Blog Archives

Accessing, cleaning and plotting NOAA Temperature Data

December 11, 2014
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Accessing, cleaning and plotting NOAA Temperature Data

In my previous post I said that my students are using data from NOAA for their research.NOAA in fact provides daily averages of several environmental parameters for thousands of weather stations scattered across the globe, completely free. In details, NOAA provides the following data: Mean temperature for the day in degrees Fahrenheit to tenths Mean dew point for the...

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World Point Grid

December 10, 2014
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These days I am following a couple of master projects dealing with renewable energy potentials at the global scale. We wanted to try and compute these potential using only free data and see how far we could go.For wind speed there are plenty of resourc...

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R Object-oriented Programming – Book Review

November 28, 2014
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R Object-oriented Programming – Book Review

(This article was first published on R Video tutorial for Spatial Statistics, and kindly contributed to R-bloggers) I have been asked to review the book “R Object-oriented Programming” by Kelly Black, edited by Packt publishing (£14.45 for the E-Book, £27.99 for Print+E-Book).The scope of the book is “to provide a resource for programming using the R language” and therefore...

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Changing the Light Azimuth in Shaded Relief Representation by Clustering Aspect

September 24, 2014
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Some time ago I published an article on "The Cartographic Journal" regarding a method to automatically change the light azimuth in shaded relief representations.This method was based on clustering the aspect derivative of the DTM. The method was develo...

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Transform point shapefile to SpatStat object

August 19, 2014
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Today I wanted to do some point pattern analysis in R using the fantastic package spatstat.The problem was that I only had a point shapefile, so I googled a way to transform a shapefile into a ppp object (which is the point pattern object used by spats...

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Extract Coordinates and Other Data from KML in R

June 11, 2014
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KML files are used to visualize geographical data in Google Earth. These files are written in XML and allow to visualize places and to attach additional data in HTML format.In these days I am working with the MIDAS database of wind measuring stations a...

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Merge .ASC grids with R

April 2, 2014
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Merge .ASC grids with R

A couple of years ago I found online a script to merge several .asc grids into a single file in R.I do not remember where I found it but if you have the same problem, the script is the following: setwd("c:/temp") library(rgdal) library(raster) # ...

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Plotting an Odd number of plots in single image

March 3, 2014
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Plotting an Odd number of plots in single image

Sometimes I have the need to reduce the number of images for a presentation or an article. A good way of doing it is putting multiple plot on the same tif or jpg file.R has multiple functions to achieve this objective and a nice tutorial for this topic...

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Displaying spatial sensor data from Arduino with R on Google Maps

February 26, 2014
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Displaying spatial sensor data from Arduino with R on Google Maps

For Christmas I decided to treat myself with an Arduino starter kit. I started doing some basic experiments and I quickly found out numerous website that sell every sort of sensor: from temperature and humidity, to air quality. Long story short, I bou...

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Interfacing R and Google maps

July 30, 2013
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Interfacing R and Google maps

Introduction I couple of weeks ago I had an idea for a website where people can collaborate to create the first real Audio Atlas, using the power of the Google Maps API. The problem was that I do some programming in R but I did know very few things about HTML and javascript. However, I knew that having...

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