Statistical computing language and software environment.

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2
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1answer
129 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 ...
2
votes
1answer
41 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
27 views

In R, set NA cells in one raster where another raster has values

I have two rasters in R. I want to set values to NA in the first raster where the second raster has values. I think this should be simple, using the raster package, with two RasterLayer objects ...
2
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0answers
71 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 ...
0
votes
1answer
78 views

Test for spatial randomness with Ripley's K or L function in R

I have a spatial point pattern that I would like to test against complete spatial randomness. I managed to plot a Ripley's K function for my data and a function for a random distribution with a ...
0
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0answers
35 views

How to crop an image into more than 80 small sections automatically in R

I'd like to crop an image into 15 sections in R. The image projection is Geog lat/long, extending 87 to 120 degree in East and 45 to 55 degree in North. I want to separate it by every 2 degree. So I ...
0
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2answers
51 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 ...
1
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0answers
37 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))) ...
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0answers
34 views

Sextante and qgis for hotspot analysis

I want to analyze time series data for hotspot analyis. May i know whether sextante and qgis are able to generate any spatial statistics similar to Getis-O-ord in ARCGIS.Or R is required for hotspot ...
2
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0answers
86 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 ...
1
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0answers
50 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 ...
1
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0answers
31 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 ...
3
votes
1answer
100 views

Spatial Classification

I am not sure what to call my problem. From this image, I have a set of classified polygons (colored). I would like a way to classify the white polygons in the image. I don’t have any attributes to ...
0
votes
1answer
88 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. ...
0
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0answers
38 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
votes
1answer
114 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 ...
1
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0answers
32 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 ...
1
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1answer
82 views

converting coordinates from unusual DMS format to decimal

So I've been shared a dataset with what to me is an unusual format for degree min second data. In their own words: The coordinates provided are longitude and latitude in degrees minutes and ...
1
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1answer
61 views

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 ...
2
votes
2answers
363 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 ...
0
votes
1answer
96 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
votes
0answers
112 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 ...
1
vote
1answer
22 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. ...
0
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0answers
17 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, ...
3
votes
1answer
70 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: > ...
0
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0answers
35 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 ...
0
votes
1answer
133 views

Trilateration algorithm for n amount of points in R?

I read the page Trilateration algorithm for n amount of points and I have to do similar kind of trilateration in R. I am not that expert in R, can anyone help, if there is similar function/package ...
1
vote
1answer
98 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 ...
1
vote
1answer
85 views

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

I would 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 ...
0
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0answers
65 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 ...
3
votes
2answers
109 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?
0
votes
1answer
152 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
62 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. ...
0
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0answers
50 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 ...
1
vote
0answers
51 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, ...
0
votes
1answer
43 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?
0
votes
1answer
112 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 ...
3
votes
2answers
592 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
votes
0answers
28 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 ...
2
votes
1answer
103 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 ...
2
votes
1answer
59 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 ...
1
vote
1answer
55 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
136 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 ...
4
votes
2answers
135 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
0answers
27 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
1
vote
2answers
125 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 ...
0
votes
0answers
63 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 ...
5
votes
1answer
216 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 ...
7
votes
1answer
135 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 ...
4
votes
2answers
121 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, ...