Statistical computing language and software environment.

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146 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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85 views

Python vs R for analzing spatial data [closed]

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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11 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 ...
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2answers
155 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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38 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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16 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
54 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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2answers
4k 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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45 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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37 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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1answer
111 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 ...
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442 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
320 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
195 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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162 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 ...
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1answer
153 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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1answer
137 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
178 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
43 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
589 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
100 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) ...
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1answer
84 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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29 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 ...
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3answers
810 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
92 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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1answer
27 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
114 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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37 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
48 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
48 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
110 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
63 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 ...
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1answer
41 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 ...
4
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1answer
399 views

R Raster package loop over pixels

I want to perform a trend analysis for each pixel over it's time dimension. Therefore I wrote a loop over each pixel doing the calculation but this is extremely slow. I am sure there must be a faster ...
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2answers
40 views

PostGIS raster write support in R

I want to push/write some generated raster layers to my postgres database directly in R. In theory this could be supported by the rgdal package, but sadly it isn't. In the latest version only copy, ...
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0answers
45 views

Matching (joining) two slightly incompatible polygon shapefiles

I have two shapefiles that represent two slightly different zonings of the same area (municipality zoning and transport zones), about 3000 polygons each. Several smaller municipalities may form a ...
2
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1answer
49 views

Extracting point information from raster in R

I'd like to work with climate data available from here and extract values of certain locations (for which I have lat and lon). This is what I've done so far: library(SDMTools) library(raster) test ...
2
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1answer
102 views

Difference between raster() and readGDAL()?

I am new in working with rasters and after having trouble working with them i'd like to know the difference between those two import functions. for example i did this library(raster) ...
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2answers
71 views

How to read ArcGIS files in R?

I am new to using spatial data in R. So far the tutorials I have seen consist of using maptools, map, ggplot2 and rgdal to open ".shp" files along with ".csv" files to plot the polygons/ points using ...
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0answers
68 views

How to get time-zones from latitude and longitude in raster?

I have a raster with longitudes and latitudes for the US with meteorological data (for about 100k grid points). I would like to get the time zone for each point in order to transform the time to local ...
2
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2answers
172 views

Classifying DEM according to elevation in R?

r<-raster("DEM.tif") How to do the classification based on every ten meters for example and have different colors too?
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0answers
78 views

Error in downloading MODIS image using R script

I am trying to download "MOD13A3" MODIS image using R script (http://r-gis.net/?q=ModisDownload) but each time it's ending in error. How to make it work ? ...
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0answers
44 views

Location allocation optimization using R?

I need to allocated zip codes to offices. Each zip code has certain demand from 0 to 120 clients and each office has certain capacity from 500 to 2500. How do I do this so that: All the zip codes ...
2
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1answer
65 views

Defining projection using readOGR if the shapefile doesn't have it?

I think that by using readOGR to import a shapefile renders worthless to put proj4string to the script since if any coords are available in the shapefile, it will be transported through the readOGR. ...
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1answer
73 views

encoding error between maptools and arcgis

I am having a trouble of encoding at writing shape file by maptools (0.8-34) of R by MacOSX and reading that by ArcMAP 10.2.1 in windows 8.1 through parallels desktop. Using an original shape file, I ...
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1answer
115 views

Reading and plotting shapefiles with a custom function in R?

I have this piece of code that want to turn into a function r<-readShapeSpatial("roads") b<-readShapeSpatial("buildings") lc<-readShapeSpatial("landcover.shp") here is the preparation ...
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1answer
46 views

error of randomforest classification with Landsat data

I want perform randomforest classification on Landsat data. Here is some code I found from a paper. But when I run into the "classification" part, there is an error said "Error in eval(expr, ...
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2answers
34 views

Include non-raster object in overlay function in R

I have two raster objects and I would like to calculate values of the first conditional on values in the second. I am currently using the overlay function, but unfortunately I can't seem to pass non ...