Statistical computing language and software environment.

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3
votes
2answers
177 views

How to determine in which grid cell each coordinate of an x,y series is located?

I have a circular arena which I have divided into a number of equal-sized 'cells' using a grid-like arrangement of concentric circles and line segments (in grey below) and also a series of x,y ...
2
votes
0answers
38 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 ...
2
votes
1answer
67 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
votes
0answers
48 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
vote
0answers
28 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 ...
5
votes
2answers
507 views

How to stop writeOGR from abbreviating Field Names when using “ESRI Shapefile” driver

I'm currently using the following script to add some attribute data from a table to lots of individual shapefiles: library(rgdal) specieslist <- read.csv("SpeciesList1.txt", header=F) attdata ...
3
votes
1answer
115 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 ...
1
vote
1answer
160 views

How do I convert a .bil (and associated .clr, .blw, .hdr, and .stx) files into georeferenced rasters in R? OR to geotiffs using gdal_translate?

The title says it all. I've got a bunch of .bil files, which I can open in R using the raster command pointed to the path to the .bil file. But I don't know how to efficiently incorporate the ...
0
votes
1answer
58 views

scatterplot of two rasters in R

I am very very new in programming and I want to ask how can I make a scatterplot of two rasters in R and also get their correlation of determination?
1
vote
1answer
100 views

Is it possible to create a scatterplot with icons (svg or png) instead of points

I'm just starting with R and I wanted to know if it's possible to create a scatterplot with custom icons (svg or png) instead of points. I started to import a shapefile, and then I have a set of ...
2
votes
0answers
74 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
0answers
52 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() ...
2
votes
2answers
196 views

Join CSV file to shapefile

I wanted to join a CSV file to a shapefile. When I identified a field to facilitate the join, e.g., map <- spChFIDs(map, as.character(map$ID)) it returned Error in spChFIDs(SP, x) : ...
3
votes
1answer
84 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 ...
2
votes
2answers
439 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 ...
1
vote
1answer
38 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 ...
5
votes
1answer
149 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 ...
1
vote
0answers
64 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
62 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
96 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
92 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
110 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: ...
-1
votes
1answer
148 views

CSV Format change [closed]

Breakline Input File, Breakline Output file I get a breakline file from a CAD guy in below mentioned format. So I am calling this as a “Input” file. I am calling this as a “Output” file. I would ...
7
votes
5answers
3k views

Calculate distance in km to nearest points (given in lat/long) using ArcGIS DEsktop and/or R?

I have two point datasets in ArcGIS, both of which are given in WGS84 lat/lon co-ordinates and the points are spread across the whole world. I would like to find the nearest point in Dataset A to each ...
1
vote
1answer
51 views

How to reproduce contour-style labeling with rasterVis::contourplot?

I am currently working with a digital elevation model (DEM) of Mt. Kilimanjaro, Tanzania. The referring raster grid can be downloaded from DIVA-GIS (Country: Tanzania; Subject: Elevation). After ...
2
votes
1answer
98 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
56 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 ...
3
votes
2answers
181 views

Map accuracy assessment by moving window in R

I would like to make an accuracy assessment using a confusion matrix between classified Landsat image and reference dataset. Maps have the same resolution and extent. I would like to evaluate the ...
2
votes
2answers
62 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 ...
0
votes
1answer
167 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
votes
3answers
335 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
2answers
199 views

Inserting a zoomed-in plot with a full scale plot in the sp package in R

I am using the sp package in R to plot sampled points along a river. However, I would like to zoom in to a sampled area of the entire river, and plot this zoomed area on the full length of the river. ...
2
votes
1answer
123 views

How can i use Kriging inside a Postgis database?

i use a postgis database with temperature data. I want to use a spatial interpolation method but not the supported IDW Method. I need to use the kriging Method. Problem is that its no a part of the ...
2
votes
2answers
158 views

Wrong projection high quality shapefile for the coastline of Helsinki region (Finland)

I did some spatial interpolations in R and I need a support for those. Looking for shapefiles online the best I could find was and it looks really horrible, the same area in ggplot looks like . I ...
1
vote
1answer
250 views

Creating grid polygons from coordinates using R or Python

I have locational data with north-south and east-west coordinates, with a resolution of 100 meters squares. Each data point's location is somewhere within the 100 meters square which centre is given ...
1
vote
1answer
132 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 ...
4
votes
1answer
295 views

Clip polygon and retain data

I have these two polygons: library(sp); library(rgeos); library(maptools) coords1 <- matrix(c(-1.841960, -1.823464, -1.838623, -1.841960, 55.663696, 55.659178, 55.650841, ...
3
votes
0answers
70 views

How to calculate 90% confidence interval in a raster stack

I have a stack of grid files (23) in ASC format from a MODIS sensor and I need to calculate a 90% confidence interval, mean, min, etc, for each one in R, how can I do that? specially the interval. ...
1
vote
2answers
68 views

Count values greater than 0 in SpatialPolygonsDataframe R

I have a SpatialPolygonsDataframe with > 100 layers and I would like to get a single layer showing the total count of where the values of all the layers are greater than 0. I have tried converting to ...
2
votes
1answer
39 views

Randomly distributed cases according to census data

I'd like to randomly place a point within a geographic boundary with the caveat that I would like to use census data so that points are randomly placed according to population density (i.e. more ...
-1
votes
1answer
70 views

conversion of .img to binary file using R

I have a series of raster images which have to be converted to binary files. I request you to suggest a R code for conversion of all files at a time
3
votes
0answers
26 views

How to set m parameter of clusterR function in R?

I want to manage a clustered computation on raster and thus use the "clusterR" function in R (package 'raster'). However, there's a tuning m parameter to set, but the only explanation about this ...
0
votes
1answer
99 views

clipping two SpatialPolygons : Error in RGEOSBinTopoFunc

I want to clip two SpatialPolygons on R without success, I followed the article in the disscution How to perform a true GIS clip of polygons layer using a polygon layer in R? Polygone 01 : > ...
3
votes
0answers
51 views

Algorithm to find the boundary grid points [duplicate]

Let us consider a set S consisting of a collection of grid locations (i,j),i,j=1,\ldots,n, in 2-dimensional gridded plane. Here the point (i,j) corresponds to a rectangular grid in the X-Y plane. ...
2
votes
2answers
124 views

Convert line shapefile to raster, value=total length of lines within cell

I have a line shapefile representing a road network. I wish to rasterize this data, with the resulting values in the raster showing the total length of the lines that fall within the raster cell. The ...
-1
votes
2answers
103 views

Non Matching Rows between 2 txt files [closed]

I need to compare 2 CSV files so that I can get the missing rows from each CSV. All column attributes in each row should match while comparison. So I have 2 txt files and I would like to compare one ...
1
vote
1answer
307 views

Plotting NetCDF file using lat and lon contained in variables

I am trying to plot this NetCDF file (and similar) as a 2d contour map. The file contains a single layer of one variable, "pr". The file has 413x229 X-Y pixel coordinates, and, stored inside the ...
2
votes
1answer
47 views

What can I use for Territory Management in Canada?

For our Canadian organization, I would like to map out the Postal Codes for each sales rep on a map. I've so far used R to pretty good success, but it completely lacks the interactivity I need to ...
7
votes
3answers
2k 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 ...
1
vote
1answer
212 views

NAs not allowed error message in attempt to plot raster object in R

I have imported a clipped raster (performed in ArcGIS 10.1) from the National Landcover Dataset into R, but when I try to plot I get the following error message. Error in .readCellsGDAL(x, ...