Statistical computing language and software environment.

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-3
votes
1answer
26 views

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

the format is tiff I have read a tiff image and plot it how to locate pixels and bands of this image now
1
vote
1answer
20 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
votes
0answers
18 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 ...
1
vote
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 ...
0
votes
2answers
36 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 ...
0
votes
0answers
41 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); ...
0
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0answers
16 views

Hausdorff distance is too big for similar polylines [on hold]

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() ...
1
vote
1answer
35 views
+100

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

I would like to perform a spatial overlay to identify the polygon within which my points fall. However I first want to buffer and dissolve the polygons, such that points falling anywhere within merged ...
0
votes
3answers
26 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, ...
1
vote
2answers
32 views

Equivalent to Sieve tool in R {raster}?

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[] <- ...
2
votes
0answers
19 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 ...
6
votes
3answers
123 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 ...
1
vote
2answers
21 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 ...
0
votes
2answers
27 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 ...
1
vote
1answer
25 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 ...
1
vote
1answer
43 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
vote
0answers
10 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 ...
3
votes
1answer
51 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 ...
0
votes
0answers
11 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 ...
2
votes
0answers
43 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 ...
2
votes
0answers
33 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
votes
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 ...
2
votes
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 ...
0
votes
0answers
16 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 ...
0
votes
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
votes
1answer
32 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) { ...
0
votes
1answer
24 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 ...
2
votes
2answers
42 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, ...
0
votes
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 ...
3
votes
0answers
21 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 ...
1
vote
0answers
44 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, ...
1
vote
0answers
24 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 ...
0
votes
0answers
24 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 : ...
1
vote
1answer
22 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", ...
0
votes
1answer
107 views

Unable to run R in QGIS 2.6 - rgdal unavailable for R 3.1

I'm attempting to use R within QGIS2.6 on OSX Mavericks but cannot get R to run because rgdal is not available as binary for R3.1.2 (see QGIS log output from R execution console below). I have ...
0
votes
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
votes
2answers
108 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 ...
2
votes
2answers
46 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 ...
3
votes
1answer
42 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 ...
1
vote
2answers
53 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 ...
1
vote
0answers
49 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 ...
1
vote
1answer
27 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 ...
2
votes
2answers
42 views

combine rasters into single raster with multiple field values in R

I have several raster brick objects that I would like to combine into one raster with multiple field values for each cell, but I am not sure how to do this in R. For example, let's say I have two ...
7
votes
3answers
193 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 ...
2
votes
0answers
30 views

kriging of compositional data (grain size)

I have posted this already in the GEONet Forum but without any suggestions, now I am hoping for some feedback here: I have a problem concerning interpolation of compositional data of grain sizes. I ...
0
votes
0answers
89 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 <- ...
2
votes
0answers
69 views

Raster to polygon using R [closed]

I am trying to convert a raster object to a polygon object using R but I am running into some problems using my Windows 7 machine. I originally tried to use rasterToPolygons (package: raster) but it ...
2
votes
0answers
42 views

How to split a polygon into quadrants in R/Qgis?

I am solving the same problem as How to split a polygon into quadrants?, except that I am looking for a solution in R or QGis. So I have a polygon layer shapefile, which is unfortunatelly not exactly ...
1
vote
0answers
26 views

Unexpected Moran's I value in R using a chessboard example

I'm running into unexpected values for Moran's I when using the Moran.I function in the R library "ape". My understanding is that a chessboard is an example of perfect negative spatial ...