[R] Problems with labels and scaling in star diagrams

Euan Reavie euan.reavie at gmail.com
Sat Apr 17 03:32:54 CEST 2010


I have the following small dataset:

> stardata
  NS    HE    EB    CW    RW PW
1  0 0.000 0.000 0.042 0.006  0
2  0 0.006 0.000 0.013 0.005  0
3  0 0.000 0.011 0.000 0.000  0

I have plotted the star diagrams as follows:

stars(stardata,
	key.labels = dimnames(stardata)[[2]],
	labels = NULL,
	key.loc = NULL,
	draw.segments=TRUE,
	col.segments="gray",
	lty="blank")

I am having three problems. I welcome solutions for any or all of
them, or recommendations for a specific package or function that would
be better suited to my needs.

1. How do I add labels (dimnames(stardata)[[2]]) to all of the
segments, the same way they are added to the segments of the key
(which I haven't included)? The hard way would be to use the text
function with six coordinates for the variables, but surely there's an
easier way?

2. It took me a while to realize that each segment is scaled based on
the maximum for that variable (column). I would like to treat each row
independently so that all segments are scaled based on the maximum for
that row. Possible?

3. I figured one way around problem 2 would be to reduce the dataset
to one row (e.g. stardata[1,]) but that gives me an error "incorrect
number of dimensions" when I try to generate the diagram. So, I seem
to be unable to plot a single star diagram; it must be two or more.

Many thanks - Euan.
Euan Reavie, University of Minnesota Duluth.



More information about the R-help mailing list