-project.org > > Subject: [R] a newbie question about "data" > > > > hi, I am reading Modern Applied Statistics with S 4th ed¡£ > > page4 have these two lines: > >> library(MASS) > >> data(chem) # needed in R only > > but I find withou the line " data(chem)" > > I can still access chem, isn't it? > > is it unnecessary or something i missed here? > > thanks for the replay in advance. > > > > > > -- > 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 > ______________________________________________ > 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.
