Statistical computing language and software environment.

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0
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1answer
69 views

Creating a loop for Lines data (spatial data)

I am trying to build a lines shapefile with the contour lines from the 20 meters isobath from along the East African coast. This contour line of 20 meters has different segments and I have this ...
1
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1answer
97 views

Bounding geo points

I am kinda new to geo data processing. For my sample project I am trying to solve next problem. I have array of geo points. If we place it on plot we can visually see that there are areas where ...
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0answers
23 views

Overlay Shapefile and Raster layer in R [duplicate]

I have a raster layer with climate data from the north of Mexico, part of Canada and the US mainland. I am trying to restrict the climate data to only the zone of the US mainland. To do this I thought ...
0
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1answer
269 views

How can I take a large netcdf and convert it to interpolated values in a different set of coordinates?

I've got a large netcdf (a small portion of the data is here) with the data in an even grid associated with an Albers Equal Area Conic projection. I've got the corresponding latitudes and longitudes ...
1
vote
1answer
810 views

Interpreting Moran's I results

I have a sample of data taken from regions of a country! i want to test if there are any spatial autocorrelation on my data using Moran Indice test. the null hypothesis: is that there is no spatial ...
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0answers
15 views

Plotting two shapefiles using R? [duplicate]

I'm not familiar with using R for GIS. I was wondering if you can help me figure out how to plot different shapefiles at the same time. I'm using the "map" function to generate a map in order to get ...
3
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1answer
93 views

R - Occasional error when using alphahull package areaahull() function

I've recently started using the fantastic alphahull R package, which works beautifully most of the time but occasionally I am getting the following error when running the areaahull() function: Error ...
16
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2answers
5k views

How to efficiently read a kml file into R

Hi I'm working with huge .kml files (up to 10 Gb) and need an efficient way to read them into R. Until now I've been converting them to shapefiles via QGIS and then back into R with readShapePoly and ...
5
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1answer
309 views

Specifying Bayesian Spatially lagged dependent (SAR) variable regression in winBUGS or Stan

I have been looking for code example on how to specify a SAR spatially lagged dependent variable regression in winBUGS (geoBUGS) or, if possible, in Stan. I mean, something of the format: Y = beta_0 ...
3
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1answer
139 views

How to batch generate thumbnails of raster layers with R?

I have been using R to maintain a rather large stack of raster layers (over 700 layers of data for sub-Saharan Africa). Each layer looks as follows ...
12
votes
5answers
6k views

How best to fix a non-noded intersection problem in PostGIS?

I'm using a PL/R function and PostGIS to generate voronoi polygons around a set of points. The function that I am using is defined here. When I use this function on a particular dataset I get the ...
0
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1answer
259 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 ...
0
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1answer
194 views

Want to get an SHP file for my coutry Algeria

H everyone , i'm running a clustering test on my country with R, but the problem the clustering doen't look good because of the map i have, i hant to get a bigger map of my country 'ALGERIA' in an SHP ...
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0answers
39 views

R equivalent of GRASS r.grow?

What is a good R equivalent of the GRASS function r.grow? The closest I've been able to find is the script suggested by whuber in response to Creating randomly shaped clumps of cells in a raster from ...
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0answers
34 views

Applying Spatial Clustering test using R? [duplicate]

I’m very new to R so please bear with me: I have a set of area infested by a disease (AIS) annually data and I want to apply some cluster methodology to detect regions with similar (AIS) patterns. I ...
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0answers
57 views

Performing Mutiple Correspondence Analysis (MCA) using R?

I want to apply MCA (multiple correspondence analysis) to a data table containing regions as individuals, and INFESTED AREA as variable and degree infested also and the type of trees infested , and I ...
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2answers
8k views

Return column number of min value in dataframe [closed]

So as a result of a bunch of preceding calculations I end up with a dataframe of varying numbers of rows and columns. I want to find the minimum value of the df and return the row and column index. ...
43
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10answers
6k views

What is the most useful spatial R trick?

