Statistical computing language and software environment.

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Problem in creating neighbors, area and perimeter in spatial econometrics using R

I’m working on a spatial cross section model with R-programming-language. I’m running these codes which refers to anselin data (spatial_columbus) in spdep package. I found them from these links: ...
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38 views

Doing joint hypothesis test in spatial regression using R?

I'm doing estimation of spatial lag/error model using R package "spreg"/"spdep" but I cannot find any method to do anhypothesis test after regression. For example, I want to test whether two ...
5
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2answers
676 views

Reduce the resolution of a shapefile in R (or QGIS if necessary)

I'm using shapefiles of history U.S. state boundaries from NHGIS to make maps in R. These shapefiles are much higher resolution than I need when making maps at the scale of the country: over 2 million ...
4
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1answer
131 views

Why covariance values are different in R and ArcGIS?

I've calculated covariance between 7 rasters using R and ArcGIS. It gives me different results. Each times covariance values from R are approximately 1.874 times higher than ArcGIS values. R - ...
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1answer
462 views

Route analysis in R based on the OSM transport network: possible?

I'm analysing the likely paths taken by commuters on their way to work, based on Census flow data, job density distributions and the transport network. At the moment I'm using pgRouting and the ...
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2answers
1k views

How to Find the Average Raster Value of an area defined by a shapefile using R?

I have a set of raster images which represent a specific month over the years, and I want to make a timeline of the average values of an area using a shapefile. How do I extract the values from the ...
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2answers
214 views

Avoiding R for windows gui front-end has stopped working error?

I am trying to load huge number of points (shape file) in R. But when I load it, the program displays following error message and just stops. "R for Windows GUI front-end has stopped working" My OS ...
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1answer
67 views

How to create header files for multiple rasters in R

I have nearly 1000 generic binary images, i.e., headerless, band sequential and binary (16-bit signed integer). I have been succesfully able to load these with package 'raster' only when I create an ...
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1answer
125 views

Why Stacking rasters return all values as NAs?

I have several rasters that I want to do some calculations ,basically calculating the moving average. dir2 <- list.files("D:\\2010+2011", "*.bin", full.names = TRUE) ...
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1answer
58 views

Adding a grid and selecting random cells from spatial polygon in r

I have a fairly similar question to this: Similar Question I am working with a map of Denmark or more a subset of a Denmark Map. This file comes from the Global administrative areas site GADM site ...
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2answers
456 views

Iterating polygons on a SpatialPolygonsDataFrame in R with readWKT

I have fetched some data (39 objects) from my PostGIS database and converted this data into a matrix: rs <- dbSendQuery(con, "SELECT ST_AsText(polygon_accumulation) AS ShapeWKT from ...
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1answer
66 views

How to get specific coordinate system to get arcGIS point shapefile in r?

I have a Point shapefile from arcGIS 10. I want to get it in r and also want to get it a specific predefined coordinate systen for my data. I can read the shapefile in R but summary in r Shows ...
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1answer
90 views

Extract single datapoint from netCDF file in R using ndcf

I'm trying to extract a single variable from a 3-dimensional netCDF file. [1] "file blah.nc has 3 dimensions:" [1] "longitude Size: 200" [1] "latitude Size: 100" [1] "time Size: 2000" [1] ...
4
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1answer
143 views

Convert ESRI Shapefile to Raster using R - biggest polygon area to raster cell value?

I want to create a raster from an ESRI shapefile. Multiple polygons may exist in one raster cell. If so, I want to assign the attribute variable which occupies the biggest area of the raster cell. ...
4
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2answers
72 views

Map location of unknown point with distances to two known points

I'm trying to develop a function in R that will locate a point (A) on a map given distances between that point A and two other points (B and C), for which exact coordinates are known. The problem I'm ...
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2answers
66 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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0answers
152 views

Moving point on OpenStreetMap route

Basically I generate random numbers in R language which are indeed times between bus arrivals. I need to simulate a moving point(a bus) in OpenStreetMap by using this generated numbers. I have read ...
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58 views

Rounding off coordinates in an SpatialPolygonDataFrame in R

EDIT AFTER COMMENTS After a comment of Whuber (Thank you!) I realized it will probably be most easy to incorporate a round(...) statement within my code to be able to work with less decimals. ...
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1answer
39 views

