Statistical computing language and software environment.

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1answer
280 views

Spplot labels in R how to change

Can anyone tell me how to change the labels in a legend created by spplot in R? It is a typical vertical ribbon legend automatically generated by spplot. Based on color, it is labelled 1-7 but I ...
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0answers
13 views

Merging two regions of several into one, to get output SpatialPolygonsDataFrame file

I've been using the large SpatialPolygonsDataFrame file with outdated border of regions. I want to correct boundaries, but also hope to get in the end Polygons with Data Frame again. I used the ...
10
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2answers
30 views

How does spatial polygon %over% polygon work to when aggregating values in r?

I'm working on an environmental epidemiology project where I have point exposures (~ 2,000 industrial hog operations - IHOs). These IHOs spray on nearby fields, but the feces water droplets and smell ...
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1answer
138 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. saf class : RasterStack dimensions : 720, 1440, 1036800, 601 (nrow, ncol, ...
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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): samples = 1440 lines = 720 bands = 1 header offset = 0 ...
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1answer
2k 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 . From the metadata, the projection is cylindrical and the resolution is 25 km (it is based on authalic sphere based on International 1924 ellipsoid). I want to re-project ...
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0answers
14 views

Problem during rasterization [on hold]

coastline<-readShapeSpatial(".shp") road<-readShapeSpatial(".shp") railway<-readShapeSpatial("") boik<-gBuffer(railway,width=50,byid=T) bodik<-gBuffer(road,width=50,byid=T) ...
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0answers
47 views

Python vs R for analzing spatial data

I am relatively new to both the python and R programming languages, having a small amount of exposure to both. Which language has the edge when working with spatial data and when would you use R over ...
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0answers
9 views

fit polynomial function on spectral data

I want to fit a polynomial function (max. 3rd order) on each raster cell over all my spectral bands (Landsat 1-7) creating a new raster(stack) representing the coefficients. I got my data (including ...
2
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2answers
117 views

How to make a movie from a ascii grid files?

Lets say I have several ascii grid files for each time step for a particular location. I would like to spit out the image for each of these ascii grid files and legend on the side bar. I also would ...
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0answers
24 views

How to clip or erase a csv file with a non-rectangular shapefile?

I can clip a csv file with a ogr2ogr having 4 extents of a rectangular polygon. Is it possible to clip a csv file with a non rectangular shapefile?
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14 views

R to ArcMap, erroneous change of spatial reference

I have SPOT5 imagery from Northern Sweden / Finland. Data is downloaded from SACCESS service and is provided in Sweref99 TM projection. When opened in ArcMap the data is shown in Sweref99 TM as ...
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1answer
168 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 ...
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1answer
34 views

Function to merge geojson and csv data in R

I have been using merge() to merge my geojson file with csv data in R. My codes are as follows: map@data <- merge(map@data, csvdata, by.x="ID", by.y="ID") However, after exporting the geojson ...
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1answer
137 views

Package getcartr Installation Problems

I want to build a cartogram by following this tutorial. The first thing I did, I spent the R-R-3.1.1 version 3.1.2 then I did the following: library(devtools); ...
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2answers
804 views

Calculate area covered by a particular raster layer within polygons in QGIS

I am trying to extract information on vegetation cover within a set radius of point locations (my sites). I have succeeded in creating a new vector layer of circles with a 5 km radius around my sites. ...
16
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2answers
3k views

Performing Raster Noise Reduction and Edge Smoothing?

I have a raster image like this I want to delete the isolated noise point and smooth the edge (say the white single points, and I want the edges of the entity look smooth). How can I do this in ...
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0answers
22 views

Raster data in R to merge to a time series

I have gridded data files about 2000 ( see sample -each file consist of monthly rainfall and is label pYYYYMM) https://www.dropbox.com/sh/63z166tjxyu12s5/AAAs3Ccn1zdVoBYMj8Y1o303a?dl=0 ...
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0answers
24 views

moving window regression on raster stack in R

I want to perform a moving window regression on every pixel of two raster stacks representing Band3 and Band4 of Landsat data. The result should be two additional stacks, one representing the ...
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1answer
23 views

How can I convert a geojson file to topojson in R?

