3102 search results for "GIS"

Quickly read Excel (xlsx) worksheets into R on any platform

June 20, 2013
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I wrote a couple days about about importing Excel files into R. There are lots of ways to do this, but all the ways that use only R have drawbacks (as I outlined in my last post), and all the other ways require installation of programs other than R. I’m not opposed to using programs

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Huge interest in next LondonR user group meeting

June 20, 2013
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The next LondonR meeting takes place on the 16 July and registrations have already exceeded 200. Presentations at the meeting will be made by Rich Pugh of Mango Solutions, Andrie de Vries of Revolution Analytics and Hadley Wickham of RStudio. All places for a  pre-meeting workshop with Hadley Wickham were snapped up within 2 days of announcing the details. More information...

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Spatial Overlays with R – Retrieving Polygon Attributes for a Set of Points

June 19, 2013
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A short tutorial for spatial overlays using R-GIS..library(sp)library(dismo)# spatial dataalt gadm # viewplot(alt)plot(gadm, add=T)# some addressespts # make it spatialcoords spdf_pts # assign CRS/projectionproj4string(spdf_pts) # check datastr(spdf_pts)# plot it on topplot(spdf_pts, cex = 2, col = 2, add = T)# do an intersection (points in polygon)# yielding the polygon's attribute dataover(spdf_pts, gadm)

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Compiling R 3.0.1 with MKL support

June 19, 2013
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Compiling R 3.0.1 with MKL support

Before you begin, be aware that there is others excellent posts about the issue, as: 1. Compiling 64-bit R 2.10.1 with MKL in Linux 2. Speeding up R with Intel’s Math Kernel Library (MKL) 3. Performance benefits of linking R to multithreaded math libraries 4. Using MKL-Linked R in Eclipse But, as recently i faced some problems to The post Compiling...

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An R package for Smith-Wilson yield curves

June 19, 2013
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An R package for Smith-Wilson yield curves

Yield Curve fitting - the Smith-Wilson method Yield Curve fitting - the Smith-Wilson method This article illustrates the R package SmithWilsonYieldCurve, and provides some additional background on yield curve fitting. The method implemented in the package fits a curve to interest rate market...

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Visualising Crime Hotspots in England and Wales using {ggmap}

June 18, 2013
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Visualising Crime Hotspots in England and Wales using {ggmap}

Two weeks ago, I was looking for ways to make pretty maps for my own research project. A quick search led me to some very informative blog posts by Kim Gilbert, David Smith and Max Marchi. Eventually, I Google'd the excellent crime weather map exa...

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Printing R help files in the console or in knitr documents

June 18, 2013
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Yesterday, I was creating a knitr document based on a script, and was looking for a way to include content from an R help file. The script, which was a teaching document, had a help() command for when the author wanted to refer readers to R documentation. I wanted that text in my final document, though. There’s no...

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Quickly read Excel worksheets into R (Windows only…sorry)

June 18, 2013
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I suppose most companies use the Microsoft Office suite of programs, and my office is no exception. It easy to import data from an API or a database into R, but importing data from an Excel workbook is a different story. There are a few R packages for reading Excel files, but I’ve had problems

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Use R to Bulk-Download Digital Elevation Data with 1" Resolution

June 18, 2013
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Here's a little r-script to convenientely download high quality digital elevation data, i.e. for the Alps, from HERE:require(XML)dir.create("D:/GIS_DataBase/DEM/")setwd("D:/GIS_DataBase/DEM/")doc urls names for (i in 1:length(urls)) download.file(urls, names) # unzip all files in dir and delete them afterwardssapply(list.files(pattern = "*.zip"), unzip)unlink(list.files(pattern = "*.zip"))p.s.: Also check raster::getData which pulls SRTM data at 90m resolution for a location / region!

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Annotating select points on an X-Y plot using ggplot2

June 16, 2013
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Annotating select points on an X-Y plot using ggplot2

or, Is the Seattle Mariners outfield a disaster?The BackstoryEarlier this week (2013-06-10), a blog post by Dave Cameron appeared at USS Mariner under the title “Maybe It's Time For Dustin Ackley To Play Some Outfield”. In the first paragraph, Cameron describes to the Seattle Mariners outfield this season as “a complete disaster” and Raul Ibanez as...

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