Re: [R-sig-Geo] Equivalent of Region Group in spatial analyst

Nevil, You can use the freq function. After running the example I gave you can do sapply(lst, freq) or freq(s[[1]]) freq(s[[2]]) etc. (which is equivalent to table(values(s[[1]])) etc.) Robert On Tue, Sep 6, 2011 at 7:20 PM, Nevil Amos wrote: > Thanks > the second thing the Region Grou

Re: [R-sig-Geo] Cross nearest neighbor distance

On 06/09/11 01:13, Alper ALTINOK wrote: I appreciate for the advices, let me explain the situation a bit more with another example; Say, points are representing sampled fields for pests. Imagine you are making samplings from tomato fields to reveal possible clusters (hotspots) of pests, in a

Re: [R-sig-Geo] Equivalent of Region Group in spatial analyst

Thanks the second thing the Region Group does is to count the number of cells in each contiguous area can I also acheive this in Raster? On 7/09/2011 10:48 AM, Robert J. Hijmans wrote: > Nevil, > The function 'clump' in 'raster' does this for a single value and > perhaps you can use it in a lo

Re: [R-sig-Geo] Equivalent of Region Group in spatial anayst

Nevil, The function 'clump' in 'raster' does this for a single value and perhaps you can use it in a loop over all values to achieve what you are after. Robert library(raster) r <- raster(ncol=10, nrow=10) r[] <- round(runif(100)*3) u <- unique(r) lst <- list() for (i in 1:length(u)) { x <- r==u[i

Re: [R-sig-Geo] extracting simple list of adjacent neighbours

On Tue, 6 Sep 2011, Moritz Lennert wrote: Hello, I have a very simple problem, which I know will have a simple solution, but I just can't get my head wrapped around it. I have a shapefile with regions, including an attribut containing a regional id. I would like to extract a simple neighb

Re: [R-sig-Geo] Simulating spatially autocorrelated data

Hi Roger and Terry, Thank you very much for your help and directing me towards Roger's spdep package, which of course had everything I needed. I've now worked through this code and done some additional simulations. I have one remaining question. You say "the larger the distance threshold, the les

Re: [R-sig-Geo] Read HDF files

Thanks for making that crystal clear. For the moment, I will probably stick to FWtools to make my conversions, but I hope I will have time to learn how to build gdal from source including the drivers I need. Thanks again, Arnaud 2011/9/4 Roger Bivand > On Sat, 3 Sep 2011, Arnaud Mosnier wrote:

[R-sig-Geo] LOOCV for a GLM?

I'm using a Generalized Linear Model from the[R]- GLM package to do Regression Kriging in GSTAT. I was wondering if there is a way to calculate a 'leave one out cross validation' for the GLM model only? For the Regression Kriging I do it like that: ## rk.cv <- krige.cv((SAND)~om.glm, boden.ov,

[R-sig-Geo] extracting simple list of adjacent neighbours

Hello, I have a very simple problem, which I know will have a simple solution, but I just can't get my head wrapped around it. I have a shapefile with regions, including an attribut containing a regional id. I would like to extract a simple neighbourhood file, with neighbourhood defined by

Re: [R-sig-Geo] problem for installing "rgdal" package in r

This question has been asked here before. Which distribution are you using? If you are using debian or ubuntu the admin should install libgdal1-dev for building gdal. I also recommend installing r-base-dev if it is not yet installed. It is needed for building most R packages If the administrator

Re: [R-sig-Geo] problem for installing "rgdal" package in r

Hi Yung-wei, I had simislar Problems when first isntalling rgdal on my machine. It is due to missing (Linux-)Packages, that R needs to compile its bindings with gdal. In my case ( on a Ubuntu System) the required packages where: gdal-bin, libgdal1-dev, libproj-dev, build-essential. There migh