So you need to show us how you made the second object. (The Posting Guide's phrase "reproducible code" is hereby invoked.)
On Aug 3, 2009, at 10:18 AM, Paulo Eduardo Cardoso wrote: > Both objects are numeric, but they differ in structure and I don't > know how to handle both with a single function to get means. > > When I try to apply colMeans to a named numeric object like this: >> Named num [1:2] 670 314 >> - attr(*, "names")= chr [1:2] "x" "y" > > I get the error messages: > > Error in colMeans(centroid) : > 'x' must be an array of at least two dimensions > > and apply(object,2,mean) > > Error in apply(object, 2, mean) : dim(X) must have a positive length > > There are something very basic that I'm missing. > > 2009/8/3 David Winsemius <dwinsem...@comcast.net> > > On Aug 3, 2009, at 9:52 AM, Paulo Eduardo Cardoso wrote: > >> Thanks. Works >> >> A doubt. >> >> I asked that because I have a loop that can generate objects like >> that or this one >> >> >> str(object) >> Named num [1:2] 670 314 >> - attr(*, "names")= chr [1:2] "x" "y" >> >> To avoid using a ifelse() to calculate means of x and y, I'd like a >> function that handle with this named numeric object and that list. >> Any chance of do it with a single function? > > I do not see any list object. Lists and arrays (of which the two > dimensional ones are of type "matrix") are quite different basic > data structures in R. If you interchange the use of those terms you > will not get useful replies from R users. Those two object both > appear to be matrices and both should be handled by those functions. > > >> 2009/8/3 David Winsemius <dwinsem...@comcast.net> >> >> On Aug 3, 2009, at 9:07 AM, Paulo Eduardo Cardoso wrote: >> >> Maybe a very basic question. >> How can I get mean of a object like this >> >> str(object) >> num [1:53, 1:2] 734 734 736 734 736 ... >> - attr(*, "dimnames")=List of 2 >> ..$ : NULL >> ..$ : chr [1:2] "x" "y" >> >> I want the mean of both x and y >> >> apply(object, 2, mean) >> >> or... >> >> colMeans(object) # which will be faster >> >> David Winsemius, MD Heritage Laboratories West Hartford, CT [[alternative HTML version deleted]] ______________________________________________ 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.