How to batch export using r.out.gdal command in GRASS

I created a list of files (NPPFILES) using g.mlist command in GRASS 7. Now I would like to export these files as .tiff files. I tried this command in GRASS prompt for files in $NPPFILES; do ...
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2answers
242 views

Create Raster file in R from Matrix and latlons

I could use some advice on how to create a Raster file in R with a Matrix of data points and the coordinates stored in a separate file. Both, data and coordinates come from a NetCDF file. I extracted ...
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61 views

Calculating surface and lines in 3D projection in R

For my internship research I am trying to compare the surfacearea and length of geometric shapes and lines in one coordinate system to another. I have a SpatialPolygonDataFrame in the European equal ...
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42 views

How to reference a number variable in r.mapcalc within QGIS graphical modeler

I need to run the following formula in r.mapcalc: (xor(abs(A-B),abs(A-C))>120)*A I would like to however use a user defined number input variable instead of the 120. I already have this variable ...
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28 views

Calculating average raster values around set of points using ArcGIS for Desktop (or R)? [duplicate]

I have a 30-m elevation raster as well as a set of points that overlay the raster. For each point, I want to calculate the average elevation within a 5-km radius of the point. One way I was ...
2
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1answer
64 views

Is this a known issue in gaps between masked raster and spatial polygon in R with mask command?

This is my codes raster file: RAD polygon(shape): ws_sfc RAD.sub <- crop(RAD, extent(ws_sfc)) plot(RAD.sub) RAD.sub <- mask(RAD.sub, ws_sfc) plot(RAD.sub) plot(ws_sfc, add = TRUE) ...
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18 views

Kernel Density Analysis using R and ArcGis [duplicate]

I am doing some Kernel Density Estimations, and like everyone elese I face difficulties with setting the bandwidth to create georeferenced rasters. ArcGis (10.1) does it just fine, but it has no ...
2
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1answer
107 views

Plotting species distribution on map in R

I'd like to plot the distribution of a species on a map of Switzerland, following this tutorial. library(maps) library(mapdata) map('worldHires', 'Switzerland', xlim=c(5, 12), ylim=c(45,48)) From ...
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106 views

Unable to access R from QGIS 2.4

I have been unable to run R from within QGIS on my computer. I have R version 3.03 installed and QGIS 2.4 on Windows 7. R is located at C:\Program Files\R\R-3.0.3\bin\and this is the path e specified ...
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38 views

QGIS using different R lib

I am working with a colleague who is learning QGIS and has a question about the R plugin. His library path (.libPaths()) has two folders: "C:/Users/RDCERWAW/Documents/R/win-library/3.0" "C:/Program ...
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3answers
222 views

Import shapefiles on my postgis table using R

Using R, I would like to import shapefiles that are in a directory on a geometric table i have on postgresql / postgis. What is the instruction that allows me to do it? EDIT: here is my code to ...
2
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2answers
226 views

MODIS Level 1B batch process

I am a new MODIS Level 1B user. I have been using the MODIS Swath tool to process my images. However, I have over 1000 images to process. I was wondering if there a script available in IDL or R (very ...
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70 views

Using R to subtract the polygon area of one shp file from another

I'm looking to produce a map from two separate maps in R. My Maps files are as follows: ftp://ftp.cpc.ncep.noaa.gov/GIS/us_tempprcpfcst/610prcp_20140822.zip #Map1 ...
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1answer
51 views

going from hillshade to percent shaded (gdaldem)

I assumed hillshades output percent shaded (scaled to 255) at the given azimuth and altitude but this is incorrect. A flat raster at 80 degrees altitude has a maximum value of 251 instead of 255. How ...
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2answers
114 views

How to produce “SpatialPixelsDataFrame” from stacked RasterLayer?

How to produce "SpatialPixelsDataFrame" from staccked RasterLayer ? I have a stacked rasterlayer and I want to convert them to SpatialPixelsDataFrame. RasterLayer information is > RAD.all[[1]] ...
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1answer
155 views

create the postGIS table error No such driver: PostgreSQL

I'm trying to create the postGIS table with spatial features I can do it by: library(RPostgreSQL) library(spacetime) library(rgdal) dbname = "geodatabase" user = "postgres" password = "***" #password ...
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1answer
230 views

Step-by-step: How do I extract Raster values from Polygon overlay with Q-GIS or R?

