Statistical computing language and software environment.

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5
votes
1answer
2k 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
0answers
40 views

Modelling zero-inflated spatially autocorrelated data with extreme values

I have spatially explicit data (above; Longitude, Latitude) with measurements on a random variable (z). This data was not collected in a random or systematic fashion, but instead was recorded ...
0
votes
1answer
190 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 : ...
1
vote
1answer
129 views

Convert shapefile to WGS84 [duplicate]

I have a shapefile with shapelength and shapearea, and would like to convert to WGS84 to use with ggmap. Eventually, I would like to get plot google map of individual regions of the shapefile, and ...
1
vote
0answers
23 views

weighting scheme of gstat for fitting models to variograms

I use R and the gstat package to construct variograms of temperature, and I would like to ask If anyone knows what weighting scheme does the gstat package use to fit a model to the sample variogram?
0
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0answers
58 views

Why does R(gdal) mangle data when converting to geojson?

I've encountered issues with projections in .geojson files created by rgdal, but I never thought it would destroy my data, until I tried this (reproducible example): ...
0
votes
1answer
179 views

Add Points shp attributes to Polygon shp by Point location (as Spatial Join in ArcGIS)

I have a set of points in .shp (ESRI, available here: http://ulozto.cz/xGqRVFrR/voronoi-zip). I would like to calculate Voronoi tesselation from the points, thus create polygons. So far, so good. ...
1
vote
0answers
78 views

rgdal with multiple Feature Datasets in R

I am trying to read shapefiles contained within a geodatabase file (.gdb) into R. The .gdb contains two Feature Datasets with multiple Feature Classes within each. The problem is only one of the two ...
9
votes
2answers
3k views

How to get the second nearest neighbor between two point patterns in R?

Is there a way to get the distances for the second nearest neighbor between two point patterns in R? The spatstat package has a function called nncross but it only applies to the nearest neighbors ...
14
votes
3answers
770 views

How to determine if trees within forest gaps are clustered?

The attached dataset shows approximately 6000 saplings in approximately 50 variable sized forest gaps. I am interested in learning how these saplings are growing within their respective gaps (i.e. ...
3
votes
1answer
635 views

R - How to “smooth” a raster map

I am trying to create a map from raster data. The file came from a crop model, with resolution of 0.5 degree. Even when I disaggregate it (i.e. increase spatial resolution), the map looks really ...
1
vote
1answer
197 views

unsupervised random forest classification in R

I want to compute an unsupervised random forest classification out of a raster stack in R. The raster stack represents the same extent in different spectral bands and as a result I want to obtain an ...
1
vote
1answer
337 views

How to do supervised image classification in saga with the help of R script or Python script

I am using Ubuntu 12.04 and want to do image classification in SAGA. SAGA has numerous classification algorithms which is not present in GRASS and QGIS. I am new to SAGA, but more accustomed to work ...
1
vote
3answers
229 views

Creating a new raster layer based on mean of other raster layers, ignoring NA values in R

I am trying to create a new raster layer that is made up of the mean values from 7 other raster layers. I get results using overlay function mean: mean <- overlay(2000, 2001, 2002, 2003, 2004, ...
0
votes
1answer
78 views

Cross validation in thiessen polygons interpolation

I apply Thiessen Polygons interpolation using the krige command in the gstat R package. Using krige without a variogram model sets automatically krige function to perform IDW, and when nmax parameter ...
1
vote
0answers
108 views

Using R to find attributes of spatial neighbors, especially with big spatial polygon data frames

If it's not too much, I have a specific question that leads to a more general one: I'd love thoughts on both if it's possible. First, the specific: I have an analysis involving census blocks and ...
0
votes
1answer
370 views

in R : get a SpatialPolygonDataFrame from gIntersection{rgeos] with sub-area as attribute?

