Rule number one in regression testing is to not depend on volatile data. Which I seem to have violated in file t/02simple.t in the Perl package Finance::YahooQuote. Which lead the automated Perl test scripts to remind me for a few days now that the f... [Read more...]

For those of you used to reading about international relations, I apologize for the following brief foray into American politics. It appears that the American Enterprise Institute and David Frum have decided to (abruptly) part ways. Before David left, however, he and his team of interns provided some interesting statistical ... [Read more...]

Not easy to produce cool looking graphs in R, but it can be done. The results of some messing around are above. Here is the code I used: [Read more...]

The results of the 2010 Future of Open Source survey were presented at last week's Open Source Business Conference in San Francisco, and here are they are in slide format: While I was at the presentation I captured a few additional tidbits from the presentation that weren't in the slides. The ... [Read more...]

Inspired from a mail that came along the previous random generation post the following question rised : How to draw random variates from the Von Mises distribution? First of all let’s check the pdf of the probability rule, it is , for . Ok, I admit that Bessels functions can be a ... [Read more...]

A lot of us know about Sweave and Latex and they work very well in creating elegant dynamic reports from R computation. However, sometimes we would like to also produce a word processing document for a colleague or a html version of the same report. Now there are tools for ... [Read more...]

I'm really a heavy user of R and was so much before starting to do any agent based models. So the first thing I was looking in any software package for ABM was some automated link to R (much like spgrass6 for GRASS and R for GIS).  I thought  Repast ... [Read more...]

Matlab and R are two popular languages for data analysis and visualization. The similarity between the two languages is high. Both are interpreted languages that run in a shell-like environment (while also allowing to run scripts or functions written off-line). Both tend to be slow if your code contains many ... [Read more...]

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OK, let's say you want to create a plot and you need an easy way to specify where along the scale your tick marks and labels land, as opposed to having R just decide itself. An easy way to do that is to create a vector and assign the axis ... [Read more...]

mber Watkins gave me a suggestion on the animation for the ratio estimation, and I think this is a good topic for my animation package. I’ve finished writing the initial version of the function sample.ratio() for this package, which will appear in the version 1.1-2 a couple of ... [Read more...]

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Steve Miller at the InformationManagement blog has been looking at predictive analytics tools for business intelligence applications, and naturally turns to the statistical modeling and prediction capabilities of R. Says Steve: The R Project for Statistical Computing continues to dazzle in the open source world, with exciting new leadership at ... [Read more...]

I have put a new version of the RXQuery package which interfaces to the Zorba XQuery engine. This makes the package compatible with the 1.0.0 release of Zorba for external functions. The package allows one to use XQuery from within R and to use R fu... [Read more...]

A week or so ago I had my first experience using someone else’s cluster on Amazon EC2. EC2 is the Amazon Elastic Compute Cloud. Users set up a virtual computing platform that runs on Amazon’s servers “in the cloud.” Amazon EC2 is not just another cluster. EC2 allows ... [Read more...]

otivated by the excellent R package pgfSweave, I begin to notice the font families in my graphs when writing Sweave documents. The default font family for PDF graphs is Helvetica, which is, in most cases (I think), inconsistent with the LaTeX font styles. Some common font families are listed in ?... [Read more...]

The latest release of oro.nifti (0.1.4) has been released on CRAN.  New features include:Added text capability in the (unused) fourth pane in orthographic()A vignette is now included (taken from dcemriS4) [Read more...]

The latest version of oro.dicom (0.2.5) has been released on CRAN.  New features include:Added "mosaic" capability when creating 3D arrays from DICOMdicomTable() now accepts single DICOM fileBetter handling of SequenceItem tags when reading in DIC... [Read more...]

This is the announcement as posted in the mailing list : This is to announce that we plan to release R version 2.11.0 on Thursday, April 22, 2010. Those directly involved should review the generic schedule at http://developer.r-project.org/release-checklist.html The source tarballs will be made available daily (barring build troubles) ... [Read more...]

Over a month ago, David Smith published a call for people to participate in the “Future of Open Source” Survey. 550 people (and me) took the survey, and today I got an e-mail with the news that the 2010 survey results are analysed and where published in the “Future.Of.Open.Source ... [Read more...]