Statistical computing language and software environment.

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1answer
11 views

error of randomforest classification with Landsat data

I want perform randomforest classification on Landsat data. Here is some code I found from a paper. But when I run into the "classification" part, there is an error said "Error in eval(expr, ...
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0answers
14 views

Matching (joining) two slightly incompatible polygon shapefiles

I have two shapefiles that represent two slightly different zonings of the same area (municipality zoning and transport zones), about 3000 polygons each. Several smaller municipalities may form a ...
0
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0answers
31 views

encoding error between maptools and arcgis

I am having a trouble of encoding at writing shape file by maptools (0.8-34) of R by MacOSX and reading that by ArcMAP 10.2.1 in windows 8.1 through parallels desktop. Using an original shape file, I ...
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2answers
24 views

Include non-raster object in overlay function in R

I have two raster objects and I would like to calculate values of the first conditional on values in the second. I am currently using the overlay function, but unfortunately I can't seem to pass non ...
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0answers
17 views

R raster package split image into multiples [on hold]

I have an image as below. It is 2579*2388 pixels. Lets assume that it's bottom left corner is at 0,0. From that image I want to create multiple images as follows and save them in the working folder. ...
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29 views

Should i add coords with proj4string when using readOGR in the script if the shp doesn't contain them?

I think that by using readOGR to import a shapefile renders worthless to put proj4string to the script since if any coords are available in the shapefile will be transported through the ...
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0answers
41 views

How to set raster projection in R

I am new to R and grib files. library(raster) I have a "grd" file in and I am trying to set the coordinates to polar stereographic projection r <- raster("p190001.grd") # class : ...
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0answers
37 views

What is the most user friendly OSM route planning API?

I ran a workshop last week on GIS for Transport Applications. In Nick Bearman's tutorial (available from the previous link) we used Google's routing API (via ggmap) and CycleStreets.net routing ...
6
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1answer
214 views

How to build Poisson autoregression model

I have a SpatialPolygonsDataFrame object in R with about 3000 polygons and associated data. I have columns of expected and observed cases. For the moment, I don't have any covariates. I'd like to ...
0
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2answers
34 views

PostGIS raster write support in R

I want to push/write some generated raster layers to my postgres database directly in R. In theory this could be supported by the rgdal package, but sadly it isn't. In the latest version only copy, ...
2
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0answers
33 views

How to create geometric shapes in R? [on hold]

I want to plot some geometrical shapes but I dont know what values to put in a vector so they can be plotted. How do you know what numbers should be inserted in a vector so they can create certain ...
3
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1answer
130 views

Unsupervised classification with kmeans in R

I have a time series of satellite images (5 bands) and want to classify them by kmeans in R. My script is working fine (loop through my images, convert the images to data.frame, cluster them, and ...
1
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1answer
151 views

How to do supervised image classification in saga with the help of R script or Python script

I am using Ubuntu 12.04 and want to do image classification in SAGA. SAGA has numerous classification algorithms which is not present in GRASS and QGIS. I am new to SAGA, but more accustomed to work ...
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2answers
732 views

Calculate area covered by a particular raster layer within polygons in QGIS

I am trying to extract information on vegetation cover within a set radius of point locations (my sites). I have succeeded in creating a new vector layer of circles with a 5 km radius around my sites. ...
7
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2answers
558 views

How do I call external files in Python Geoprocessing Service?

I have created a Python script which calls an R script and then reads the output back into Python. I can run this tool in ArcGIS Desktop (10.2.1) and it works fine. When I publish as a geoprocessing ...
0
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1answer
33 views

Rasterize gives weird image

ro<-readShapeSpatial("roads") ra<-readShapeSpatial("railways") co<-readShapeSpatial("LIE_adm0") u<-union(union(extent(ro),extent(ra)),extent(co)) rast<-raster(u,res=1) ...
2
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0answers
100 views

Write raster with its attribute table and symbology

I am classifying lots of rasters and I'd like to automate the legend creation and symbology displaying for easy manipulation. Here is the kind of raster I'm dealing with: library(raster) r <- ...
1
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1answer
24 views

Shapefile One-to-Many Relationship in R

Is there any way to append a shapefile in a one-to-many relationship with its attributes that R can read? I understand the fix that resides in ArcInfo by creating through MakeQueryTable, but as this ...
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0answers
42 views

Put output of SAGA algorithm of Processing model in R script

I'm trying to combine the Variogram Cloud model of SAGA with an R script inside a Processing model. First, the R script is: ##Vector processing=group ##showplots ##Layer=table ##X=Field Layer ...
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0answers
30 views

R: how to get time-zones from latitude and longitude in raster?

