Statistical computing language and software environment.

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24 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 ...
3
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1answer
98 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 ...
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0answers
59 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 ...
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0answers
87 views

Performing Moran Test using R? [closed]

I’m very new to R so please Bear with me: I have a set of data containing AREA Infested for each region ! and I want to know if there are any spatial autocorrelation between the regions! Here a sample ...
2
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1answer
147 views

Cannot properly import MODIS MOD07_L2 .hdf files into R using rgdal

I've been trying to accurately import and process some .hdf files from the MODIS Atmospheric Profile product (MOD07_L2) in R for several days now. Still, there's something going wrong during data ...
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1answer
101 views

What's the difference in these two shp files?

I'm trying to plot points on these maps in R, with points from "Coordinates" in the same folder. The WL.shp plots fine with the data, but the NG.shp (which should only be larger and of the same area ...
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1answer
71 views

How to clear areas outside map in R

I succeeded thanks to the eblonde in the disscution (problem with polygon smoothing in R) to smoothing polygons in R. Code: inter1= read.table("c:/inter2.csv", header=TRUE) #add a category ...
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24 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 : ...
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50 views

Neighbours list extracted out of polygon regions

I've got a SQL database which contains some coded polygon structures. Those can be extracted as follows poly <- data.frame(sqldf("SELECT ST_astext(geometry) FROM table")) The data.frame 'poly' ...
2
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1answer
216 views

How to remove columns in a spatial polygon data frame in R?

My spatial polygon data frame (spdf) contains too many columns (variables) and I want to remove most of the columns entirely. I know how to do this with a regular data frame in R, but I am unsure how ...
3
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2answers
71 views

Counting number of points in particular polygon for list of individuals using R?

I have distribution points for a set of individuals and a file of polygons-with matching IDs. What I would like to do is to go through and for each individual find the total number of points and the ...
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51 views

R package spatstat: How to use point process model covariate as factor when pixel image values are numeric

I am trying to model a point process with an image covariate using the ppm() function in the spatstat package in R. I convert my raster to an im object for use with spatstat, and I run into a problem ...
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1answer
152 views

(R)SAGA: saga_cmd 2.1.0 error? inconsistency?

frequently I am using (R)SAGA, but after SAGA became >2.1.0 the R package is no longer working. The last update for RSAGA was 07/2013. Thus I downgraded SAGA to 2.1.0 (first try was skipping the ppa ...
5
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2answers
441 views

Rgeos drops associated values when intersecting polygons

I am trying to intersect two SpatialPolygonsDataFrames and get a SpatialPolygonsDataFrame as the result. Unfortunately, using the gIntersection function from rgeos (which works impressively quickly ...
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0answers
123 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 ...
5
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2answers
716 views

QGIS affine - form of equation

I am at the mercy of a govt authority who have provided utility information in a cad format with a 0,0 origin and a nonsense grid. About a dozen files, the grid and origin are entirely arbitrary. To ...
3
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1answer
184 views

Polygon fill colour specified by column R spplot

I am trying to plot a geological map using the spplot function in R. For every unit I already assigned a specific color in the col-column of the SpatialPolygonsDataFrame. Now I would like to plot the ...
0
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0answers
90 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 <- ...
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2answers
160 views

projection conversion from mercator to google maps format

Is this spTransform(Finland3, CRS("+proj=longlat +ellps=WGS84 +no_defs+ellps=WGS84 +towgs84=0,0,0 ")) the right way to project a shapefile with this projection coord. ref. : +proj=merc +lon_0=0 ...
0
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2answers
129 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 ...
3
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1answer
345 views

LSA-SAF data reprojection with GDAL and R

The Land Surface Analysis Satellite Applications Facility (LSA SAF) distributes several products derived from the EUMETSAT satellites data. I am working with R to read and process the data (the file ...
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4answers
15k views

How to convert zip codes to latitude and longitude?

I have a data set that includes a list of zip codes. Is there a way in R to convert these zip codes to latitude and longitude coordinates?
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2answers
108 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 ...
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2answers
53 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 ...
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2answers
46 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 ...
17
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2answers
6k views

How can I convert data in the form of lat, lon, value into a raster file using R?

I have a data set of values over a km grid in the continental U.S. The columns are "latitude", "longitude", and "observation", e.g.: "lat" "lon" "yield" 25.567 -120.347 3.6 25.832 ...
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1answer
712 views

Produce raster map using universal kriging as interpolation method

I want to do kriging with external drift(universal kriging) in R. The covariate I use is in WGS84 refrence system. Because of nature of kriging which calculates distance in planar surface I have to do ...
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2answers
402 views

Calculate a polygon around a point - and conver to WKT

The use case I have is this: I want to take points (in my case a data.frame of lat/long coordinates) and calculate a polygon around each point of a given radius (in km, miles, whatever). To be clear, ...
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0answers
49 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 ...
3
votes
1answer
42 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 ...
3
votes
1answer
214 views

Given a Lat and Lon, identify if the point is over land or ocean?

In R, what is the quickest way to identify if a point is over land or ocean? e.g. for: set.seed(0) lat <- runif(10, -80, 80) lon <- runif(10, -180, 180) points <- expand.grid(lat, lon) ...
7
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3answers
193 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 ...
1
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1answer
27 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
42 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 ...
2
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0answers
70 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 ...
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0answers
79 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 ...
3
votes
1answer
4k views

Convert a shapefile with northing/easting to ASCII raster with latitude/longitude

Linked below is a polygon shapefile whose projection is NAD83 and whose values are LU/LC codes. Coordinates are meters of northing and easting. I would like to convert it to an ASCII raster with ...
13
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2answers
3k views

Using R with ArcGIS Desktop

In response to comments below, a re-phrasing of the question. I've used the integration of R with QGIS, and found it a very uesful tool. Having taken a look at the R toolbox extension for 9 and the ...
10
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3answers
271 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 ...
7
votes
1answer
491 views

How do I call 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 ...
3
votes
2answers
160 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
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0answers
30 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
63 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
42 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 ...
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0answers
26 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
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2answers
469 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
71 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
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1answer
137 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
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1answer
52 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
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1answer
79 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 ...