Statistical computing language and software environment.

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0
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1answer
35 views

Finding neighbors for non adjacent polygons in R [closed]

I'm looking for a method or function in r-project that create a neighborhood matrix from a group of polygons that don't touch each other, like polygons of set of blocks separated by streets in a town. ...
0
votes
1answer
54 views

Creating SpatialPolygons in R

I am trying to do kriging with my data. But there is a problem here. I want to use krige command in gstat package. But I do not have "Spatial object with prediction/simulation locations". How I can ...
2
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1answer
15 views

Retain “region” elements for when using fortify() on a SpatialLinesDataFrame

I'm layering multiple plots using ggplot2 to create a map of Alaska that combines school location and the major road network. I've learned that despite being labeled "major roads" there is wide ...
11
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2answers
5k views

Aggregating points to grid using R

I have a question with regard to spatial aggregation in R. What I am trying to do is aggregate a point dataset to a grid. I am unsure however how to do this as I have little experience with this sort ...
0
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3answers
79 views

Converting position data created in R to GPX format?

Does anyone know if there is a way to convert position data (latitude and longitude) created in R to GPX format to use with navigation software? I have been searching and havent found an answer. ...
3
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0answers
234 views

Using R to map matching GPS data? [closed]

I have many vehicles GPS data points, which consist of "timestamp, longitude, latitude, fuel consumption and distance" and the data is OSM(open street map) based. I want to match the data points to ...
0
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0answers
23 views

Problems to export raster files in R software

I'm working with R software with raster and netcdf4 packages adn netcdf files to get information from SST. I got the information and now I'd like to convert in ascii or geotiff files to work in ArcMap ...
1
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0answers
27 views

Polygon to Raster: Cells with multiple values

I'm trying to use R to rasterize a number of shapefiles and I'm having trouble dealing with cells on the edge of shapes, in other words the if a cell is partially covered by an NA value and partially ...
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0answers
44 views

north arrow outside map

I am plotting 5 maps using spplot having a 2*3 layout. The space not used for maps should contain cartographic features such as a north arrow. Could someone guid me in the right direction? I know how ...
2
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1answer
75 views

Create GPX track in R. writeOGR function

I have a gpx file where someone exported two different activities in two separate locations to a single track. I need to split them and avoid getting the erroneous line in the track layer that ...
7
votes
1answer
106 views

How to decrease the distance between legend's items in R?

I'm trying to create correct choropleth() map in R using GISTools package. I use choro.legend() to display my legend. However I can't create either correct legend placement, AND/OR I don't understand ...
1
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1answer
41 views

csv points into raster using R

I have got the forest cover data of a region in africa (raster layer) and some data collected inside this region by a survey (.csv). In the .csv file I have got x,y coordinates and 3 other columns ...
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0answers
15 views

Why the krige.cv gstat function does not ask for a semivariogram model for every training set?

I'm performing kriging leave-one-out-Cross-validation with the krige.cv gstat function: Is it possible to specify the semivariogram model for every training set? or is there a reason why the model has ...
-3
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1answer
57 views

How to colour a SpatialLinesDataFrame with Rainbow

how to color a SpatialLinesDataFrame according to some given value (Rainbow) FRA=readShapePoly("FRA_adm0.shp") grid <- raster(extent(FRA)) # Choose its resolution. I will use 2 degrees of latitude ...
0
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1answer
61 views

R: Voronoi tesselation from long/lat data?

I want to create a SpatialPointDataFrame and Voronoi Tesselation from my .csv data downloaded from EPA, available here: http://uloz.to/xboQc7cu/no2-calif-csv I convert my data in SPDF format in 2 ...
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0answers
26 views

R: how to correctly set number n for sample grid for IDW?

I'm trying to make IDW in R. In my tutorial, I found this approach which is easily understandable, expect of one point - why they used n = 6000 ??? how did they established the value to create a grid ...
0
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1answer
94 views

Adding shapes and/or icons to legend using Leaflet within R?

