On 08/06/2015 6:04 AM, Christian Brandstätter wrote: > Thank you for the explanation. > But if you take for instance plot.default(), being another generic > function, it would not work like that: > plot(1,2,3,4), only plot(1,2) is accepted. > > > From R-help (Usage): > ## Default S3 method: > mean(x, trim = 0, na.rm = FALSE, ...) > > What is puzzling, is that apparently na.rm (and trim, which is indicated in > the help) is accepting numeric values. > mean(c(1,NA,10),10,TRUE) > mean(c(1,NA,10),10,FALSE) > > This should give at least a warning in my opinion.
It is a common idiom in R programming to treat non-zero values as TRUE, and zero as FALSE. If every use of a number where a logical is needed generated a warning, you'd be swamped with them. Duncan Murdoch > > mean(c(1,NA,10),10,200) > > > > On 08/06/2015 09:27, Achim Zeileis wrote: > >> On Mon, 8 Jun 2015, Christian Brandst�tter wrote: >> >>> Dear list, >>> >>> I found an odd behavior of the mean function; it is allowed to do >>> something that you probably shouldn't: >>> If you calculate mean() of a sequence of numbers (without declaring >>> them as vector), mean() then just computes mean() of the first >>> element. Is there a reason why there is no warning, like in sd for >>> example? >> >> mean() - unlike sd() - is a generic function that has a '...' argument >> that is passed on to its methods. The default method which is called >> in your example also has a '...' argument (because the generic has it) >> but doesn't use it. >> >>> Example code: >>> mean(1,2,3,4) >>> sd(1,2,3,4) >>> >>> Best regards >>> Christian >>> >>> ______________________________________________ >>> [email protected] mailing list -- To UNSUBSCRIBE and more, see >>> 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. >>> > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > [email protected] mailing list -- To UNSUBSCRIBE and more, see > 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. > ______________________________________________ [email protected] mailing list -- To UNSUBSCRIBE and more, see 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.
