On Mon, 8 Dec 2003, Pascal A. Niklaus wrote: > Martin Maechler wrote: > > >>>>>>"Pascal" == Pascal A Niklaus <[EMAIL PROTECTED]> > >>>>>> on Mon, 08 Dec 2003 11:47:02 +0100 writes: > >>>>>> > >>>>>> > > > > Pascal> Hi all, is there an easy way to build up a data > > Pascal> frame by sequentially adding individual rows? > > > >yes, pretty easy, but usually not recommended because quite > >inefficient. > > > >rbind() does work with data frames in the cases we know. > >Have a look at help(rbind.data.frame) > > > > > > Pascal> The data frame consists of numeric and character > > Pascal> columns. I thought of rbind, but I ended up with > > Pascal> numeric values for the character columns. > > > >We'd need to see [i.e give a reproducible example!] > >how you "ended up with numeric values for the character > >columns" -- which I guess were *factor* instead of character ? > > > > > Yes, there was a factor... There's one problem left, though... The row > names are 1, 11, 111 etc, instead of 1,2,3... > > > df <- NULL; > > > > df <- rbind(df,data.frame(A=1,B="abc",C=rnorm(1))) > > df <- rbind(df,data.frame(A=1,B="abc",C=rnorm(1))) > > df <- rbind(df,data.frame(A=1,B="abc",C=rnorm(1))) > > df > A B C > 1 1 abc 1.3540030 > 11 1 abc -0.7229597 > 111 1 abc -0.4922653 > > Of course, I can do a attr(df,"row.names") <- 1:3 at the end, but is > there an easier way? Ideally, I would like to name the row already when > adding it to the data frame.
Easy! Create the data frame with the row names you want -- see ?data.frame. > Is there another way than setting the > row.names attribute "manually" with the attr command? What do you think row.names<- does? -- 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 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
