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Resources for mapping and displaying spatial data in R

I'd like this to be a repository for all resources available specifically for mapping and displaying spatial data in R. I've seen (and contributed) to this post, but would like this post to focus ...
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635 views

How to process MODIS ndvi data using QGIS/GRASS/R?

I have MODIS ndvi data (MODIS_Grid_16 days NDVI) from the iberian peninsula (3 tiles), from February of 2000 to August of 2012 (really big data). I want to know how to deal with this kind of files. My ...
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2answers
237 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 ...
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97 views

Defining the boundary of a catchment area

I digitized contour lines from topographic maps and created a DEM. With the DEM, I estimated the boundary of a catchment area. Estimated positional accuracy of topographic maps is RMSE = 65 m, with a ...
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1answer
64 views

Matching two point clouds without loss (nearest neighbor, but more complicated)

I have two point clouds, one with demographic and one with electoral data. Points in both clouds represent the same empirical entity (say, a village, or an urban neighbourhood), but are not in the ...
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1answer
180 views

R - Dealing with missing data in SpatialPolygonDataFrames for Moran.test

I'm trying to use Moran.test on a SpatialPolygonDataFrame consisting of 7194 elements in R. I know that there is around 150 polygons with NA values. First I generate a spatial weights matrix: ...
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2answers
221 views

Per-pixel (statistical) calculations on a raster stack using GDAL

In R, it's relatively trivial to perform per pixel calculations based on a raster stack (e.g., get std.dev for each pixel on a 12 layer GeoTIFF). Unfortunately, the speed is less than desirable when ...
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1answer
131 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 ...
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3answers
723 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 ...
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399 views

How to create a loop in R to average ndvi raster time series?

I have monthly ndvi raster geotiffs for multiple years. I need to run a loop to get the average of each of these ndvi grids/rasters. Each of my ndvi rasters contains 143 pixels. I would like the ...
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1answer
56 views

How to infer a relationship between two spatial points using R

I am quite new to the area of spatial statistics, but I'm very interested. For learning and demo purposes, I've created three datsets. Dataset - Persons: This describes individuals at a certain ...
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108 views

Performing cluster analysis in R with Point Datasets

I am a R-Beginner, but I want to use it for some spatial statistics. I want to check the relation between the occurrence of ill persons and the existence of water in a area of interest. To give you a ...
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1answer
219 views

Calling external files in Python Geoprocessing Service

I have created a Python script which calls an R script and then reads the output back into Python. I can run this tool in ArcGIS Desktop (10.2.1) and it works fine. When I publish as a geoprocessing ...
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2answers
496 views

SpatialPointsDataFrame properties and operators in R

I have created an object of type SpatialPointsDataFrame using the sp package in R. However, I am confused about the @, $, . and [] operators and when to use them to access the different properties of ...
2
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3answers
132 views

How to reclassify only a part of a raster but keep the rest unchanged (ArcGIS or R)

I'm trying to reclassify only a certain part of a raster...not the entire raster. Here's the problem. I have a LULC raster of the entire US. There are some issues with the raster that I want to ...
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220 views

Help choosing most suitable bivariate choropleth mapping coloring scheme

I am trying to overlay a nominal variable (2 categories - rainfed vs irrigated) in a choropleth map over a numeric variable. In order to highlight the difference in pattern among the two ...
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1answer
255 views

Convert from eastings and northings to latitude and longitude without ArcGIS

I am not a GIS user, but I was given some shapefiles to work with. I do not have ArcGIS or any other GIS tool, but I do have Matlab with the mapping toolbox and R. From what I can tell, the data is ...
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3answers
72 views

Relative areas projection independent?

I need to calculate how much (in percent) each of thousands of spatial polygons shrink after some events. I use R and the very useful sp-library. Example: Projection: "+proj=longlat +datum=WGS84 ...
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235 views

How can I create a choropleth from the 2010 census ZCTA shapefile using R and ggplot2?

I have created state and county choropleths in R using ggplot2. The method I have used for this came from Winston Chang's "R Graphics Cookbook". For those choropleths the map was already represented ...
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1answer
43 views

linked maps not working in R

I am trying use the micromap package in R, but something is not working. This is the code: library(micromap) library(rgdal) library(ggplot2) setwd ('C:/Users/Jesus/Dropbox/linked maps/Chapter4') ...
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2answers
294 views

What is the latest version of R that supported gpclib?

Does anyone know what the latest version of R that supported the gpclib package? I was using the latest version but when I tried to install gpclib, it said that it was unable due to my version of R. ...
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1answer
59 views

R generated files getting scrambled on import in ArcGIS

I want to put this out there just in case someone somewhere has experienced similar issues. I have a .csv file that I have generated in R 3.0 using this code: ...
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58 views

Dates are off when opening netcdf file in R

I have a netcdf file with the time dimension that goes from 12/2007 until 12/2010 with monthly time steps. I can see the correct dates in both arcgis and panoply. Panoply tells me this file is a ...
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1answer
113 views

Null values coerced to zero (0) when exporting to csv or txt

I extracted values from several rasters, and in some cases, the value is null. However, when I export the attribute table to a csv or a txt file (from ArcMap), the null values are converted to 0. Is ...
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1answer
112 views

How to load Georeferenced Scanned Maps in R

I have a geo-referenced scanned Map in GeoTiff format, which I would like to load into R. My intention is to plot some vector data (points and polygons) over this map using maptools package. Is ...
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2answers
305 views

Processing HDF4 data in R

I am trying to process MODIS files in R, which are in HDF4 format (link to data). I have experience reading in HDF5 and netCDF files in R, but HDF4 seems to be a common problem in R. I am using a MAC ...
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1answer
235 views

how to extract a variable at specific time and depth from netcdf in r

I have the following netcdf file containing 7 variables and 4 dimensions. [1] "file data.nc has 4 dimensions:" [1] "depth Size: 12" [1] "time Size: 37" [1] "x Size: 305" [1] "y Size: 432" ...
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1answer
73 views

shape file for linked micromap not working

I am trying to replicate the example provided in the micromap R package of a linked map with the poverty rate for the 50 US states. I am trying to achieve the same results with a Shapefile from ...
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75 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 ...
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3answers
137 views

How to access shapefile table in QGIS Modeler R scripts?