I have a raster with longitudes and latitudes for the US with meteorological data (for about 100k grid points). I would like to get the time zone for each point in order to transform the time to local ...
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0answers
46 views

How to avoid “Unable to compute a transformation between pixel/line”?

I am trying to re-project from Equi-rectangular to the NASA global EASE grid (Equal Area Scalable Earth) grid 1383 586 with a ~25 km cylindrical projection (ESPG=3410). The file is provided as HDF5. ...
3
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2answers
48 views

How to compute layer by layer after stack?

I have some rasters that I want to compute the moving average and then rewrite the rasters again. r1 <- r2 <- r3 <- r4 <- r5 <- r6 <- raster(nrows=10, ncols=10); r1 <- ...
0
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1answer
202 views

Spplot labels in R how to change

Can anyone tell me how to change the labels in a legend created by spplot in R? It is a typical vertical ribbon legend automatically generated by spplot. Based on color, it is labelled 1-7 but I ...
0
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2answers
208 views

projection conversion from mercator to google maps format

Is this spTransform(Finland3, CRS("+proj=longlat +ellps=WGS84 +no_defs+ellps=WGS84 +towgs84=0,0,0 ")) the right way to project a shapefile with this projection coord. ref. : +proj=merc +lon_0=0 ...
0
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1answer
53 views

Using R to combine long/lat data into UK region polygons

I've a CSV file with geoinfo: JobSeekerId LocationId UpdatedDt EndDt Latitude Longitude Country Name JobTitle CompanyName ...
20
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2answers
7k views

How can I convert data in the form of lat, lon, value into a raster file using R?

I have a data set of values over a km grid in the continental U.S. The columns are "latitude", "longitude", and "observation", e.g.: "lat" "lon" "yield" 25.567 -120.347 3.6 25.832 ...
2
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0answers
29 views

How to re-grid a raster using area-overlap weighted averaging?

I have two rasters r and r2 with different resolutions. I want to re-sample (re-grid) r2 to be the same as r using area-overlap weighted averaging:If an r grid cell is covered by more than 1 ...
0
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0answers
23 views

How to add a plot with a different x axis to an existing plot?

I am plotting a raster but I want combine to things in the same plot but in two different axis. library (raster) r <- raster(nrows=10, ncols=10);r <- setValues(r, 1:ncell(r)) extent(r) = ...
1
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1answer
41 views

How to compute the number of none NA-values for each row?

I have a matrix(raster) that I am computing the the mean of each row in this raster as: library (raster) r <- raster(nrows=10, ncols=10);r <- setValues(r, 1:ncell(r)) # The x-values will ...
0
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1answer
126 views

Package getcartr Installation Problems

I want to build a cartogram by following this tutorial. The first thing I did, I spent the R-R-3.1.1 version 3.1.2 then I did the following: library(devtools); ...
2
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1answer
45 views

How to extract values based on names of rasters?

I have a raster r that contains values for each grid cell (which vary from one cell to another). I have other 24 rasters where the names of the rasters are: the name of r1 is data-00.img, the name ...
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0answers
35 views

Transforming GIS based XY data (polygons) so that they overlap in R

So I'm attempting to come up with the average shape of these polygon features as a part of my masters research. To do this, I want to run a shape analysis of GIS-based X-Y data using the shapes ...
-1
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1answer
82 views

How to turn shapefiles into raster and aggregate them into one raster

For example i tried this but it doesn't work rast_a<-raster(extent(shp_1)) res(rast_a)=100 rsh<-rasterize(shp_1,rast_a) rast_b<-raster(extent(shp_2)) res(rast_b)=100 ...
1
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1answer
169 views