I am using gIntersection (package rgeos) to intersect a polygon shapefile containing 20 buffers zones, with another polygon shapefile containing "ground occupation mode (GOM)" (an area divided in ...
6
votes
5answers
3k views

Create a ground overlay kml from georeferenced raster

I have a world georeferenced raster (5m resolution, ~4000 x 4000 pixels) that I would like to display in google earth. I am looking for a simple and effective way to generate this kml file. Using ...
6
votes
2answers
821 views

Calculating Shannon's diversity using moving window in R

I have a raster where each pixel is a particular vegetation type. I'm interested in the diversity of vegetation types around each pixel. I'd like to assign a Shannon's diversity index value (see ...
5
votes
2answers
352 views

writeOGR with a spatialpolygon simplified by gSimplify

I'm using gSimplify (rgeos package) to simplify the geometries of a shapefile. The funcion works good, but now I can't write the output in a new shapefile. I tried some ways: writeOGR(simplyshape, ...
0
votes
2answers
156 views

How to produce a finer resolution spatial grid from coarser grid in R?

I have a spatial grid of an image. Now I want to use this grid and make a finer resolution grid out of it. For example an image structure in R is given below: str(c) Formal class ...
0
votes
0answers
28 views

Dynamic polygons grid with specified area based on raster

I'm interested if anyone have idea how to automatically create (maybe in R?) dynamic grid of polygons with specified approx. area (for example around 20000 m2) based raster data or points with values ...
9
votes
3answers
5k views

Reading File Geodatabase using R?

File geodatabase (fgdb) includes numerous file geodatabase tables. As far as I know they exist as dbf files, but are within a Database.gdb. In ArcCatalog, the file pathway resembles ...
3
votes
0answers
113 views

Spatial weight matrix with boundary effects in R?

I need some help to finalize code for a spatial weight matrix that uses a nearest neighbor definition within regions, but does not allow neighbors from across a political border. For example, ...
6
votes
1answer
679 views

Stats on individual grid points nearest neighbours

I have shp of points where each point is the centroid of the individual cells of a 1*1km grid (~ 500 000 points). For each of these points, I have their coordinates and elevation. What I want: for ...
0
votes
1answer
72 views

How to choose a shapefile interactively in R

I am writing a function in R where i want the user to choose a Esri shapefile from its destination folder. Since a shapefile is made of several files how can i select them. For a point feature class i ...
-2
votes
1answer
44 views

I need to create a function in R that processes rasters in esri grid format [duplicate]

I have loads of data (6500 files that I need to process and find yearly winter sums/averages/variance for. the format for my naming system is Syyyymmdd_rp. Each file is in the same file folder. I ...
3
votes
1answer
143 views

Processing large amounts of Rasters in R

I have 6500 processed and clipped rasters that indicate snow levels on a daily basis in the northern hemisphere. I need to create a raster that represents a sum of the snow for the season. The winter ...
1
vote
2answers
145 views

Getting attribute table from WFS data source

I am attempting to get some WFS 2.0 INSPIRE data from the Finnish meteorological institute into a table format of some kind. Is there any software which can easily grab the attribute data for the WFS ...
2
votes
1answer
2k 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: ...
3
votes
1answer
1k views

How to read feature class in file geodatabase using R?

I have a feature contained in a geodatabase that is larger than 2GB as an exported shapefile. I need to run an extract function in R to attribute the polygons with data from a raster file. Exporting ...
0
votes
0answers
82 views

Thin Plate Spline interpolation

I am completely new to spline interpolation, and I want to apply Thin Plate Spline using the fields package in R, and after I have applied Tps then do leave-one-out cross validation. This is how my ...
0
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0answers
99 views

How to reference to user input in SQL string in R?

I am building a R Shiny interface that queries the user input in Postgresql and generate the respective map layer. However, I am unsure of the syntax to include the query in the SQL string. my codes ...
0
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0answers
234 views

How to convert a geojson from Postgresql to geojson format readable in rCharts in R?