I have tried the geojsonio package but it does not allow me to convert my geojson to topojson format. I know there are web applications available online to convert from geojson to topojson, but my ...
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3answers
32 views

Unable to read raster into R: 'TIFFReadDirectory:Failed to read directory at offset'

I'm getting a weird error when trying to read a raster into R. >r <- raster('myraster.tif') Error in .local(.Object, ...) : TIFFReadDirectory:Failed to read directory at offset 2606110 ...
3
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1answer
66 views

Strange spatial interpolation results from ordinary kriging

I'm using Ordinary Kriging to interpolate a set of spatial data. I'm working on different sets which represent different days of measurement. I get good results, apart from one specific set. Will post ...
0
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1answer
416 views

Summarize values from a raster brick by latitude bands in R

I would like to sumarize (sum and/or mean) values from layers on a raster brick based on latitude bands (been using raster package). Been looking at the package documentation and didn't find a way to ...
3
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1answer
311 views

Extract pixel value for corresponding gps location in R

I have animal gps data with several locations for each day and regular gaps of several days when no location of the animal was recorded. Additionally, I have satellite data in intervals of 16 days. I ...
2
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1answer
186 views

Extract number of vertices in each polygon in R

Simple question: how to extract the number of vertices in each polygon in R? I've found one way that works, but this is very slow (when x is a SpatialPolygonsDataFrame): y <- fortify(x) n.verts ...
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1answer
29 views

RasterStack extract() for duplicated dates

I have a a Large RasterStack of temperatures and a 10570 points in a Large SpatialPointsDataFrame and I'm using extract() to assign the temperatures to each point in R. ...
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0answers
155 views

Ecoregions shapefiles: subsetting, extracting and summarizing data from raster

I am attempting to subset and project an ecoregions shapefile from : EPA ECOREGIONS my data set is found here: SHAPEFILES and RASTER When I run this code, two major problems occur: 1) I cannot get the ...
1
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1answer
149 views

Determining Pixel-by-pixel Catchments in ArcHydro

I used ArcHYDRO to prepare HydroDEM (5m) without sinks, Flow direction (FDR) raster, flow accumulation raster (FAC). As I understand FAC, value of pixel shows number of pixels that contribute to this ...
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2answers
221 views

projection conversion from mercator to google maps format

Is this spTransform(Finland3, CRS("+proj=longlat +ellps=WGS84 +no_defs+ellps=WGS84 +towgs84=0,0,0 ")) the right way to project a shapefile with this projection coord. ref. : +proj=merc +lon_0=0 ...
1
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1answer
127 views

Find all census tracts N miles from a lat, lon point

Using R, I'd like to find all census tracts within a given distance of a point (lon,lat). i.e. All census tracts within 20 miles of 34.0522, 118.2428 I have used the sp library and over command to ...
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3answers
140 views

How to calculate mean aspect in circular statistics?

Measurements of angles (e.g. compass bearings, aspect) are circular in nature (e.g. 0 and 360 degrees coincide) and therefore cannot be meaningfully described by ordinary arithmetic means. I have a ...
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1answer
29 views

How can I export a GeoJSON file from R?

The write. function allows one to export a JSON file, but it does not seem to work for a GeoJSON file. This is the code i ran: write(map,"Map Layer2.GeoJSON") and this was the error produced: ...
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1answer
552 views

Can't plot polygons with R and ggplot2

I am new to shapefiles so I maybe ask some stupid questions, sorry. I want to plot a map of my region, with colour filled polygons using R. I have downloaded municipal (lines) and province (polygons) ...
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3answers
80 views

Spatial distribution of an invasive specie across a landscape : what analysis?