Is it possible, using Leaflet within R, to make a legend in such way that includes a set of icons or shapes and their corresponding value?
2
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0answers
35 views

Filtering Small Areas of Shapefiles Using R

I'm trying to use the method proposed by the @ialm in the Question "How to speed up the plotting of polygons in R?" There, he loads the maps using getData from the raster package, I tested and it ...
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0answers
17 views

Use SVM to make prediction based on two Raster input in R

Right Now I have two raster images, one is elevation another one is slope. And I already generate a SVM model in R. Right now I want to use this SVM model to make a classification prediction using the ...
1
vote
1answer
78 views

dynamic visualization of spatiotemporal data on a grid

I am handling spatiotemporal data and it is a quite new area for me. Basically I have data related to the position of cars at a given time in Montreal. I would like to dynamically visualize the ...
1
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0answers
29 views

Specifying the “idp” and the “nmax” in the krige.cv function

I'm performing IDW interpolation using the idw R function from the gstat package. For the purpose of determining what combination of "idp" and "nmax" produces the lowest RMSE in leave-one-out-cross ...
18
votes
6answers
8k views

Working with PostGIS data in R?

I work with R almost all the time, and now I am using it for doing spatial data mining. I have a PostGIS database with (obviously) GIS data. If I want to make statistical spatial analysis and plot ...
1
vote
1answer
36 views

How to deal with two dimensional lat and lon variables in a NetCDF file in R?

I'm trying to convert a NetCDF file to a dataframe in R using the RNetCDF package. The NetCDF file is very different from what I have experience with, in that the lat and lon values each have two ...
43
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9answers
19k views

Tutorials to handle spatial data in R?

Does anyone know some good tutorials to handle spatial data in R? I know that there are some packages like rgdal and maptools but I haven't actually found usefull tutorials to get in touch with the ...
3
votes
2answers
131 views

Plot tilted map in R

I would like to plot a tilted map, similar to the image below. I would prefer to do this using ggplot2 but I'm glad if there is a solution using base R. Any ideas on how to do this? Here is a dataset ...
8
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6answers
10k views

how to overlay a polygon over SpatialPointsDataFrame and preserving the SPDF data?

I have a SpatialPointsDataFrame with some additional data. I would like to extract those points inside a polygon and at the same time, preserve SPDF object and its corresponding data. So far I've ...
0
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2answers
420 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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0answers
14 views

Raster Values converted to 3.4e+38 in R

I have read a .grd file into R as RasterLayer which should only contain 1, 0 and NA as cell values. Turns out all the NA cells contain 3.4e+38 as value now. How can I change that and why does this ...
0
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0answers
36 views

R: why are missing choro.legend() items when displayed in zoom()? RStudio

I wish to create map of Oregon, using choropleth(). Using locator() trick I've revealed coordinates for my choro.legend() position. It seems correctly placed in my plotting window, however my legend ...
1
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0answers
38 views

Raster package limitations

I am very new to R and to raster package and I was hoping that someone could provide some guidance. I am trying to run a function that averages a series of rasters, 300 to be exact, they are in geotif ...
0
votes
1answer
29 views

Calculating the number of days above freezing in R

Im wondering if anyone has come across any data source that can be used to calculate the number of days where temperatures are greater than 0 degrees C, 10 C and 20 C at a global scale? I have a site ...
0
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2answers
47 views

How to check my EPSG and units in R when it is not defined in proj4string?

After reading my .shp in R using readOGR(), I tried to figure out what is my EPSG and what are my units in my projections? when I tape my.shp = readOGR(dsn=setwd(dsn = dsn, my....
2
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0answers
41 views

Error mapping data frame in R: is.data.frame(map) is not TRUE [closed]

I am trying to generate a map using the following data and code: fileURL <- c("https://drive.google.com/open?id=0B-jAX5hT2D3hNnVtLVhROENKRGs") require(data.table) require(tidyr) require(dplyr) ge....
1
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0answers
11 views

Using 'Index-type' raster layers with negative values as independent variables in a multiple linear model in R

