Statistical computing language and software environment.

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How to analyse point data as covariate for areal data

I have two data sets. a) a set of polygons with areal data variables. b) point measures of various co-variates of interest (note I do not necessarily have a point for each polygon) How do I correctly ...
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11 views

Error in unionSpatialPolygons using R

I am migrating from ArcMAP to opensource GIS. I've succesfully installed R and many packages in a Ubuntu 12.04 machine. I am used to linux and programming in C, but not to R and its syntax. I am ...
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11 views

error in using akima package in r for irregular point data interpolation

I am tring to interpolate my irregular Point data with an Elevation value. I found akima package for Interpolation and tring to use it but it Shows error message like this: Error: could not find ...
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1answer
34 views

Conducting geographically weighted regression on a raster

I have a relatively big raster file on which I want to conduct geographically weighted regression. Size of raster ~ 2 GB and number of rows is around 100,000 One way might be to convert from raster ...
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5 views

Unserialize socklist error when using rasterEngine in r

Basically, I am running the "rasterEngine" function in R. I want to use parallelization to change values in a raster image (I have around 400 images that I need to work on). However, the rasterEngine ...
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17 views

RasterStack extract() for duplicated dates

I have a a Large RasterStack of temperatures and a 10570 points in a Large SpatialPointsDataFrame and I'm using extract() to assign the temperatures to each point in R. ...
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6 views

Creating a loop to predict over small areas

Based on a SDM, I am I am trying to use the predict function (raster package) to predict the model to South Africa. It runs off memory and gives me an error when I predict for the entirely country, ...
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1answer
25 views

writeOGR column limit error: “Creating Name field failed”

I have a SpatialPointsDataFrame with 1057 elements and 4760 columns and want to export it to a shapefile. When I try to do this with writeOGR() I get an error: > ...
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11 views

How to get specific coordinate system to get arcGIS point shapefile in r?

I have a Point shapefile from arcGIS 10. I want to get it in r and also want to get it a specific predefined coordinate systen for my data. I can read the shapefile in R but summary in r Shows ...
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22 views

Connecting Grass with R

I need help to connect R with Grass. In RStudio when I send the line: loc <- initGRASS("C:/Program Files/R/R-3.1.0/bin/i386", home=tempdir(), override=TRUE) It says: Error in ...
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16 views

How do I peform a true GIS Clip of polygons layer using a polygon layer in R

I'd like to do a true GIS Clip in R of soils polygons using a series of single boundary polygons, but I cannot find an R function to properly do it. It should work just like the CLIP function in ...
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21 views

How to open a raw binary raster in QGIS or R

I have a raw binary raster without a file ending, and no header file. I would like to open this in either QGIS or R and then convert to geotiff, but opening it seems to be a challenge. Here is a ...
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45 views

Select polygons that do not intersect any other polygon using QGIS, GRASS, SAGA or R

I would like to select the polygons of the layer below that do not intersect with any other polygon (within the same layer). How can I do this using QGIS, GRASS, SAGA or R?
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1answer
34 views

Saving kriging information from automap package in the ESRI ASCII raster format

I would like to save the information generated from an ordinary kriging (processed with the function autoKrige from the automap R package), into a file extension readable in ArcGis for desktop 9.3.1 ...
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1answer
28 views

Averaging XY points locations if in close proximity automatically over a large dataset in R

I have a point dataset (XYZ values) containing a few million points covering a 5km x 5km extent representing maxima locations. However there a great deal of these points which exist in 0.5m of others. ...
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23 views

calculate distance between points crossing the antimeridian

How can I calculate the distance between two points (lon/lat) if any of the points exceeds the antimeridian (+-180 longitude)? Im using the distVincentyEllipsoid {geosphere} to calculate the shortest ...
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11 views

display followers count on google maps using R

How can I plot the count of followers, locations wise on google maps- Im using R language my data is as below for(i in 1:25){print(friends_obj[[i]]$location)} [1] "London & Glasgow/Edinburgh, UK" ...
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1answer
28 views

Point-sampling rasters using R? [duplicate]

I need to be able to sample many raster files (imported from GeoTIFFs) using a previously defined set of spatial points, using R. What's the best way to do this?
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29 views

How do I generate a correlogram from a GeoTiff using R?

