Statistical computing language and software environment.

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2
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0answers
119 views

Calculate Euclidean distance to raster WITHIN multiple polygons

I am using ArcGIS 10.1 on a Windows x64 system. I am working in a study area where I have 360 000 locations of about 50 territorial animals. I have a shapefile containing 125 sometimes overlapping ...
2
votes
1answer
79 views

Whats the best way to convert this tab data to a raster?

I have some grid data that is stored in a xls file. The rows are lattitude and the columns are longitude values in decimal degrees (see image). What would be a quick and efficient way to convert ...
2
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1answer
27 views

Converting character attribute to numeric attribute

I am following the very simple code found in this question Converting shapefile to raster: Character attributes to create a new numeric variable based on a factor. My proble is that the new numeric ...
0
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0answers
69 views

gpclib package in R

I'm trying to do a locoh run on R version 3.1.2. Since the gpclib package is depreciated, I've installed and loaded rgeos (the package gpclib has been replaced with). However, the locoh run can still ...
0
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0answers
26 views

KDE looping in GME

I can not get this for loop to run in GME because i is being changed to 1 and , out is not recognized: wd <- "C:\Users\name\Desktop\KDE\2011\"; for (i in 1:15) { ...
0
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1answer
63 views

GME: could not open input point data source

I can not get this for loop to run in GME because i is being changed to 1 and , out is not recognized: wd <- "C:\Users\name\Desktop\KDE\2011\"; for (i in 1:15) { ...
0
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1answer
86 views

For loops + boxplot for raster

I have several Rasterstacks (b1_mask, b2_mask,...) of several layers representing only a determined pixel-intensity range. (So point "A" in some layers is "NA" - in others a "value" of that certain ...
2
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2answers
66 views

Create lines from polygon borders with polygons attributes

I have a shapefile of polygons that border each other perfectly, each with a numerical attriubte. I'd to create a shapefile of lines, where every line is created from the border between two polygons, ...
0
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1answer
48 views

Extent from Centroids, Projection, and Resolution?

I have a file that defines a raster, although all the metadata was lost. I know the lat/long coordinates of the grid centroids, and that the grid is in a Mercator projection with a 1/12deg equatorial ...
3
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0answers
43 views

Subset two rasters with different extent and origin (and resolution) only where there are data in both in R

in R, I have two rasters with different extents and origins (and possibly even resolution). How to efficiently take the subset of each of them only where there are data in both of them? Here is a ...
1
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0answers
97 views

How to extract percentage of land cover from a raster according to multiple shapefiles?

I have a raster map that represents land cover of a region, and different shapefiles (total 120) in the same region. I want to know the percentage of every land cover for each shapefile. For example, ...
1
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0answers
45 views

Identify nearest neighbor in grid in R (spatial)

I would like to create a square grid and identify the grid cells that border a set of other grid cell for which a binary variable takes a 1. In the following example, I would like to generate a vector ...
0
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0answers
70 views

R using fortify to project shapefile on google map gives wrong results

I have a shapefile that looks like this > str(FieldsMap) Formal class 'SpatialPolygonsDataFrame' [package "sp"] with 5 slots ..@ data :'data.frame': 3 obs. of 2 variables: .. ..$ id : ...
1
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1answer
83 views

Export to images subsets of Spatial Points Data Frame

I have a csv file, which I converted it to Spatial Points Data Frame. And I want to split the spatial data and export each map to a jpg file. I did the following: SB <- read.csv("SB_040914.csv", ...
0
votes
3answers
573 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 ...
0
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0answers
52 views

Spatial regression lag on dependent and independent variables in R

I have a SpatialPolygonsDataFrame with summarize data about some regions. How can I make a spatial regression with lag both in the independents and dependent variables in R, like this: Where y is ...
2
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2answers
193 views

In ESRI ArcGIS, is there an equivalent to the RStudio Console Windows?

UPDATED I know ESRI provides scripting capacity, via the Python window, but I've had a hard time with it. Making the jump from the Field calculator to the Python window was too much to me. Trying to ...
2
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2answers
111 views

Is there an R equivalent of NEAR in ESRI ArcGIS?

I have 54 points in one data set A I have 300+ data points in a dataset B. I wish to find the distance for each point in dataset-set B, to points in dataset A. Nearest Neighbor packages appear to ...
3
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1answer
78 views

comparing and finding inaccuracies in two raster layers

I have two raster layers with urban cells and rural cells. I used an overlay function to compare these two raster layers and see the differences. Before overlaying I gave urban cell the value 1 and ...
1
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2answers
82 views

projection differences in R

I am trying to reproject some climate data that I downloaded from http://gdo-dcp.ucllnl.org/downscaled_cmip_projections/dcpInterface.html#Welcomein The BCSD-CMIP5 data is found under the tab ...
1
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0answers
74 views

How to define the output raster resolution when rasterizing a vector?

I have a vector file which I want to rasterize and adjust its resolution to the reference map, in QGIS. I tried spatial_sync_raster function in R to set all the rasters into the same resolution as ...
1
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1answer
40 views

gTouches error without geometry error?

I have a map showing administrative boundaries (available here). I've loaded it into R and have attempted to run gTouches (from rgeos) to determine which areas are adjacent to which, but receive an ...
2
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2answers
355 views

combine rasters into single raster with multiple field values in R

I have several raster brick objects that I would like to combine into one raster with multiple field values for each cell, but I am not sure how to do this in R. For example, let's say I have two ...
7
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3answers
228 views

Best way to make a fake hillslope?

