Statistical computing language and software environment.

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3answers
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Difference between raster subsets as defined by another raster

I wish to determine whether there is a relationship between slope and the Corine land cover class pastures. i.e. whether areas defined as pasture have a different slope to non-pasture areas. I've ...
2
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0answers
23 views

Computing Shannon-Weiner biodiversity index using QGis

I wonder if anybody has some experience in calculating biodiversity index (such as Shannon-Weiner) using QGis. I am also interested for similar experiences using R scripts within QGis. The analysis ...
0
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0answers
19 views

Construction of a square grid from a given centre (lat,lon) and direction of the sides

Let us consider a point (longitude, latitude) on Earth (location). How to construct a square grid around this point (taking this point as the centre of the square or intercept of the two diagonals) ...
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0answers
12 views

Can't run sgolayfilt () on RasterStackTS in R

I'm quite new in R and remote sensing at all. Had followed the following step to filter my MODIS/NDVI data. library(sp) library(raster) library(rgdal) library(rts) library(signal) getwd() ...
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1answer
18 views

Distance to nearest point for every point same SpatialPointsDataFrame in R

I have a SpatialPointsDataFrame that I'm working with in R. I want to add a new vector to the dataframe that contains, for every point, the distance to the nearest other point in the ...
3
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1answer
45 views

Join spatial polygons by code in R

I am in the process of creating a spatial polygon map for the Valencia region in Spain. I asked the question in StackOverflow (http://stackoverflow.com/q/19791210/709777) and could produce the map. ...
2
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1answer
65 views

Change countries boundaries color in a shapefile with R

I am working with R to create a map with a shapefile. I would like to change the color of the countries boundaries but I don't know how to do that. Is it possible to change the color? Here is my ...
2
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2answers
90 views
+100

buffer and union in R without reducing to a multi-polygon

I would like to perform a spatial overlay to identify the polygon within which a set of points fall. However I first want to buffer and dissolve the polygons, such that points falling anywhere within ...
2
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2answers
42 views

Remove clumps of pixels in R

I would like to remove isolated pixels (or clumps of pixels <9) from my raster image. library(raster) # create some raster data r <- raster(ncols=12, nrows=12) set.seed(0) r[] <- ...
0
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1answer
65 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); ...
3
votes
1answer
339 views

Find which grid cells contain a point

I have a dataframe with x,y coordinates. I've sampled 10 x,y coordinates from my dataframe: y <-c(24.637032,21.569813,21.687,19.677183,24.72438,21.433136,24.637032,22.21065,21.443762,25.273882) x ...
0
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1answer
50 views

Finding correlation between point location and raster value

I have what i thought was a very simple problem but i think i may have overthought it.... I have a population density raster and a point feature layer showing the locations of X (about 70 points). ...
2
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1answer
67 views

Incomplete intersection area using gIntersection in R

I have two SpatialPolygonsDataFrame, one of them is the deforested area in the Amazon and the other is the city of Vila Rica, which is in the same region. I would like to calculate the total ...
3
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1answer
25 views

Add a point shapefile layer to a polygon shapefile window in R

I'm new to Spatstat for R and I'm trying to add a point layer to a window I've created from a polygon. I see questions like this have been asked before but I still can't get what I need from the ...
0
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3answers
36 views

Save rasters created by loop operation to different directory?

I have a set of rasters. I crop them all using FOR loop. Then, I want to save new-created rasters in new directory, not in my actual directory. For one raster it is easy: writeRaster(raster1, ...
2
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1answer
453 views

How to perform a true GIS clip of polygons layer using a polygon layer in R?

I would like to do a true GIS Clip in R of soils polygons using a series of single boundary polygons, but I cannot find an R function to properly do it. It should work just like the CLIP function in ...
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1answer
31 views

How to locate pixels and bands of image in R [closed]

the format is tiff I have read a tiff image and plot it how to locate pixels and bands of this image now
1
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1answer
25 views

Querying Postgis data in R using dplyr package

Does anyone have a workflow for querying postgis data in R using the dplyr package? R doesn't like the spatial columns in postgis data so can't read them in like a postgres table. I get the error ...
2
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0answers
23 views

R Spatial: Trouble with disjointed polygon that has self-intersections

I have a shapefile which represents the areas of a city which have higher risks of flooding than others. This is a spatial polygon object however the polygon is disjoint and not connected. I also have ...
0
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2answers
41 views

