If you could lead me to an example with code, that would help me figure out how to do it for my function
On Wed, Apr 18, 2012 at 3:57 PM, Louis Plough <lplo...@usc.edu> wrote: > I read it, but I guess I don't quite understand which arguments to pass > panel.groups to get different lm objects based on the two groups within > Food. > > > > On Wed, Apr 18, 2012 at 3:44 PM, Bert Gunter <gunter.ber...@gene.com>wrote: > >> Please read ?panel.superpose again and pay attention to the >> panel.groups argument, where this can be specified. >> >> -- Bert >> >> On Wed, Apr 18, 2012 at 12:34 PM, Louis Plough <lplo...@usc.edu> wrote: >> > Hi, >> > I am trying to use xyplot to plot the relationship between size and day >> > (y~x) by a food factor that has two levels, low and high. I have 3 reps >> per >> > factor/day. I want the plots from each food treatment on the same >> axiss, >> > so I used this code: >> > >> > xyplot(Size ~ Day, groups = Food, data = louis.data.means,col=1, >> > pch=c(1,17), >> > panel=function(x,y,groups,...){ >> > panel.superpose(x,y,groups,...) >> > tmp.lm<-lm(y~x) >> > panel.abline(tmp.lm) >> > panel.text(2, 250, label=format(tmp.lm$coefficients[2], digits=4), >> pos=4) >> > } >> > ) >> > This produces a graph of the two treatments (open circles for the low >> food >> > vs triangles for the high food) on the same plot, but only one >> regression >> > line (and slope) which seems to splits the difference between the two >> > factors (treats them as the same data set). I would like to produce a >> > separate regression line for the data from each of the two factors (high >> > food vs low food). >> > >> > Is there a way to subset the lm by the factor "food"? >> > >> > Louis >> > >> > [[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. >> >> >> >> -- >> >> 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.