Statistical computing language and software environment.

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3
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1answer
208 views

Difference between gdal versions in reading raster on two machines?

I am using raster data from Afripop.org and using the R package raster (raster_2.0-41) to do all my computation. Everything has been working out just fine until I tried sending some jobs to a remote ...
6
votes
1answer
202 views

weighted mean across rasters in R

I have 2 rasters. One raster (bio1) contains temperature information across a continent. The other (sp) contains, for each cell, a probability of occurrence for a species. I would like to calculate ...
5
votes
2answers
1k views

How to extract values from a raster according to Lat and long of the values?

having 12 files with 12 hdrs for one year: these files are raster (projected WGS84,lat long):https://echange-fichiers.inra.fr/get?k=rLSyoavrnifGyH5XrlO samples = 1440 lines ...
5
votes
2answers
2k views

How do I read a 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 ...
5
votes
2answers
1k views

How to implement bivariate Ripley's K function in ArcGIS 10?

The attached image shows a forest gap with red pine represented as circles and white pine represented as crosses. I am interested in determining if there is a positive or negative association between ...
7
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2answers
1k views

Convert several SpatialPointsDataFrames to raster

There are 100 SpatialPointsDataFrames in my Workspace. I loaded them on this way: filenames <- list.files(path="", pattern="XYhectareTravelTimes_ez+.*shp") for(i in ...
0
votes
2answers
93 views

Reversing a “combine” function on a raster

I have a raster that I think was "combined" using an arcmap function. I am wondering if there is a way to extract just one raster layer from the combined dataset in order to use it separately, either ...
4
votes
1answer
235 views

Use csv file as raster file and stitch them together

I'm having an issue trying to stitch together 100 32bit Tiff files (coming from thermal imagery video and extracted as 32bit Tiff). I used Hugin to mosaic the pictures extracted from the video which ...
4
votes
1answer
752 views

Self organizing maps and spatially Constrained Clustering in R

There are a few algorithms to perform spatial clustering in R but most of them focus on point pattern analysis (for example here). I would like to perform spatial constrained clustering for polygon ...
4
votes
1answer
1k views

How to re-project ease( Equal Area Scalable Earth) grid with a ~25 km cylindrical projection to WGS84 0.25 degree? [duplicate]

I have nc (NetCDF) files for global soil moisture. From the metadata, the projection is cylindrical and the resolution is 25 km (it is based on authalic sphere based on International 1924 ...
2
votes
1answer
494 views

Inverse distance weighted interpolation for categorical and/or binary datasets

I want to perform an Inverse distance weighted (IDW) interpolation to a series of points. However my data set can be categorical or binary and just like the IDW I want to interpolate the new values ...
5
votes
2answers
557 views

Spatial Analysis with Factors/Classifications

When doing analysis on spatial data with associated information that is numeric, it is possible to use techniques such as Kriging or Interpolation or Cluster Analysis to find out interesting ...
7
votes
2answers
485 views

How to create a solar intensity map for a garden plot?

I'm interested in creating a raster surface that depicts the average solar intensity per unit area for a small garden plot. I imagine the inputs into the model would be the following: Plot ...
1
vote
0answers
546 views

How to clip the contour map with the polygon using R software?

Hi I am wondering how can I create the contour lines from the discrete x, y and z dataset and then add the shapefile to cut the contour lines by polygon. I want to clip the contour map by the shape ...
1
vote
1answer
121 views

Set certain amount of pixels to 1 inside of a polygon (GRASS)

I have a rather coarse vector map with polygons and want to calculate a (sufficiently) finer raster map defined by spatial extension and resolution. Every polygon of the vector map has a value ...
2
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0answers
42 views

Spatial indexing of a point pattern in R [duplicate]

I have a point pattern and a tessellation (grid) in R. Is there a way to spatially index each of my points? In other words, my tessellation grid has n quadrats, I would like to know for each of my ...
1
vote
1answer
155 views

