width and length arguments to postscript()

Hi everyone

This must be a FAQ but I can't find it anywhere...

I want a postscript image of a contour() plot, with axes of equal
length. Try

R> postscript(file="~/f.ps")
R> contour(matrix(rnorm(100),10,10))
R> dev.off()

This isn't what I want: the plotting region is, as documented, quarter
of an inch shy of the paper edge and the axes appear to be different
lengths.  contour() doesn't take a "asp" argument.

postscript() does have a width and a length argument but I can't make
them work as I want:

R> postscript(file="~/f.ps",width=5,height=5)
R> contour(matrix(rnorm(100),10,10))
R> dev.off()

gives axes of about 96mm by 80mm (on A4 paper).

What do I have to do to get square contour plots on a postscript file?

Robin K. S. Hankin, Lecturer,
School of Geography and Environmental Science
Tamaki Campus
Private Bag 92019 Auckland
New Zealand

r.hankin at auckland.ac.nz
tel 0064-9-373-7599 x6820; FAX 0064-9-373-7042

as of: Fri Dec 13 11:07:00 NZDT 2002
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