The Mandelbrot Set is perhaps the most famous fractal of all time. It's simple in its definition: iterate the complex equation zn+1 = zn2 + c (starting with z0 = 0) for various values of c, and if doesn't go to infinity then c is part of the Mandelbrot Set. The result, however, is ... [Read more...]

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Time for another dump of the entire package. Get the zip file 5.1 in the box to the right. ( shortly). unzip and run the following files if you havent already: 1. downloadall.R 2. setup.R If you are running for the first time, You’ll note I added diagnostics. Sometimes the files ... [Read more...]

Since I have resumed my R class, I will restart my resolution of Le Monde mathematical puzzles…as they make good exercises for the class. The puzzle this week is not that exciting: Find the four non-zero different digits a,b,c,d such that abcd is equal to the ... [Read more...]

I finally got the new version of Twitter yesterday, and it looks great. And that's no accident: according to the designer, the layout of the new Twitter interface is based on the Golden Spiral: You can describe the Golden Spiral by laying consecutive squares in a spiral fashion, each square ... [Read more...]

As I am working on my dissertation and piecing together a mess of notes, code and output, I am wondering to myself “how long is this thing supposed to be?” I am definitely not into this to win the prize for longest dissertation. I just want to say my piece, ... [Read more...]

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Our book is finally coming out: You can buy it on Amazon.com, Amazon.de, or Springer.com. [Read more...]

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I am often asked how to fit an ARIMA or ETS model with data having a long seasonal period such as 365 for daily data or 48 for half-hourly data. Generally, seasonal versions of ARIMA and ETS models are designed for shorter periods such as 12 for monthly data or 4 for quarterly data. ... [Read more...]

For the third year running, the Google Summer of Code program has sponsored a number of students working with R, and has again resulted in several new contributions expanding R in various fields. Dirk Eddelbuettel, who coordinated the R-related projects for GSoC in 2010, summarized the results, with details about the ... [Read more...]

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One of my readers asked two weeks ago how to control two graphics windows with the slider in gWidgets. Here is a simple example: if (!require("gWidgetsRGtk2")) install.packages("gWidgetsRGtk2") library(gWidgetsRGtk2) options(guiToolkit = "RGtk2") graphics.off() x11() x11() dev.set() gslider(from = 1, to = 100, value = 10,     container = gwindow("Two Plotting Windows"), ... [Read more...]

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For new users, starting R for the first time can be a little daunting. Luckily, Patrick Burns of Burns Statistics has put together a handy tutorial to help the first-time R user get beyond "blank screen syndrome": So you have successfully started R on your machine. Here's where the trouble ... [Read more...]

Stephen Stigler has written a paper in the Journal of the Royal Statistical Society Series A on Francis Galton’s analysis of (his cousin) Charles Darwin’ Origin of Species, leading to nothing less than Bayesian analysis and accept-reject algorithms! “On September 10th, 1885, Francis Galton ushered in a new era of ... [Read more...]

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I wanted to get R talking to CouchDB. CouchDB is a NoSQL database that stores JSON documents and exposes a ReSTful API over HTTP. So, I needed to issue the basic HTTP requests: GET, POST, PUT, and DELETE from within R. Specifically, to get started, I... [Read more...]