Using a multiple linear model I am trying to quantify the "effect" of abiotic landscape characteristics (slope, elevation, solar radiation, and a load of terrain indices) on vegetation greenness (NDVI)...
1
vote
1answer
82 views

R kriging in QGIS

I'm trying to work with the R Kriging script in QGIS (processing toolbox). I have installed R before directly to C:. I also have installed the packages raster, rgdal, sp and automap. When I'm starting ...
0
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0answers
27 views

Extract raster values from RASTERSBRICK using XY coordinates falling within each polygon R

I have a rasterbrick s (10000 raster layers) that actually is a time series raster. Accompanying s is a SpatialPolygonsDataFrame with many sub-polygons which can be identified by names and/or IDs etc. ...
1
vote
1answer
122 views

Programs/ languages to process netcdf files “fast”

I am using R to loop through thousands of NetCDF files (downscaled climate data), and while I am able to do it using R, the code is too slow. I am looking for a way to speed it up and to maintain ...
1
vote
2answers
788 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 ...
7
votes
4answers
11k views

Converting osm file to shapefile (or data frame) in R

I was looking for a road shapefile for Australia today. I ended up going to Geofabrik. Open Street Map has data in .osm format. But they do not have one in .shp for Australia. If possible, I want to ...
3
votes
1answer
35 views

Is it possible to start the GRASS GUI from R?

I am using the rgrass7 package in R in order to work with GRASS GIS. After having set the needed enviornment variables, I can now launch a GRASS session from R and and work on my GRASS data using ...
1
vote
1answer
44 views

Using 'sp' method to subset SpatialPointsDataFrame with SpatialPolygon returns error in parLapply()

I have numerous very large data sets of ship tracking data (Automated Information System; AIS). These are originally in a file geodatabase and can be downloaded here (this is a smaller file for ...
0
votes
1answer
29 views

Get feature type of a layer

I have to assign the feature type of a layer. Does anyone know an function, or way to access this information. I have noticed that the message of the function readOGR (package rgdal) contains an ...
2
votes
0answers
49 views

Is there an R package for finding the maximum-area rectangle in a non-convex polygon?

Does anyone know if there is an R package out there with an algorithm which finds the largest rectangle within non-convex polygons? I have Googled, searched the R Sig Geo archives, and looked here on ...
0
votes
1answer
25 views

histogram of raster coordinates in R

I'm trying to generate an histogram of the y coordinates where raster values are 1. Mysteriously the following, different rasters, give me the same histogram. What could I be doing wrong? here are ...
0
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1answer
93 views

Creating polygonal windows for spatial analysis in r

I am attempting to normalize a spatial point pattern using a population density raster in r. My problem is that the function I am trying to run is recognizing the "white space" around the raster I am ...
31
votes
4answers
39k views

How to open a Shapefile in R?

I need to open a shape file from ArcMap in R to use it for further geostatical analysis. I've converted it into ASCII text file, but in R it is recognized as data.frame. Coordinates function doesn't ...
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0answers
52 views

Clipping raster brick object in R

I have MODIS NDVI TIFF files for a year I want to first clip it with a irregular polygon (not by its extent only) of my study area and save it as a multi band raster in TIFF format The TIFF image are ...
9
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3answers
3k views

r - increase speed of crop, mask, & extract raster by many polygons

I'm extracting the area and percent cover of different land use types from a raster based on several thousand polygon boundaries. I've found that the extract function works much faster if I iterate ...
3
votes
3answers
165 views

Converting SpatialLinesDataFrame to SpatialPointsDataFrame in R?

In R I have a SpatialLinesDataFrame (for example from a coastline shapefile) and I want to convert it to a SpatialPointsDataFrame. I want to keep all the vertices from the line shapefile to become ...
1
vote
1answer
51 views

How do I get rid of edge effects while using focal in R to smooth a raster?

I am trying to use R with the focal function from the raster package to smooth raster images. I am working with Radar images that have already been preprocessed. As part of that, some calculations ...