Oh, another possibility is ?mapply, which I should have pointed out in my previous reply. Sorry.
-- Bert On Sun, Sep 1, 2013 at 8:30 AM, Bert Gunter <bgun...@gene.com> wrote: > Rui et.al.: > > But apply will not work if the data frame has columns of different > classes/types, as appears to be the case here. Viz, from ?apply: > > "If X is not an array but an object of a class with a non-null > dim<http://127.0.0.1:12824/help/library/base/help/dim> > value (such as a data frame),apply attempts to coerce it to an array via > as.matrix if it is two-dimensional (e.g., a data frame) or via as.array." > > Simply looping by rows (via for() ) appears to be the simplest and > probably fastest solution. There are other ways via tapply() and friends, > but these are also essentially loops and are likely to incur some > additional overhead. > > All assuming I understand what the OP has requested, of course. > > Cheers, > > Bert > > > On Sun, Sep 1, 2013 at 7:31 AM, Rui Barradas <ruipbarra...@sapo.pt> wrote: > >> Hello, >> >> Maybe you need apply, not lapply. It seems you want to apply() a function >> to the first dimension of your data.frame, something like >> >> apply(dat, 1, fun) #apply by rows >> >> >> Hope this helps, >> >> Rui Barradas >> >> Em 01-09-2013 15:00, Ignacio Martinez escreveu: >> >>> I have a Data Frame that contains, between other things, the following >>> fields: userX, Time1, Time2, Time3. The number of observations is 2000. >>> >>> I have a function that has as inputs userX, Time1, Time2, Time3 and >>> return >>> a data frame with 1 observation and 19 variables. >>> >>> I want to apply that function to all the observations of the first data >>> frame to make a new data frame with 2000 observations and 19 variables. >>> >>> I thought about using lapply, but if I understand correctly, it only >>> takes >>> one variable. >>> >>> Can somebody point me in the right direction? >>> >>> Thanks! >>> >>> [[alternative HTML version deleted]] >>> >>> ______________________________**________________ >>> R-help@r-project.org mailing list >>> https://stat.ethz.ch/mailman/**listinfo/r-help<https://stat.ethz.ch/mailman/listinfo/r-help> >>> PLEASE do read the posting guide http://www.R-project.org/** >>> posting-guide.html <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<https://stat.ethz.ch/mailman/listinfo/r-help> >> PLEASE do read the posting guide http://www.R-project.org/** >> posting-guide.html <http://www.R-project.org/posting-guide.html> >> and provide commented, minimal, self-contained, reproducible code. >> > > > > -- > > Bert Gunter > Genentech Nonclinical Biostatistics > > Internal Contact Info: > Phone: 467-7374 > Website: > > http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm > > -- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm [[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.