I am writing my master thesis at the moment and am having the exact same problem as user Curley in this question: I first need to overlay a Corine 2006 raster with a polygon layer (2638 polygons). ...
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2answers
141 views

R -plot 12 images per plot or save 12 images per image file in R

Here is R script and my question is How can I plot 12 images per plot or save 12 images per image file because I have total 864 images. RAD1998 <- raster(paste(getwd(), "/1998bil ...
2
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1answer
123 views

Levelplot(RasterVis) two marginal plot scale?

How can I add/display scale to two marginal plot? RAD1998.all <- stack(list.ras) list.files <- mixedsort(list.files(paste(getwd(), "/1998bil/", sep = ""), full.names = F, pattern = ...
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2answers
142 views

How are kappa and overall accuracy related with respect to thematic raster data?

I recently calculated kappa (using confusionMatrix{caret} in R) between a thematic raster dataset at 1m spatial resolution and another at 30m spatial resolution. I was interested in quantifying the ...
2
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1answer
74 views

How to assign CRS to RasterLayer in R

I have a layer with coord. ref. : NA. How can I assign coord. ref. : +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0 to coord. ref. : NA? class : RasterLayer dimensions : ...
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3answers
240 views

How to compare spatial patterns (crime cases vs population)?

I am looking for a way to statistically compare two spatial patterns in shape polygon data (not point pattern analysis). Let's say I have a city map divided in neighborhoods (barrios), in shape ...
2
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1answer
36 views

How to read ASTER metadata in IDL?

I'm trying to read many ASTER images (1B mainly) in IDL (I can try in R also). I'm used to work with Landsat, but the aster metadata is complicated. I write a code with a lots of conditional that can ...
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0answers
78 views

Classical or robust variogram for incorporation into generalized linear model

I'm modeling counts of organisms over time at eleven locations. I'd like to account for temporal autocorrelation in the counts, assuming it's present. As the data are not equally spaced in time, ...
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1answer
2k views

How to perform Random Forest land classification?

This is a follow-up to a previous post: Machine Learning Algorithms for Land Classification. It seems that the Random Forest (RF) classification method is gaining much momentum in the remote ...
3
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1answer
115 views

Max cell value from a stacked raster

How can I find a max cell value from a stacked raster. Rmax <- maxValue(RAD1998.all[[1]]) works fine but Rmax <- maxValue(RAD1998.all[[2]]) gives NA. Of course not in a stacked raster. ...
3
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1answer
92 views

How to overlay a county boundary on a raster file?

I want to overlay California county boundary top of raster layer. Here is is my code: data(coastsCoarse) data(countriesLow) library(gtools) library(maps) library(maptools) library(sp) # Raster ...
3
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2answers
277 views

How to automatically draw lines with a given angle from one single point in qgis 1.8?

I'm new to qgis so please be patient. I need to draw a bundle of lines all originating from the same point and with a 10° angle between each line (e.g. lines bearing at 0,10,20 ..90..110..220..350). I ...
3
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1answer
498 views

How to cluster Raster data

I have thousands of Raster data concerning the ice coverage at the pole at different times (days) over several years. Now I would like to perform a cluster analysis. I want to split the data into ...
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1answer
117 views

Counts the number of points in a polygon in R

I have two classes sharing the same CRS (Latitute and Longitude): bolognaQuartieriMap: a SpatialPolygonDataFrame containing data of a city boroughts. crashPoints: a SpatialPointsDataFrame containing ...
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2answers
438 views

What is the equivalent of arcpy “Con” in QGIS and/or R raster-package?

I'm looking for an equivalent of the conditional expression "Con" from arcpy in an open source spatial analysis package. I'd prefer to use QGIS or R. To provide some additional detail, I need to ...
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1answer
59 views

levelplot index issue

levelplot with static index works fine but not in a for loop. What's wrong with my code? Static index: png(paste("1998",outlist[[1]],".png",sep="")) levelplot(RAD1998.all[[1:4]]) dev.off() ...