Interpolated map using pca axes

I have done between group pca in R. I want to make an interpolated map using the eigen values of the first three pc axes. I want to produce a map using each of the three pc axes and finally combine ...
4
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0answers
849 views

How to Export a Shapefile as KML Using R

All, I have exported an ESRI shapefile (polygon) to KML using R, but the resulting layer shows only the outer extent of the polygon. How can I fill in the area with a color? Any help is greatly ...
4
votes
1answer
153 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 ...
3
votes
1answer
3k views

Converting geographic coordinate system in R

I have points in geographic coordinate system and I wanted to convert them to swiss grid (CH1903+). Sample data: id lon lat 2 7.173500 45.86880 3 7.172540 45.86887 4 7.171636 ...
4
votes
1answer
233 views

How to create cohesive Spatial Pixels from Spatial Points Dataset

I have a Spatial Point DF spo (covering an irregular shaped area of interest). The data are not on a regular grid due to crs transformation. My goal is a raster with predefined resolution and extent ...
6
votes
1answer
656 views

How to convert an Erdas training set to .csv?

I am working with Erdas Imagine's Signature Editor to perform maximum likelihood classification. I need to use the same training set created in Erdas for other classification using R. Is there a way ...
1
vote
1answer
640 views

Intersection between two SpatialPolygonsDataFrame using gIntersection function in R

I want to select a subset of my map (a SpatialPolygonsDataFrame) to create a new vector map = part of the initial map included inside a given polygon (eventually, inside several polygons). I have a ...
2
votes
1answer
1k views

Convert a SpatialPolygonsDataFrame to raster using rasterize function

I'm trying to convert my map (a SpatialPolygonsDataFrame) into a raster, using rasterize function, here is a bug that I don't understand... > class(parcel) # this is my map [1] ...
2
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3answers
3k views

How to produce spatial grid from raster?

I need a Spatial Grid as a master grid for diverse thematic maps. How do I produce a Spatial Grid from a raster discarding all NA pixels?
12
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5answers
4k views

Get Raster Values from a Polygon Overlay in Opensource GIS Solutions

I have two layers. A polygon-shape-layer with many tiles and a raster-layer containing CORINE 2006 land cover with many categories in a colourmap. I want to obtain for each polygon in the shapelayer a ...
3
votes
2answers
490 views

How to transform coordinates to location in x-y grid in R?

I have a polygon with a 40m diameter and several points that lay inside it. Now I want to reformat the point locations (projected in DHDN/GK-3, but could vary) to x-y coordinates ranging from zero to ...
10
votes
2answers
2k views

Proper way to rbind SpatialPolygonsDataFrames with identical polygon IDs?

What's the proper R idiom for rbinding SPDFs together when the IDs overlap? Note that here (as is often the case) the IDs are basically meaningless so it's pretty annoying that I can't just make ...
3
votes
0answers
279 views

How do I access layer attributes from within QGIS' manageR plugin?

This is probably a fairly basic question, but searches for manageR come up with a lot of noise, and there's no manageR tag. What I'd like to do is load the attributes from a particular field of a ...
2
votes
1answer
329 views

How to analyze temporal point data in R?

I have XY coordinate data of water depth (n = 30) where each coordinate has water depth attribute data for multiple dates from 2000 to 2007. I have imported the data in r for statistical analysis. I ...
3
votes
2answers
171 views

Where can I get public transportation route information for USA?

I'm trying to find a list of public transit route information, mainly location of bus and train stops for the US. I've looked around at some of the Google products and openstreetmap but can't find ...
1
vote
1answer
349 views

Function that applies another function to nearest neighbors of a specified location?