How to read and write tiff image and locate pixels and bands of images in R

I'm new in R I want to know how to read and write tiff format image in R and how to use R to locate pixels and bands of images My environment is in Windows when I try to read tiff image it shows ...
1
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1answer
31 views

How to build a function that extracts information from a set of polygons at multiple points in R

I am new to R, and trying to build a simple function that calculates an average (mean) of Sum_MVKT extracted from a set of predefined point locations. For this, I have two shapefiles named ...
4
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1answer
2k views

Joining polygons in R

I am wondering how to join spatial polygons using R code? I'm working with census data where certain areas change over time and I wish to join the polygons and the corresponding data and simply ...
0
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0answers
20 views

Hausdorff distance is too big for similar polylines [closed]

I am using Hausdorff distance to compare two polylines as follows: library(rgeos) hdist <- rgeos::gDistance(mySpatialLines[1], mySpatialLines[2], byid=FALSE, hausdorff=TRUE) x11() ...
5
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2answers
2k views

How to make RASTER from irregular point data without interpolation

I was trying to make a raster image from an irregularly spaced point database. The data looks like- > head(s100_ras) x y z 1 267573.9 2633781 213.29545 2 262224.4 2633781 ...
1
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1answer
156 views

Convert point to grid: Numbers of cells differ

In R I am trying to aggregate points data to a grid. The data for the grid (G-Econ) comes as a csv-file. In this file each row represent a grid-cell at 1x1 degree resolution and the given ...
2
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0answers
22 views

How to measure similarity of approximately congruent polylines

My initial question was posted here. The answer of whuber provides a nice solution for the case when polylines are congruent. However, the problem is that my polylines are approximately congruent ...
1
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2answers
25 views

Getting raster values on grid nodes

I have my raster layers of Digital Elevation Model, aspect, slope and curvature for a certain region. In this region I want to apply a grid with a certain spacing in its nodes, and then get the ...
6
votes
3answers
137 views

How to measure similarity of SpatialLines objects

I created two SpatialLines objects in R: . These objects were created this way: library(sp) xy <- cbind(x,y) xy.sp = sp::SpatialPoints(xy) spl1 <- sp::SpatialLines(list(Lines(Line(xy.sp), ...
3
votes
1answer
52 views

Add a single column to multiple SHP

I was looking for a way to add a new column to several shp (simple polygons) at the same time. I don't know much about batch command. This new attribute is also a little bit tricky : I need to ...
0
votes
2answers
29 views

System call gdal function in R on Mac

Hopefully someone can help me figure this issue out. I am trying to system call gdal functions inside of R using the system / system2 functions. Here is an example of the code: > system("gdalinfo ...
2
votes
1answer
31 views

How to write every raster from a list of rasters?

I have created a list of rasters - "norm" and run a several loops. Now I would like to write every created raster from "norm" (containing 1 layer) into one raster, having its specific name. # I can ...
18
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4answers
16k views

How to open a Shapefile in R?

I need to open a shape file from ArcMap in R to use it for further geostatical analysis. I've converted it into ASCII text file, but in R it is recognized as data.frame. Coordinates function doesn't ...
1
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1answer
52 views

r - increase speed of crop, mask, & extract raster by many polygons

I'm extracting the area and percent cover of different land use types from a raster based on several thousand polygon boundaries. I've found that the extract function works much faster if I iterate ...
1
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0answers
14 views

Using the accCost() function in R: questions regarding the transition layer

I am trying to use the accCost() function from the gdistance package in R. I load my cost raster using the raster()function from the raster package. According to the documentation, I need first to ...
0
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0answers
12 views

How to run GAM with raster package?

When I am using the raster package to predict a surface probability map of species distribution using the following functions in R, the following error occurrs: CA132122200=raster("F:/CBG ...
4
votes
1answer
60 views

How to import multiple stacked raster images in R?

I have (I suppose) wery easy and silly question but I can´t really find my answer... I would like to import all multiple mosaic rasters (each mosaic is composed by 7 layers) from indicated folder into ...
2
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0answers
35 views

Calculate Euclidean distance to raster WITHIN multiple polygons

I am using ArcGIS 10.1 on a Windows x64 system. I am working in a study area where I have 360 000 locations of about 50 territorial animals. I have a shapefile containing 125 sometimes overlapping ...
2
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1answer
71 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
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0answers
24 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
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1answer
16 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
575 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
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0answers
25 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
247 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
25 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 ...
1
vote
1answer
102 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 ...
0
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1answer
44 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 ...
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0answers
12 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
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1answer
33 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
87 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
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2answers
44 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, ...