Re: [R-sig-Geo] values of Moran´s I index

2011-04-06 Thread Roger Bivand
On Wed, 6 Apr 2011, Robert Pazur wrote: Dear all, with usage of spdep package I tried to explore the impact of changing location of occurrence of 1?s in binary fashion on Moran index by shifting an artificial 9pixel- square (small square left below in the picture) in all direction (based on

Re: [R-sig-Geo] Colouring maps so that adjacent polygons differ in colour

2011-04-06 Thread Karl Ove Hufthammer
Barry Rowlingson wrote: topocolours (I wrote that!) uses the same greedy algorithm once its worked out the connectivity. I did make topocolours have the flexibility to choose other algorithms but only implemented the greedy one. The problem with real world maps is that some features have more

Re: [R-sig-Geo] Colouring maps so that adjacent polygons differ in colour

2011-04-06 Thread Roger Bivand
On Wed, 6 Apr 2011, Karl Ove Hufthammer wrote: Barry Rowlingson wrote: topocolours (I wrote that!) uses the same greedy algorithm once its worked out the connectivity. I did make topocolours have the flexibility to choose other algorithms but only implemented the greedy one. The problem with

Re: [R-sig-Geo] Residual variogram from known trend

2011-04-06 Thread Paul Hiemstra
Hi, You could try to (ab)use the standard lm function. First calculate the regression using lm, than replace the fitted coefficients by the values you want them to have and than use predict to estimate the values at your measurement locations. Subtracting that value from the measurements gives

Re: [R-sig-Geo] Colouring maps so that adjacent polygons differ in colour

2011-04-06 Thread Barry Rowlingson
On Wed, Apr 6, 2011 at 8:38 AM, Roger Bivand roger.biv...@nhh.no wrote: I've asked Barry off-list about this, there was a case a little while ago with unexpected results because of inserted sliver polygons causing apparently separate observations to be neighbours (the slivers were only

Re: [R-sig-Geo] Colouring maps so that adjacent polygons differ in colour

2011-04-06 Thread Karl Ove Hufthammer
Barry Rowlingson wrote: I've asked Barry off-list about this, there was a case a little while ago with unexpected results because of inserted sliver polygons causing apparently separate observations to be neighbours (the slivers were only visible when zooming right in). There are also

Re: [R-sig-Geo] Cokriging unbiasedness condition

2011-04-06 Thread Piero Campalani
Thank you. So that means that e.g. with ordinary cokriging, the one condition sum of all coefficients equal 1 is used, and not e.g. the (n+1) nonbias conditions by which the coefficients of the target variable sum to 1, whereas the coefficients of the n secondary variables sum to 0 ? I'm sorry,

[R-sig-Geo] plot raster map

2011-04-06 Thread Fabrizio Diotri
Hi to everybody, I'm new to this list. I load a raster map in R thanks to spgrass6 package: no problem. I would like to plot it: with image command no problem. The problem is that I would like to mantain original map colours. My map is catgorized and in particular: category red green blue

Re: [R-sig-Geo] Cokriging unbiasedness condition

2011-04-06 Thread Piero Campalani
Well, I am asking this because in An Introduction to Applied Geostatistics, §17, they point out how these that are meant as usual nonbias conditions are not believed to be the best ones, though they are the most commonly used.. Using just one nonbias condition involving all the cokriging

[R-sig-Geo] varying polygon layer with panel in spplot

2011-04-06 Thread Matthew Landis
Dear R-sig-geo followers: I wonder if anyone can help me with the following problem. I'd like to plot a series of rasters overlaid with polygons (or points), where the polygon layer is specific to each panel. here's an example of my nearest attempt using spplot on a Meuse-based dataset

[R-sig-Geo] Calculating/applying transition matrices from classified imagery?

2011-04-06 Thread Jonathan Greenberg
Folks: Does anyone know of a package (or a suggestion on how to implement) to calculate, for two classified raster images of the same location but different times, the relative probability of transitioning from one class to the other? Additionally, once this is figured out, how to apply this

Re: [R-sig-Geo] Calculating/applying transition matrices from classified imagery?

2011-04-06 Thread Roman Luštrik
At least for the first part, if you already have a model (and a function), you could calculate the probability of transition between classes using raster::calc function. s - stack(r, r*2, sqrt(r)) # return a RasterLayer rs1 - calc(s, sum) Cheers, Roman On Thu, Apr 7, 2011 at 12:07 AM,