I need to develop .rsx scripts for QGIS 2.0.1 Modeler to do statistical elaborations on data tables of loaded vector layers. In this case I am not interested in accessing shapefile geometries, I'd ...
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2answers
123 views

Exporting Maps as PDFs in R

In R, trying to export choropleth maps with density and frequency histograms as legends; have had success exporting as an image but not as a pdf. Exporting as an image (.png) works well; the map, ...
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70 views

R: distance from one point to many polygons

OK so I have a spatial polygons data frame, and I have a point of interest. I want to add a row to the SPDF that contains the distance from the centroid of each polygon to this given point. How do I ...
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125 views

Units of gBuffer from rgeos package

I have this polygon: library(maptools); library(sp) setwd(system.file("shapes", package="maptools")) columbus <- readShapeSpatial("columbus.shp") proj4string(columbus) <- CRS("+proj=longlat ...
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2answers
61 views

How to extract values of one point dataset to second point dataset based on proximity using R?

I have to point shapefiles and would like to extract values from one point shapefile to another one based on some measure of proximity, i.e. for any given point in dataset x, extract the mean value ...
3
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1answer
95 views

plotting a SpatialPolygons object using lines() without lines connecting separate polygons

This is almost an extension of a question asked on stackoverflow (http://stackoverflow.com/questions/12196440/extract-feature-coordinates-from-spatialpolygons-and-other-sp-classes), so I'll use the ...
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1answer
129 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
233 views

Flow Accumulation in R

My apologies for such a general question. Is there an ArcGIS like implementation of Flow Accumulation for R? What I am trying to avoid: Using ArcGIS; Using Grass; Using RpyGEO (but will if need be) ...
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67 views

Write raster with its attribute table and symbology

I am classifying lots of rasters and I'd like to automate the legend creation and symbology displaying for easy manipulation. Here is the kind of raster I'm dealing with: library(raster) r <- ...
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1answer
162 views

Is there anyway to stack or merge .hdf files in R Studio?

I would like to be able to merge, mosaic, or stack several .hdf files. Does anyone know the package or library i should be looking for the tool to do this?
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3answers
384 views

How to get count of non-NA raster cells within polygon using R

I've been running into all sorts of issues using ArcGIS ZonalStats and thought R could be a great way. Saying that I'm fairly new to R, but got a coding background. The situation is that I have ...
5
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1answer
426 views

calculate {minimal} distance between polygons in R

I have calculated the surface area of species distributions (merging polygons from shapefiles), but since this area can be comprised of quite distanced polygons, I would like to calculate some measure ...
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2answers
182 views

convert data.frame with no lat-long info to a raster

coders, I need to read in a .txt file into R and later do some spatial analyses on it. I’m working in R. 3.0.2 on a Windows server. I load the following libraries (probably more than I need): ...
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1answer
186 views

Extract points from regular data.frame with coordinates based on SpatialPolygonsDataFrame in R

I have a regular data.frame called datos.merged class(datosmerged) [1] "data.frame" The last two columns are the corresponding geographical coordinates datosmerged[1,c(23,24)] XCOORD ...
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1answer
81 views

Convert point to grid: Numbers of cells differ

In R I am trying to aggregate points data to a grid. The data for the grid (G-Econ) comes as a csv-file. In this file each row represent a grid-cell at 1x1 degree resolution and the given ...
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1answer
193 views

Splitting strings into new rows, retaining geometry

UPDATED BELOW I have 9 shapefiles, each shapefile has 700,000+ rows and I have roughly 12 attribute fields in each shapefile. There are three attribute fields, common to every shapefile, that I am ...
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1answer
177 views

Access Shapefiles from PostgreSQL/Postgis in R

I successfully setup a connection to my PostgreSQL/PostGIS database on Ubuntu Server from my Laptop (Ubuntu 12.04). Therefore I installed RODBC in R to setup a connection and I made a correct entry ...
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1answer
169 views

Sample size for variogram modelling using the geoR package in R

I am trying to use the geoR package in R to model the variogram for a dataset of 15 000 sample points of bathymetry data. I intend to do a random split to create test (20%) and training samples (80% ...
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1answer
180 views

R or QGIS? Measuring elevation at points on DTM surface

Based on answers to this recent question I have been able to create natural looking digital terrain models using a combination of raster, rasterVis and rgl working on data held in ESRI ASCII grid ...
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2answers
129 views

Determine if points fall upstream or downstream from a point on a line (river)

I have a set of fish species occurrences (lat/long) as points and set of rivers as lines. The fish species can of course only occur in the rivers (and not on land). I would like to determine whether ...
3
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1answer
257 views

remove land area from marine region polygons

In my pursuit to merge multiple polygons for the purpose of calculating the surface area of marine species distributions, using shapefiles from Marineregions, I am now trying to remove potential land ...