Statistical computing language and software environment.

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2
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2answers
185 views

R - What is the purpose of .GAL lattice file?

Could someone please explain to me what the purpose of a .GAL lattice file is? I want to see if my data are spatially autocorrelated and I've been following Bivand (2013). I have loaded my polygon ...
1
vote
0answers
41 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
votes
1answer
121 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 ...
0
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0answers
64 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 ...
1
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0answers
99 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
votes
1answer
279 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 ...
1
vote
1answer
102 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 ...
0
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0answers
67 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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0answers
67 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
votes
1answer
426 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
votes
2answers
108 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 ...
1
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0answers
84 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 ...
1
vote
1answer
223 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
votes
2answers
543 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 ...
1
vote
0answers
141 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
votes
2answers
798 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
votes
1answer
391 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
136 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 <- ...
0
votes
2answers
166 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
votes
1answer
424 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 ...
7
votes
4answers
19k 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?
2
votes
2answers
181 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 ...
1
vote
2answers
73 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 ...
2
votes
2answers
87 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 ...
1
vote
1answer
766 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 ...
1
vote
2answers
551 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, ...
1
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0answers
71 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
68 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
262 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
votes
3answers
222 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
vote
1answer
36 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
votes
2answers
257 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
119 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 ...
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
votes
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
votes
3answers
310 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 ...
3
votes
2answers
200 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 ...
3
votes
0answers
72 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
70 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
64 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
34 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
579 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
243 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
223 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
85 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
129 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
93 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
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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() ...
2
votes
2answers
285 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) : ...
2
votes
2answers
525 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 ...