[R-sig-Geo] gstat: Cokriging with unusual neighbourhood choice - is this possible?

2013-07-23 Thread Ralph Mettier
I'm looking at two variables, concentration and precipitation, measured at two networks of stations: network A measures both variables at few (~30), widely spaced stations network B measures only precipitation at many (~1800) densely spaced stations a decent correlation between the two variables

Re: [R-sig-Geo] gstat: Cokriging with unusual neighbourhood choice - is this possible?

2013-07-23 Thread Edzer Pebesma
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Dear Ralph, I guess you'd need to define three variables, concA, precA and precB. Then, you can let precA and precB have different neighbourhood specs, but make them statistically identical by specifying the same variograms for precA and precB as

[R-sig-Geo] variogram modeling using gstat

2013-07-23 Thread Moshood Agba Bakare
Dear all, I fitted a number of theoretical variogram such as spherical, gaussian, exponential, and linear to empirical semivariogram using gstat package. Please how do I assess and identify the optimal theoretical model that best fit the empirical semivariogram. Thanks while eager to read from

[R-sig-Geo] Which are the most suitable, elegant or efficient packages for geographical maps in R? Which did you use yourself?

2013-07-23 Thread Markus Jenning
Hi everyone. I remember some very interesting and professional-looking R projects that somehow involved geographical maps. Now that I'd like to work with maps myself, let me ask you this question: Which of the packages that are currently available would you think are the most elegant and

Re: [R-sig-Geo] Which are the most suitable, elegant or efficient packages for geographical maps in R? Which did you use yourself?

2013-07-23 Thread Sarah Goslee
HI Markus, That's... rather broad. I'd suggest installing the Spatial taskview, reading about what's available as part of that collection at http://cran.r-project.org/web/views/Spatial.html and then thinking about what you are trying to accomplish. Surely a more focused answer would be more

[R-sig-Geo] matching names in the input data with those on the map

2013-07-23 Thread Michael Blows
Hi all, I see someone had earlier posted similar question to the list. But, my problem is that  the counties in the input data don't match those on the map. Codes below: library(spdep) library(maps) data-read.csv(C:/Users/mitra.devkota/Desktop/MT1.csv,header=TRUE)  names(data)

[R-sig-Geo] pca on raster layers with NA's

2013-07-23 Thread César Capinha
Dear all, I have a set of 7 overlaying rasters for which I want to perform a principal components analysis and subsequently extract the corresponding maps of the two or three principal components (i.e. the scores). I've been trying to do this for a while, but I keep getting stuck in the

Re: [R-sig-Geo] pca on raster layers with NA's

2013-07-23 Thread Tim Appelhans
Hey Edward, you may find this function useful. https://github.com/environmentalinformatics-marburg/magic/blob/master/eot/src/EotDenoise.R It is designed to 'denoise' raster data (i.e. calculate all possible PCAs and only keep the first k - an integer you specify - PCAs for reconstruction).

Re: [R-sig-Geo] Using pixel image as spatstat's intensity surface

2013-07-23 Thread Allar Haav
Dear Rolf, Thank you for insightful answer. Following your explanation I found out that the key problem was that I didn't specify the simulation in Linhom envelope. For some reason I thought that lambda would be overriding the envelope creating point process. So, your example 4 was really

Re: [R-sig-Geo] pca on raster layers with NA's

2013-07-23 Thread Robert J. Hijmans
César, I think you can do princomp(na.omit(values(s)), cor=TRUE) For large objects, also see the pca example in ?raster::predict Robert On Tue, Jul 23, 2013 at 10:42 AM, César Capinha nrevist...@yahoo.co.uk wrote: Dear all, I have a set of 7 overlaying rasters for which I want to perform a

Re: [R-sig-Geo] Using pixel image as spatstat's intensity surface

2013-07-23 Thread Rolf Turner
On 24/07/13 07:56, Allar Haav wrote: Dear Rolf, Thank you for insightful answer. Following your explanation I found out that the key problem was that I didn't specify the simulation in Linhom envelope. For some reason I thought that lambda would be overriding the envelope creating point

Re: [R-sig-Geo] Using pixel image as spatstat's intensity surface

2013-07-23 Thread Allar Haav
Ah! Thank you! Exponenting the model truly fixed the problem as, indeed, the pixel image indeed stems from a multinomial logit model. I am not really sure why though, something to do with Poisson process probability function? All the best, Allar On 23/07/2013 22:57, Rolf Turner wrote: This

[R-sig-Geo] Shapefile for spatial point referenced data

2013-07-23 Thread Moshood Agba Bakare
Dear All, Please what is the usefulness of shapefile created for spatial data having longitude and latitude as spatial component and yield measured in bu/ac as attribute component. How relevant is the shapefile in the course of carrying out spatial analysis? I am a beginner. I have just created a

[R-sig-Geo] Using pixel image as spatstat's intensity surface

2013-07-23 Thread Adrian Baddeley
Allar Haav writes: I am currently trying to use spatstat's inhomogeneous cluster analysis methods (mostly Linhom), but ran into a problem. Namely, I have a pixel image (type im) with values ranging from 0 to 1 indicating point probabilities. When creating and plotting random points with it,