I'm studying the spatial distribution of an invasive specie introduced in a natural area. This plant, that thrives in sunlight, grows in thickets (patches). The population of my study site (10x10 km) ...
0
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1answer
67 views

Can't import libraries to rsaga

I get this error when I'm trying to import a raster to RSAGA: > rsaga.import.gdal(paste(rast_name, ".tif", sep=""),"RASTER", env= my_env) Module 'GDAL: Import Raster' not found in SAGA library ...
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0answers
32 views

Comparing point pattern distributions using Geostatistics with R?

I have a data set consisting of about 1,500 points of an unknown distribution. About 60 of the points represent special conditions like infekted people. How can I determine if the 1,500 points and ...
0
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0answers
24 views

weight a raster by another for a model ( R/ arcgis/maxent)

I have an idea in mind for my project but I can't figure out how to do it in R and Arcgis. Basically I would like to do a weight a raster by another for my maximum entropy model. -I got a raster ...
6
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3answers
788 views

Spatio-temporal block kriging with R package gstat?

In the documentation of sp I saw that the coords argument of the SpatialPolygons function only accepts 2 columns. Is it not possible to create 3-dimensional polygons? I am doing spatio-temporal ...
2
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1answer
51 views

How do I set up the R Script folder in QGIS 2.8.1 Processing Toolbox (Advanced Interface)?

I am currently lacking the R Script folder in my processing toolbox under the advanced interface tab. I suspect this could be a result of the firewall in my company's wifi. I already have R ...
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0answers
36 views

Convert Eps to geographic distance using DBSCAN

I am using the dbscan cluster (package fpc) in R to find clusters on a set of latitudes/longitudes coordinates. I want to find an eps distance that corresponds to a meaningful geographic distance ...
2
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5answers
2k 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
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1answer
144 views

Clump and eliminate classes in a raster in ArcMap or R

after interpolation of sediment classes, I obtained a raster which looks like the image below (sample of the river). I would like to clump and eliminate areas within the raster that are below a ...
0
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1answer
17 views

TopologyException error during fortify SpatialPolygonsDataFrame

I tried to reproduce a recent question on spatial data visualization using ggplot2 and received the following error message during fortify(world, region = "ISO3"): Error: TopologyException: Input ...
3
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1answer
46 views

Plotting data without geographical coordinates besides the main map in ggplot2

I am trying to plot some data as a bubble chart on the world map using ggplot2 package in R. I am able to proceed as follows. # Load necessay packages library(ggplot2) library(rworldmap) ...
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0answers
36 views

Rasterize and union problem

i've done the union first and then rasterized it. But now i want instead of that, to rasterize each one and then merge it as one. How do i do that? I mean without the union first off. ...
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1answer
37 views

Choosing R package for discrete choice model?

I am at a loss as to which R package and approach to use for my modeling. The background is: I have a transportation survey dataset combined with many other GIS datasets. I am attempting to ...
2
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1answer
29 views

Perform affine transformation on shapefile with OGR, GDAL, or other command line tools?

Transformations with WKT or EPSG code are made easy with ogr2ogr, but are there tools for me to define my own affine transformation to apply to the coordinates of a shapefile? Or, in general, is ...
2
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1answer
78 views

How can I parse modis MOD13Q1 quality layers in R?

I'd like to parse MOD13Q1 VI quality layers in R. My original code must have been incorrect, because it gave lots of "deep ocean" flags in the middle of Brazil. After the changes suggested by ...
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2answers
54 views

How can I loop through a list to create rasters and write them to .tif files?

I received 3 .mat files that each contain several daily maps. I need to take them and get them into ArcMap (10.2 if that matters) as a .tif with spatial information. I have already used the R.matlab ...
0
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1answer
30 views

Add Polygons to SpatialPolygons via loop / iteration using R?

Just out of interest: I'm creating a SpatialPolygon (R with package "sp") with a number of Polygons within. Is there a way to loop this task? I'm doing it manually as follows. The Polygons consist of ...