I am creating a Rshiny interface on that can take in user input and SELECT the respectively map layer from Postgresql database based on the input. The package I am using to plot the map is rCharts. ...
3
votes
5answers
3k views

Counting road intersections and blocks

I have a shp file that consists of the road system of Mexico City. I would like to count the number of road intersections (crossings) and blocks (which I would define as a segment starting from one ...
1
vote
1answer
83 views

Compare two rasters in R with the cell value from one replacing the cell value from another

I am trying to create a single raster from two rasters. The first raster is made up of all 0 values and the second is made up of the current date value (formatted in days from 001 to 365). The problem ...
0
votes
1answer
41 views

Calculate mean for a each object of SpatialPointsDataFrame

I have a list with several SpatialPointsDataFrame objects, and each object has certain slots. How can I calculate the meann value of a certain slot for every object in the list, and then save that ...
0
votes
1answer
894 views

IDW in R with cross validation

I want to perform IDW interpolation using R, and more specifically, using the idw command from the gstat package. Also, I want to use the optimal number of neighbors (point locations) and distance ...
1
vote
1answer
584 views

Compare two rasters with raster overlay and replace cell value with variable

I want to compare 2 rasters and when there is a change from 2 to 1 create a new raster that replaces the cell where the change has been detected with the change variable. ## Finds Cells that have ...
5
votes
3answers
4k views

Reproduce raster with same extent, and same number of columns and rows?

I have two raster A and B. A and B have the same grid size but different extent. How can I make A have the same number of columns and rows, as well as the spatial extent of B?
4
votes
0answers
73 views

Why does @data@values slot for RasterLayer only contain logical(0) and not the actual values?

Trying to get to the bottom of why, when I read in a raster of NDVI, the @data@values slot does not contain the actual values until I set them manually. For example: NDVI <- ...
2
votes
1answer
146 views

Trying to limit my shapemap to state boundary lines in R

I have a feeling I'm either trying to do this incorrectly, or I'm just not searching for the correct terms, but I cannot figure out how to do what I want to do. I am trying to plot the ranges of fish ...
5
votes
1answer
2k views

Extracting intersection areas in R

I have two polygons. One contains fields(X,Y,Z) and the other contains soil types (A,B,C,D). I want to know what area of every field contains which type of soil. I tried the following: ...
2
votes
2answers
191 views

Use GRASS through R

I want to use GRASS GIS 7 through R 3.1.3 in kubuntu operational system. Could someone help me connect GRASS with R, and use GRASS commands through R (not the other way round!).
1
vote
2answers
85 views

Aggregate SpatialPoint to form SpatialPolygon

Is it possible to convert SpatialPointDataFrame to SpatialPolygonDataFrame by some kind of generalization or aggregation function in R. how can i form polygons from points of similar color/classified ...
4
votes
1answer
189 views

How to stack rasters for ecological analysis?

The attached image shows two different forest openings. Each opening has the following layers associated with it: Point shapefile 1 = A red X which represent a large "legacy" tree in the gap Point ...
1
vote
1answer
31 views

Workflow for updating raster using polygons of different attributes

I require a specific output but it is proving difficult for me to work out a workflow. I have: 1) polygons of new housing developments (356, non overlapping) 2) a 25m raster of land cover I want ...
0
votes
2answers
279 views

How to get average values per coordinates in ArcMap/R?

I have a point shapefile. It has multiple points at different spatial locations. Within each point there are multiple values that I want to get the average of. In this case the new file would have one ...
2
votes
1answer
45 views

Last SEXTANTE (Processing) update results in missing RScripts examples

I have installed today the new version of the Processing plugin on QGIS 2.8 (on Windows 7 x64) and I cannot anymore find the RScripts example that were available (and functioning) before the udpate. ...
2
votes
1answer
30 views

Mosaic rasterstacks based on minimum of certain layer?

I am trying to mosaic 42 remote sensing rasterstacks (with 250 bands) based on the criterion that in overlapping areas, the pixel should be taken that has the most nadir viewing angle Beside my ...