On Fri, 9 Nov 2007, Robin Hankin wrote: > Hi > > [R-2.6.0, macOSX 10.4.10]. > > The helppage says that rowSums() and colSums() > are equivalent to 'apply' with 'FUN = sum'. > > But I came across this: > > > a <- matrix(1:30,5,6) > > is.integer(apply(a,1,sum)) > [1] TRUE > > is.integer(rowSums(a)) > [1] FALSE > >
'equivalent' does not mean 'identical': the wording was deliberate. > so rowSums() returns a float. And that is what the help page says it does (albeit more accurately: there is no 'float' type, but there is numeric aka double and the result could be complex). > Why is this? You seem to be asking why R works as documented! -- 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.
