Hi,
I don't think this is a bug, but I thought I'd mention it in case
others think it is not correct... I guess it is probably just a
rounding error.
If I use symbols() to draw some circles, any circle with radius of
zero gets drawn as a small circle. As an example:
postscript(file="test.ps")
symbols(1:9, rep(2,9),
circles=seq(from=0.05, to=0.0, length=9),
inches=FALSE, xlim=c(0, 10), ylim=c(1,3))
dev.off()
The rightmost circle should be of radius 0, but looking at the plot it is
drawn bigger than both the previous two circles.
The workaround I used was to change any radius of 0 to NA so that no
circle is then drawn.
Stephen
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On Mon, 3 Jun 2002, Stephen Eglen wrote:> Hi, > > I don't think this is a bug, but I thought I'd mention it in case > others think it is not correct... I guess it is probably just a > rounding error. > > If I use symbols() to draw some circles, any circle with radius of > zero gets drawn as a small circle. As an example: >It seems to be deliberate. In src/main/graphics.c:GCircle we have ir = radius/Rf_gpptr(dd)->ipr[0]; ir = (ir > 0) ? ir : 1; so that a circle of radius zero is set to a positive radius. What I don't know is whether this is needed -- perhaps some devices won't draw zero-radius circles correctly, for example. -thomas Thomas Lumley Asst. Professor, Biostatistics tlumley at u.washington.edu University of Washington, Seattle -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._