I'm trying to evaluate the scale of spatial autocorrelation for a bunch of rasters I have as GeoTIFFs. I'd like to be able to do this entirely using R, in order to maintain smooth workflow. What's ...
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2answers
81 views

Extract Raster from Raster using Polygon shapefile in R

I am new to R and using the raster package. I have a problem extracting polygons from an existing raster file. If I use extract(raster, poly_shape) function on the raster it always creates a list ...
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24 views

Projecting polygon when calculating its area? [duplicate]

I have a broad range of polygons (in vector format and in SpatialPolygonsDataFrame class), some going east-west, others going south-north, while even others span polar regions or very large ranges as ...
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41 views

Compute the area of a given polygon (in vector format) lying between specified lines of latitude

I have species distributions (in vector format) and I would like to calculate how much of the area for a given species distribution is within certain lines of latitude, such as temperate and tropic ...
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32 views

Plotting spatial data when two spatial objects have different CRS

I have a spatial polygon object and a spatial points object. The latter was created from xy latlong data vectors (called latitude and longitude, respectively) in a dataframe, while the former was ...
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1answer
44 views

How to deal with empty corners in raster when calculating fragmentation index

I have clipped buffer area around coordinate from one big raster (forest cover). Such created raster was loaded in R where PatchStat function (library SDMTools) gives fragmentation index. After ...
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3answers
55 views

R - color SpatialLines by attribute

I have a SpatialLinesDataFrame dataset of rivers in R. The dataset consists of lines (river segments) with a "Turbidity" attribute. I want to create a map and legend, where: Turbidity between 0 and ...
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87 views

Converting shapefile to raster: Character attributes

I've got a shapefile that I would like to convert into a raster, but the trick is that the attribute I want a raster version of is character data. I'm familiar with geoprocessing using GDAL (in the ...
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13 views

formula for GWPCA cross validation on GWmodel package on R software

i want to know the formula of for GWPCA cross validation to get the best bandwuth on GWmodel package on R software. thanks
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2answers
55 views

How to create a time series with a NetCDF raster from Ensembles E-OBS using GDAL, R, GRASS GIS or SAGA GIS

I downloaded a NetCDF file that contains daily precipitation values from 1-1-1950 to 30-6-2013. The raster has 23191 bands. http://eca.knmi.nl/download/ensembles/download.php My goal is to analyze ...
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26 views

Failure to display R script result plots in QGIS

I'm trying to run R scripts (3.0.2) from QGIS (2.0.1) on Windows 7 x64. There seems to be a known bug whereby the output results do not display in the QGIS GUI, but rather just an html path ending in ...
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46 views

R raster Package Moran's I interpretation

I am using raster package to calculate the local Moran's I . The example gives the range of Moran's I between - 1 to 2.47. On my own data I have see the value range -3.070423 - 7.228558 How can ...
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92 views

How can I conduct Geographically Weighted Analysis using an exponential decay function?

I have some points (representing 30 study sites) and I want to calculate the weighted mean of several variables (landscape layers) using a negative exponential decay (weights function) to give more ...
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2answers
63 views

join grid or polygon layers in R

I have two grids. Cells in each grid have an attribute. Size of grid cells differs between the two grids and the two grids do not overlay each other perfectly. I would like to create a new layer, ...
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1answer
34 views

Plot a Raster in R with white space for NA values

I want to produce a .png of a raster with background values plotted as white space. Below you can see the current state of the plot. As you can tell, the pixels which should contain NA values, ...
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3answers
148 views

Convert 800 .hdf4 files to Tiff using GRASS/QGIS/SAGA/GDAL/R

I've have MODIS ndvi data (MODIS_Grid_16 days NDVI) from the iberian peninsula, from February of 2000 to August of 2012 (really big data). How do I batch convert about 800 .hdf MODIS files to .tif ? ...
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2answers
40 views

R - What is the purpose of .GAL lattice file?

