Multiple groupedData plots in a postscript file using a loop
On Sat, 17 Jan 2004, Uwe Ligges wrote:
Karl Knoblick wrote:
Hallo!
I want to plot multiple grouped data in a postscript
file using a loop. As I use a loop no plot (or just
one empty plot) is generated. Here an example:
library(nlme)
data(Loblolly) # example data from nlme
postscript("PSFile.ps")
for (i in 1:1) # just as example
{
plot(Loblolly)
}
dev.off()
Note that this is a lattice plot:
class(Loblolly)
[1] "nfnGroupedData" "nfGroupedData" "groupedData" "data.frame"
Thus, the method plot.nfnGroupedData() producing a lattice plot is
called by the generic plot().
So, you don't want to start postscript(), but
trellis.device("postscript", file = "PSFile.ps")
plot(Loblolly)
dev.off()
Or inside a loop
trellis.device("postscript", file = "PSFile.ps")
for (i in 1:1)
print(plot(Loblolly))
# ^^^^^
dev.off()
Although Uwe is right that trellis.device should be used, recent versions
of lattice do make correct use of an open postscript() device.
Not that Master Knoblick *is* using recent lattice, as we know from an
earlier posting. See
https://www.stat.math.ethz.ch/pipermail/r-help/2004-January/042780.html
Once again he has omitted to let us know what versions he is using.
Brian D. Ripley, ripley at stats.ox.ac.uk 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