Dear R-users,

I am exploring disease spread in trees.  I have locations for diseased trees
in 2004 and 2005 and want to know whether the patterns are independent.  I
would like to use both the 'gcross' and 'kcross' functions (in spatstat).

I imported the data from two text files and created point objects using
as.ppp.  I then created a marked planar point pattern using ppp.  I am
fairly sure that everything worked, because when I ask for information about
the data file, I get
marked planar point pattern: 628 points
multitype, with levels = w2004  w2005
window: rectangle = [ 607200 , 634800 ] x [ 3438400 , 3460400 ]
(Note: the window values are so large because I am using UTM coordinates for
my x and y locations)

However, when I run gcross, I get the following error:
code: g.0405<-Gcross(oakwilt, i="w2004", j="w2005")
error: Error in hist.default(nnd, breaks = brks, plot = FALSE) :
        some 'x' not counted; maybe 'breaks' do not span range of 'x'

When running kcross, I get this:
k.0405<-Kcross(oakwilt, i="w2004", j="w2005")
Error in "[<-"(`*tmp*`, index, value = NULL) :
        incompatible types (1000) in subassignment type fix

I suspect that these two errors are somehow related.  Any suggestions for
what might be wrong?

Thanks!
Charlotte Reemts
Vegetation Ecologist
The Nature Conservancy--Fort Hood (TX) Project

	[[alternative HTML version deleted]]