R is becoming pretty strong tool for handling and analyzing spatial data. I learned some useful things through questions like these at SO and thought it might be useful to have something simmilar, but ...
3
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0answers
142 views

python equivalent of spatstat's spatial point process functions

Is there a free python package (i.e. PySAL?) that implements the standard summary statistics for spatial point processes, e.g. the F, G, J, and K functions? I'm happy to use R (i.e. spatstat) if ...
1
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1answer
125 views

How to compare multiple spatial point patterns over a polygon

I have multiple point pattern distributions over the same region/polygon. Each point pattern distribution has different number of points. Here is an example of two spatial point patterns for the ...
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0answers
50 views

Finding the best way to prepare raster image for a function in R

I'd like to ask what is the best way to prepare big raster images in R to run a function on whole images. I have 30 tiff images with the size of ncol=12648, nrow=4144. I read them in R separately. ...
2
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1answer
397 views

Running Random Forest Classification on WorldViev-2 image in R - problem

I have a problem with performing RF in R for a WorldView-2 Scene. I've never ever before used R for remote sensing classification, so I simply followed what is written here. I've loaded scene (8-band ...
3
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1answer
139 views

changing attributes or names of shapefiles

I am trying to join a subset of two similar shapefiles, one with states from the US and the second with provinces from Canada. The datasets are available here: shapefiles from Geocommons I noticed ...
2
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0answers
130 views

R - how to create a pre-determined number of identical square polygons to use for a choropleth map?

I am trying to plot crime data density (again!) over a city map, say of NY. As a well known problem there are plenty of examples on this ...
1
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1answer
285 views

Apply r.neighbours or Neighbourhood analysis (LecoS plugin for QGIS) to 3000 rasters

I need to apply r.neighbours or Neighbourhood analysis (QGIS plugin LecoS (or equivalent) to 3000 rasters and define a neighbourhood of 5 x 5 and calculate the mean. I suppose I need to create a ...
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2answers
92 views

Transform coordinates from NOAA

I use data from NOAA for some analysis in R and I want to transform coordinates to EPSG:54004 or something useful. There is something what they write about their coordinates. ... POS: 29-34 ...
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0answers
79 views

Error with “lowess” function in R

I have a problem with lowess function to smooth NDVI as a time in R. Here is the scripts I run: #Create a time vector to act as x time<-sort(sample(97:297, nlayers(ndvi2000crop1))) ...
2
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0answers
235 views

Decision tree classification of satellite image in R

I want to classify satellite image in R using RWeka classifier, J48. I have a CSV file with the classes required, and raster data loaded in R. I am able to make the tree, however, I am not able to use ...
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0answers
389 views

Lagrange Multiplier in lm.LMtests (spdep package for R)

Are the Lagrange values comparable in lm.LMtests? If both RLMerr and RLMlag are significant, would the test with the largest Lagrange value be considered 'better' at explaining the spatial ...
0
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1answer
489 views

How can I connect my point pattern shapefile with my polygon window in R?

I would like to do some spatial statistics in R. I have a point layer called '1983' that represents the distribution of one species, and a polygon layer called 'SA-R' that represents the study area. ...
15
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3answers
3k views

Using R with ArcGIS for Desktop (without using GME)? [duplicate]

I am trying to learn R generally and making statistics for maps. I found some useful tricks for making maps with it but it is not the best you can do. My everyday GIS program is ArcGIS. How I can use ...
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0answers
68 views

How to predict a variable as a function of time for each land cover

I have 2 images; one is time series NDVI image (26 bands) from Apr to Oct. Another one is Land cover image with 6 classes coded form 1-5. I'd like to predict NDVI as a function of time using ...
2
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1answer
629 views

Convert SpatialGridDataFrame in to polygon shapefile in R

I have a SpatialGridDataFrame in R and want to plot just one of its attributes as as polygons in a GIS. There seems to be no simple way to do this. The situation is complicated by the fact that the ...
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0answers
36 views

Analyse effect of groups on raster maps

I work with a mechanistic model that uses climate data to simulate some specific output for different time steps and spatial locations. Now I want to investigate the effect of different climate data ...
2
votes
2answers
2k views

Problem with merging and dissolving a shapefile in 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 ...
3
votes
2answers
304 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?
3
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1answer
229 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: > ...
2
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0answers
277 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 ...
0
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1answer
586 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 ...
2
votes
1answer
125 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. ...
6
votes
2answers
472 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 ...
4
votes
2answers
457 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 ...
0
votes
1answer
289 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 ...
0
votes
1answer
142 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?
5
votes
2answers
3k 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 ...
4
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0answers
32 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 ...
1
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2answers
497 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 ...
3
votes
1answer
379 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 ...
1
vote
1answer
74 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 ...
2
votes
3answers
695 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 ...