Re: [R-sig-Geo] A question about gwr.morantest pvalue

2012-02-22 Thread Apostolis
Thank you Apostolis -- View this message in context: http://r-sig-geo.2731867.n2.nabble.com/A-question-about-gwr-morantest-pvalue-tp7292670p7310428.html Sent from the R-sig-geo mailing list archive at Nabble.com. ___ R-sig-Geo mailing list R-sig-Geo@r-

[R-sig-Geo] gaussian filter in RASTER with differnt valuse in sigma

2012-02-22 Thread gianni lavaredo
Dear Researchers, with a low-pass guassian filter with a kernal mask of 3x3 pixel, I need to test several "sigma" value (i.e. 1, 2, and 4 or eventually different values) using "raster" library to understand the better smoothing for a further segmentation algorithm library(raster) r <- raster(nco

Re: [R-sig-Geo] GGWR (family = Poission): Prediction of unknown location

2012-02-22 Thread Roger Bivand
On Mon, 20 Feb 2012, Zia Ahmed wrote: Hello, I am trying to predict expected count for a geographical location (file name: data_181 - test data) from a another data set (data_65 - work_data) using GGWR poission model. Following R code I used. But No predicted counts were found in outpu

Re: [R-sig-Geo] Creating multidimentional vector map

2012-02-22 Thread Michael Sumner
Hmm, the subject "multidimensional" got me thinking of "rasterized" vector layers, but I think that was off-track. You can use gSimplify in the rgeos package to easily simplify a Spatial[Lines/Polygons]DataFrame as read in by readShapeSpatial (maptools) or readOGR (rgdal) (or coerced from some oth

Re: [R-sig-Geo] A question about gwr.morantest pvalue

2012-02-22 Thread Roger Bivand
On Thu, 16 Feb 2012, Apostolis wrote: Dear list members I am a new user of R and I would like to ask a question about the function gwr.morantest which is included in the spgwr package. According to the paper of Leung et al page 881 when EQ.EQ3.gwr > 0 the pvalue of the test is P(chisqh<= ch

Re: [R-sig-Geo] closest distance between irregularly-shaped polygons

2012-02-22 Thread Roger Bivand
On Tue, 21 Feb 2012, Kemp, Michael wrote: Hey Nick, There was a previous discussion on this topic in the R-sig-geo mailing list. Follow the discussion here... https://stat.ethz.ch/pipermail/r-sig-geo/2009-March/005216.html And see how the cshapes package does this (using JTS and Java to si

Re: [R-sig-Geo] Creating multidimentional vector map

2012-02-22 Thread Michael Sumner
This is a pretty open question, and there are certainly things you could do in R but I wonder if you'd be better looking elsewhere. Using GDAL gives you a lot of support for pre-rendered scales and tiled data sets, and the GDAL library has tools for rasterizing from vector layers. Also, mapserver

Re: [R-sig-Geo] setting up a spatial data frame

2012-02-22 Thread Luca Morandini
On 02/22/2012 09:52 AM, Alexandre Villers wrote: Hi Erin, You should provide us with more information: with no lat / lon data, it is going to be pretty difficult to turn your data frame into a Spatial Object... were the data collected on a regular grid, is it somehow linked to a Spatial object t

Re: [R-sig-Geo] setting up a spatial data frame

2012-02-22 Thread Alexandre Villers
Hi Erin, You should provide us with more information: with no lat / lon data, it is going to be pretty difficult to turn your data frame into a Spatial Object... were the data collected on a regular grid, is it somehow linked to a Spatial object that could be imported into R? From the last co

[R-sig-Geo] Creating multidimentional vector map

2012-02-22 Thread Antonio Rodriges
Hello, I have some shapefiles which I would like to render on a map with different scales with my own software. Is there a way to precreate vector layers (somewhat aggregated) for each map scale for the given shapefile in order to reduce the volume of data transfer and increase the visualization s