Dear R helpers,
When producing a PCA biplot, vectors of environmental variables (as
red arrows with labels) and scores of the observations (black labels
(observation names)) are plotted by default. How can I change the
graphical output? Let's say I would like that the scores are plottet
only as symbols and not text. The only solution I found was this post
in the help archive
http://tolstoy.newcastle.edu.au/R/e2/help/06/12/7298.html
suggesting "cheating" like:
biplot(test.pca, xlabs=c("0","0","0","0","0","0...
and using letters instead of symbols.
This works somehow, but I am still not able the change e.g. the colour
or size of only the scores. Whatever I try to do with "col=...",
"cex=..." and so on changes either all labels in the plot or none. Can
someone tell me what is the trick to only modify either the
environmental variables or the scores? Also e.g. the type of the arrow?
Thanks in advance,
Axel
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