Statistical computing language and software environment.

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2
votes
1answer
73 views

Whats the best way to convert this tab data to a raster?

I have some grid data that is stored in a xls file. The rows are lattitude and the columns are longitude values in decimal degrees (see image). What would be a quick and efficient way to convert ...
0
votes
0answers
27 views

Spatial regression lag on dependent and independent variables in R

I have a SpatialPolygonsDataFrame with summarize data about some regions. How can I make a spatial regression with lag both in the independents and dependent variables in R, like this: Where y is ...
2
votes
1answer
24 views

Converting character attribute to numeric attribute

I am following the very simple code found in this question Converting shapefile to raster: Character attributes to create a new numeric variable based on a factor. My proble is that the new numeric ...
4
votes
1answer
605 views

How to split a polygon using R

I have an irregular polygon which is a spatial object. I want to divide it into multiple polygons (say, n=25) with equal height. To show how I want to divide it, I've plotted grids on the ...
0
votes
0answers
46 views

gpclib package in R

I'm trying to do a locoh run on R version 3.1.2. Since the gpclib package is depreciated, I've installed and loaded rgeos (the package gpclib has been replaced with). However, the locoh run can still ...
2
votes
1answer
280 views

How to work with flt & hdr files

I have been working on a vector-based spatial analysis in R using shapefiles. I wish to use some environmental data that is downloadable, however it is only available in raster format (FLT & HDR ...
0
votes
1answer
42 views

For loops + boxplot for raster

I have several Rasterstacks (b1_mask, b2_mask,...) of several layers representing only a determined pixel-intensity range. (So point "A" in some layers is "NA" - in others a "value" of that certain ...
0
votes
1answer
47 views

Extent from Centroids, Projection, and Resolution?

I have a file that defines a raster, although all the metadata was lost. I know the lat/long coordinates of the grid centroids, and that the grid is in a Mercator projection with a 1/12deg equatorial ...
0
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0answers
15 views

KDE looping in GME

I can not get this for loop to run in GME because i is being changed to 1 and , out is not recognized: wd <- "C:\Users\name\Desktop\KDE\2011\"; for (i in 1:15) { ...
0
votes
1answer
42 views

GME: could not open input point data source

I can not get this for loop to run in GME because i is being changed to 1 and , out is not recognized: wd <- "C:\Users\name\Desktop\KDE\2011\"; for (i in 1:15) { ...
1
vote
1answer
90 views

R: distance from one point to many polygons

OK so I have a spatial polygons data frame, and I have a point of interest. I want to add a row to the SPDF that contains the distance from the centroid of each polygon to this given point. How do I ...
2
votes
2answers
51 views

Create lines from polygon borders with polygons attributes

I have a shapefile of polygons that border each other perfectly, each with a numerical attriubte. I'd to create a shapefile of lines, where every line is created from the border between two polygons, ...
3
votes
0answers
28 views

Subset two rasters with different extent and origin (and resolution) only where there are data in both in R

in R, I have two rasters with different extents and origins (and possibly even resolution). How to efficiently take the subset of each of them only where there are data in both of them? Here is a ...
4
votes
0answers
163 views

Performing cluster analysis in R with Point Datasets

I am a R-Beginner, but I want to use it for some spatial statistics. I want to check the relation between the occurrence of ill persons and the existence of water in a area of interest. To give you a ...
1
vote
1answer
83 views

How to infer a relationship between two spatial points using R

I am quite new to the area of spatial statistics, but I'm very interested. For learning and demo purposes, I've created three datsets. Dataset - Persons: This describes individuals at a certain ...
1
vote
1answer
42 views

Export to images subsets of Spatial Points Data Frame

I have a csv file, which I converted it to Spatial Points Data Frame. And I want to split the spatial data and export each map to a jpg file. I did the following: SB <- read.csv("SB_040914.csv", ...
1
vote
0answers
63 views

How to extract percentage of land cover from a raster according to multiple shapefiles?

I have a raster map that represents land cover of a region, and different shapefiles (total 120) in the same region. I want to know the percentage of every land cover for each shapefile. For example, ...
26
votes
6answers
9k views

Tutorials to handle spatial data in R?

Does anyone know some good tutorials to handle spatial data in R? I know that there are some packages like rgdal and maptools but I haven't actually found usefull tutorials to get in touch with the ...
2
votes
2answers
155 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
30 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
111 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
votes
0answers
62 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
vote
0answers
92 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
198 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
84 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
votes
0answers
50 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 : ...
0
votes
0answers
55 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
308 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
91 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
vote
0answers
63 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
186 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
494 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
128 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
765 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
281 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
votes
0answers
117 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
142 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
381 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
17k 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
137 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
61 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
56 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 ...
18
votes
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 ...
1
vote
1answer
739 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
456 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
vote
0answers
60 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
49 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
236 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
198 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
30 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 ...