Unable to access R from QGIS 2.4

I have been unable to run R from within QGIS on my computer. I have R version 3.03 installed and QGIS 2.4 on Windows 7. R is located at C:\Program Files\R\R-3.0.3\bin\and this is the path e specified ...
0
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3answers
490 views

Unable to run R in QGIS 2.6 - rgdal unavailable for R 3.1

I'm attempting to use R within QGIS2.6 on OSX Mavericks but cannot get R to run because rgdal is not available as binary for R3.1.2 (see QGIS log output from R execution console below). I have ...
2
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3answers
2k views

Setting “R Folder” Path in QGIS Sextante

I have installed R via the R-Project website. I have QGIS installed via OSGEO4W (currently 1.9.0 Master), and have Sextante plugin installed and working with GRASS and SAGA providers. I am now trying ...
3
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3answers
112 views

R: How to get latitudes and longitudes from a RasterLayer?

I am an absolute beginner of geographic data, so please, forgive me if the question is not appropriate. I downloaded data from NCDC NARR and managed to load into R using the raster package. I would ...
1
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1answer
77 views

Cross-validation of TPS and kriging outputs from the fields package in R

I am looking for existing package or functions that will allow me to cross-validate multiple outputs of Thin plate spline (TPS) and Kriging from the fields package. Does anyone know of any available ...
2
votes
1answer
36 views

Georeferencing in R Based on the Four Corners

I have a raster image (photograph) that was taken from a helicopter. Along with that raster image, the system also tells me the positions of the four corners of the image in a different file. I have ...
0
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2answers
43 views

Count objects in polygons

I have a .txt file containing the coordinate of the two polygons in the picture below as well as coordinates for each of the lines inside the polygons. Could anyone help to count each line inside ...
0
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0answers
10 views

DEM and r2stl() distorted models?

If I import a dem file into R and then call as.matrix() on it, I can access z values. I want to create a 3D model, but I'm getting strange results. Most of my dems are spiky and if they are smooth I ...
0
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2answers
41 views

Re-sample raster to acre grid using ArcGIS Desktop or R?

I have a 1m classified landcover raster layer that consists of values 1-4 representing various land covers. I need to resample this layer to an acre grid. Each acre in the resultant grid should ...
9
votes
1answer
649 views

Kriging on GRASS+R - cannot allocate vector of size 146.5 Mb

I'm trying to do a groundwater elevation map with an Ordinary Kriging on R, but always resulting on the lack of memory cannot allocate vector of size 146.5 Mb allocation (windows xp 32bit). ...
7
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1answer
241 views

Interpolating points observed with different time duration

I am doing spatial interpolation with a group of points. Some points have complete observation of events: for a period of 24 hours we have observed N events in each point. These points have N ...
1
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1answer
104 views

Is there any issue using R scripts with sextante processing framework?

I want to use R scripts from the module Sextante treatment QGIS , but I have many difficulties to configure the module in Sextante . Following the procedure described in the official documentation of ...
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2answers
62 views

How to convert a spatialpolygon to a SaptialPolygonsDataFrame and add a column to the atrribute table

coast<-readShapeSpatial("coastline.shp") landc<-readShapeSpatial("landcover.shp) ro<-readShapeSpatial("roads.shp") bc<-gBuffer(ro,width=100) landc$ratings=1 ...
0
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1answer
36 views

plot 3D graph based on raster pixel values

I am new to raster data. I have a raster tif file with population density value in each grid cell. I am interested in plotting a 3D graph based on raster values in ArcGIS or R. The similar graph is ...
2
votes
1answer
71 views

Monthly weather averages using NCEP/NCAR Reanalysis data

I'm a political science grad student and I've recently (and probably foolishly) committed to dipping my feet into GIS. Right now I need to build a table that has monthly precipitation and temperature ...
1
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1answer
50 views

How to create a US map in R with separation between states and clear labels?

I was trying to figure out how to create a map like down below in R on the Stack Exchange but maybe that's the wrong community and the GIS side is a better spot. Currently, I'm able to add the ...
5
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3answers
1k views

Kriging with barriers in R?

I wonder if there is a way to interpolate xyz points in a raster within certain bounds using R? In ArcGIS this is called interpolation with barriers. I wonder if there is something similar in R? I ...