Could someone please explain to me what the purpose of a .GAL lattice file is? I want to see if my data are spatially autocorrelated and I've been following Bivand (2013). I have loaded my polygon ...
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62 views

R Raster package loop over pixels

I want to perform a trend analysis for each pixel over it's time dimension. Therefore I wrote a loop over each pixel doing the calculation but this is extremely slow. I am sure there must be a faster ...
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33 views

Resources for mapping and displaying spatial data in R

I'd like this to be a repository for all resources available specifically for mapping and displaying spatial data in R. I've seen (and contributed) to this post, but would like this post to focus ...
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1answer
163 views

How to process MODIS ndvi data using QGIS/GRASS/R?

I have MODIS ndvi data (MODIS_Grid_16 days NDVI) from the iberian peninsula (3 tiles), from February of 2000 to August of 2012 (really big data). I want to know how to deal with this kind of files. My ...
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179 views

Calculating spatial lags per year in R

At the moment I am having some difficulties with calculating a spatial lag in R. I know how to calculate the lag in space-wide format but am unable to do it in long form, i.e. have repeated ...
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68 views

Defining the boundary of a catchment area

I digitized contour lines from topographic maps and created a DEM. With the DEM, I estimated the boundary of a catchment area. Estimated positional accuracy of topographic maps is RMSE = 65 m, with a ...
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1answer
33 views

Matching two point clouds without loss (nearest neighbor, but more complicated)

I have two point clouds, one with demographic and one with electoral data. Points in both clouds represent the same empirical entity (say, a village, or an urban neighbourhood), but are not in the ...
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1answer
71 views

R - Dealing with missing data in SpatialPolygonDataFrames for Moran.test

I'm trying to use Moran.test on a SpatialPolygonDataFrame consisting of 7194 elements in R. I know that there is around 150 polygons with NA values. First I generate a spatial weights matrix: ...
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89 views

Per-pixel calculations on a raster stack using GDAL

In R, it's relatively trivial to perform per pixel calculations based on a raster stack (e.g., get std.dev for each pixel on a 12 layer GeoTIFF). Unfortunately, the speed is less than desirable when ...
2
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1answer
60 views

Conversion of Latitude/Longitude to different map projection

I have two m*n matrices coming from a WRF-ARW simulation: one exclusively with longitude values and one with only latitude values. For both matrices I know the originatin projection (lambert conic ...
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220 views

Overlay a spatial polygon with a grid and check in which grid element specific coordinates are located

How can one use R to split a shape file in 200 meter squares/sub-polygons, plot this grid (incl. ID numbers for each square) over the original map below, and evaluate in which square specific ...
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103 views

How to create a loop in R to average ndvi raster time series?

I have monthly ndvi raster geotiffs for multiple years. I need to run a loop to get the average of each of these ndvi grids/rasters. Each of my ndvi rasters contains 143 pixels. I would like the ...
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41 views

How to infer a relationship between two spatial points using R

I am quite new to the area of spatial statistics, but I'm very interested. For learning and demo purposes, I've created three datsets. Dataset - Persons: This describes individuals at a certain ...
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58 views

Performing cluster analysis in R with Point Datasets

I am a R-Beginner, but I want to use it for some spatial statistics. I want to check the relation between the occurrence of ill persons and the existence of water in a area of interest. To give you a ...
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79 views

Calling 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 ...
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2answers
91 views

SpatialPointsDataFrame properties and operators in R

I have created an object of type SpatialPointsDataFrame using the sp package in R. However, I am confused about the @, $, . and [] operators and when to use them to access the different properties of ...