I'm sure this is quite basic, but I just couldn't find anything appropriate: I am looking for a function that applies another function to variables of a SpatialPointsDataFrame, but only for locations ...
14
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3answers
563 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. ...
5
votes
2answers
789 views

rpy2 installation on Mac OSX. A still unresolved problem on StackExchange and rpy-list [closed]

following lgautier's advice on rpy2 installation on Mac OSX, I posted my request on rpy-list and got in touch with Yair Benita who said he could only install rpy2 through his default Mac OS X python ...
9
votes
2answers
2k 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 ...
5
votes
1answer
437 views

Stats on individual grid points nearest neighbours

First, thank you for this extremely useful and easy-to-access forum! 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 ...
2
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2answers
1k views

How to create a map with states by attribute value?

I'm using Qgis, but I am quite familiar with R and python. So I could use any of these. I want a map of mexico but want to color the stats according to a certain variable. It goes from 0 to 100. So ...
4
votes
3answers
736 views

How to create an intensive map of Russia using QGIS or any other software?

I am trying to create an intensive (heat) map of Russia. I have an excel sheet of 36 Russian regions and their corresponding values. I know that there were similar questions: How to create a map ...
4
votes
1answer
866 views

book/tutorial on using rpy2 in python for kriging?

I am proficient in Python, but have no knowledge of R. Can you suggest a good tutorial in using rpy2 or any other R library to perform Block/Cokriging "Kriging"
3
votes
1answer
430 views

How to reproject a raster to Winkel Tripel projection?

I'm trying to project a raster map (in ASCII grid format) from longlat to the Winkel Tripel projection. But I'm running into errors, for instance gdalwarp won't accept the proj-string. $ gdalwarp ...
1
vote
2answers
774 views

Rename a SpatialPolygon class object in R

I am completely new to GIS but am quite familar with R. I was able to dissolve some zip codes into a larger sales territory. For reference, my previous question is located here. However, because ...
1
vote
3answers
598 views

Merge Zip Codes to Create new sales Markets

Let me preface this question by saying I am very novice with respect to GIS. With this in mind, I am looking to merge zip codes into sales territories. Instead of plotting data by zip code, I want to ...
8
votes
1answer
1k views

How can I use fortify() to create a filtered R data frame from a shape file?

I am in the process of building a ggplot choropleth map of population in administrative areas in Wales. I have downloaded the Boundary-Line data from the Ordnance Survey and extracted what seems to be ...
7
votes
1answer
7k views

How do I change the polygon fill color and border color for SpatialPolygons objects?

I have SpatialPolygons or SpatialPolygonsDataFrames which I'd like to plot. How do I change the color using the three plotting systems in R (base graphics, lattice graphics, and ggplot2)? Example ...
2
votes
2answers
488 views

How to single out country data from a world data map?

Say that i have two "data sources"; A global map of average wind speeds, A shape file (or similar information) of all country borders in the world. How do i combine these two sources and extract ...
4
votes
2answers
502 views

R- alphahull - duplicate points error help

I came across R function -alphahull- and believe it is the best option to turn gps points into a polygon (3 or 4 days worth of gps points across residence/neighborhood for each of 300 subjects). ...
4
votes
1answer
529 views

Iterate features on SpatialPolygonsDataFrame in R

I have a SpatialPolygonsDataFrame object. Is there way to use apply on this object rather than using a for loop to iterate features in this object?
5
votes
3answers
345 views

Create Zonal Grid in R

Suppose I have a n*n raster, and I want to create k square blocks (k can be divided exactly by n*n ) for zonal analysis: for example, when n = 4 and k = 4 a 4*4 raster is create with value 1 1 2 2 ...
2
votes
2answers
2k views

[R]Function to calculate mean for missing or NA values in a dataframe

I am trying to develop a function that will calculate a mean lat/long for my missing or zeros location (lat/long) data in my dataset. I have locations for many SETS within the same TRIP, which tends ...
1
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0answers
822 views

Raster grid for zonal statistics in R

I have two raster layer, the first one r is my zonal mask as a raster grid, and I created as: ext <-extent(Yraster) r <- raster(nrows=32,ncols=32,ext) r[] <-(1:ncell(r)) and project it ...