[R] PostScript scatter plot, losing points at RHS

[Jonathan Campbell]

On Apr 9, 2005 4:45 PM, Uwe Ligges <ligges at statistik.uni-dortmund.de> wrote:
> Jonathan Campbell wrote:
> 
> > I'm using the following sequence to plot a scatter plot to PostScript.
> > Those familiar with the Iris LDA example in MASS will recognise what
> > I'm at.
> 
> No, I don't recognise:
> 
> - Which edition of MASS?

My two sentences above were largely irrelevant and the link with MASS
(4th ed. p. 333) was quite oblique. Ignore them, as I would expect
most people would.

However, your suggestion of performing a replicatible experiment is
useful and an exact replica of my problem occurs in it. From MASS 4th
ed. page 304.

data(iris3); ir <- rbind(iris3[,,1], iris3[,,2], iris3[,,3])
ir.species <- factor(c(rep("s", 50), rep("c", 50), rep("v", 50)))
ir.pca <- princomp(log(ir), cor = T)
ir.pc <- predict(ir.pca)
plot(ir.pc[, 1:2], type = "n", xlab = "first principal component",
ylab = "second principal component")

Apparently good plot (to screen). The 150 data points and three
species appear to be there.

Now to PostScript.

postscript("irpca.eps", horizontal=FALSE, onefile=TRUE, height=6,
width=6, pointsize=8, paper="special")
plot(ir.pc[, 1:2], type = "n", xlab = "first principal component",
ylab = "second principal component")
text(ir.pc[,1:2], labels = as.character(ir.species))

Problem. Only 21 "s" points shown -- over on left hand side of the plot.

In my original problem also, the plot was limited 21 points.

TIA,

Jon C. 

-- 
Jonathan G Campbell  http://www.jgcampbell.com/ +44 (0)7974 663 262