[R] Artifacts in filled.contour+pdf

[Mario Valle]

Dear all,
I'm using R 2.12.0 on Windows 7 (32bits)
I created a filled contour from the attached data using the following code:

load('bug.RData')
pdf('bug.pdf', width=14, height=7)
filled.contour(o4$x, o4$y, o4$z, color=rainbow, xlim=c(4,18), 
ylim=c(0,35), zlim=c(14,36))
dev.off()

If you look (I used acrobat reader 9.4) at the attached bug.pdf, you see 
an incomplete grid of gray lines.
This artifact is not present if the output is PNG (attached, obtained in 
the above code using png('bug.png', width=800, height=400) instead of 
pdf()).
Seems like a off-by-one bug. Is it a known bug? Is there any workaround? 
I tried lattice::contourplot but it does not support NA.
Thanks for your help!
                                                 mario

-- 
Ing. Mario Valle
Data Analysis and Visualization Group            | http://www.cscs.ch/~mvalle
Swiss National Supercomputing Centre (CSCS)      | Tel:  +41 (91) 610.82.60
v. Cantonale Galleria 2, 6928 Manno, Switzerland | Fax:  +41 (91) 610.82.82


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