Anyone ever have to make a fake hill slope? or a fake digital elevation model (DEM)? What are the best methods for doing so? For more specifics, suppose I wanted to make a fake hill slope, that was ...
3
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0answers
80 views

kriging of compositional data (grain size)

I have posted this already in the GEONet Forum but without any suggestions, now I am hoping for some feedback here: I have a problem concerning interpolation of compositional data of grain sizes. I ...
0
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0answers
144 views

Creating the Regions based on spatial clusters

I need to create areas for my shapefiles for spatial analysis for each. So I have a number of stations and I created 5 clusters based on the distance. code: Al <- ...
2
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0answers
137 views

Raster to polygon using R [closed]

I am trying to convert a raster object to a polygon object using R but I am running into some problems using my Windows 7 machine. I originally tried to use rasterToPolygons (package: raster) but it ...
2
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0answers
70 views

How to split a polygon into quadrants in R/Qgis?

I am solving the same problem as How to split a polygon into quadrants?, except that I am looking for a solution in R or QGis. So I have a polygon layer shapefile, which is unfortunatelly not exactly ...
1
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0answers
38 views

Unexpected Moran's I value in R using a chessboard example

I'm running into unexpected values for Moran's I when using the Moran.I function in the R library "ape". My understanding is that a chessboard is an example of perfect negative spatial ...
10
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3answers
322 views

From polygon to continuous measure of diversity?

First of all; I have tried to find a similar question, without success. Maybe it's because I'm quite new to GIS and I don't really know what exactly I'm looking for. If someone points me to a similar ...
4
votes
1answer
312 views

Convert coordinates from readShapePoly in R to long-lat coordinates

I'm trying to find some centroids of a shapefile for Danish municipalities and afterwards find the driving time between them. I use R's readShapePoly function from maptools combined with the ...
2
votes
1answer
71 views

clustering map (North, Centre, South) in R

I am looking for a method to partition map in 3 groups (North, Centre, South) like this: how to do this in R please stations.txt Code : Al <- shapefile("DZA_adm/DZA_adm0.shp") # read in ascii ...
2
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0answers
97 views

How to merge an excel file with a shapefile in r

I am new to mapping in R so my question might look trivial. I want to have a density map of US for number of phone calls for different areas. Each area includes some zip codes. I only have number of ...
1
vote
1answer
224 views

Legend and coloring of markers with plotGoogleMaps in R

I have a data frame (X) that looks like this: code cluster name longt latit 101 1 A -89.6171 35.24992 105 1 B -90.0154 35.10510 106 2 C ...
1
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0answers
54 views

How to solve coordinate differences between packages

I have two maps generated by two different methods. The first, I used maps package and the function map() and symbols(). On the other hand, I used the ggmap package with the ggmap() and geom_point() ...
3
votes
1answer
174 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
vote
1answer
41 views

Aggregate table with dates and average geographic coordinates

When SOG is 0 Stops gets 1. When the next SOG is 0 then Stops gets 2 and like this consecutively. Now I want to group all the rows where SOG != 0. The trick is that I should have the following ...
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0answers
91 views

Assign CRS to shapefile in R

I imported my shapefile dat to R with readOGR, coordinates are given in easting and northing, I'd like to change it to latlon and tried: dat_latlon <- spTransform(dat, CRS("+proj=longlat ...
1
vote
1answer
111 views

R geographically weighted regression GWModel

I am exploring the use of GWmodel to run some GWR regressions. I set it up and tried to run some sample regressions using the gwr.basic function, but ran into the following error, Error in t(X * W.i) ...
1
vote
2answers
145 views

Extract values from raster into points: data loss using extract function from raster package

I am trying to extract values of raster cells on points using extract from raster package in R (similar to 'Extract Values to Points' in ArcGIS-10.2). After doing so in order to check integrity, I ...
0
votes
1answer
271 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 ...
1
vote
0answers
167 views

How to prevent cross-world lines in ggplot world map?

I'm having issues displaying 'great circles' paths and polygons in ggmap, an extension of ggplot2. Please enter the following code to replicate my issues: ...
5
votes
1answer
162 views

Cell declustering using open-source software

I want to perform cell declustering in a small point data set. I have 9 observation points and I want to find the size of the region of influence for an observation, and afterwards use that as ...
2
votes
1answer
161 views

Export band names with NetCDF file in R

I am using R to work with multiband raster files and am running into a problem. I have named the bands, but when I export in netcdf format, the band names are being stripped. Anyone know how to ...
2
votes
1answer
96 views

average certain raster cells in R

If I have two rasters, let's say x1 and x2, that are the same dimensions, how can I take the average of the two but only where both have data to have a third raster x3 that is a composite of the first ...
2
votes
2answers
88 views

Is there a county-level maps dataset that includes independent cities in virginia?

and thank you in advance for your help. The following code shows the dataset I am working with: library(maps) CountyMapData <- map_data("county") head(CountyMapData) long lat group ...
4
votes
3answers
94 views

How can I snap one set of points to another in R

I would like to snap one set of points (SpatialPoints* objects) to another in R using Euclidean distance. I'm hoping for a function like maptools::snapPointsToLines. The attributes of the points ...
0
votes
1answer
315 views

R custom color theme in levelplot

R range(diffRain) [1] -2.59 7.59 How can I code a color ramp following ways? red color ramp less than 0.0 blue color ramp greater than 0.0 This is a part of my code. myTheme <- ...
6
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3answers
437 views

1km circles around lat-long-points in many places in world

I have hundreds of lat-long-points spread around the world, and must create circle-polygons around each of them, with radius exactly 1000 meters. I understand the points must first be projected from ...
1
vote
1answer
253 views

Creating new shapefile after merge operation using unionSpatialPolygons

I only recently started playing with shapefiles and R packages for manipulating them. I am looking at creating a new shapefile based on merged polyons by following this example, however, I cannot seem ...