I wrote this code for a project that didn’t work out but I thought I’d share. It takes the dendrogram produced by hclust in R and converts it into json to be used in a D3 force directed graph (slicing the dendrogram near the top to create a ... [Read more...]

I wanted a way of understanding how a clustering solution will change as more data points are added to the dataset on which it is built. To explain this a bit more, let's say you've built a segmentation on customers, or products, or tweets (something t... [Read more...]

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Damage Functions (DFs) translate physical damage to property, resulting from natural disasters, to financial damage. FEMA in USA developed several thousand DFs and these serve as a benchmark in natural catastrophe modeling, both in academia and industry. However, these DFs and their documentation are buried within FEMA's HAZUS software and ... [Read more...]

This is going to be a busy start of summer for me and Rcpp11. I will start by a talk at the 3rd rencontres R in Montpellier on June 26th. Then, over to Bressanone in the italian alps for DSC2014 where I'll give another talk on the next day (June 27... [Read more...]

I currently am reading a bit about using Rcpp and its potential for speeding up R. I found one unexpected example in the lecture from Hadley Wickham: require(Rcpp) signR 0) { 1 } else … Weiterlesen → [Read more...]

Working with a business audience, I am frequently called upon to send analytic results to clients in the form of Excel Workbooks. The xlsx package facilitates exporting tables and datasets Excel, but I wanted a very simple function that would let me … Continue reading → [Read more...]

This is a guest post generously provided by Joe Mihaljevic. A common goal of community ecology is to understand how and why species composition shifts across space. Common techniques to determine which environmental covariates might lead to such shifts typically rely on ordination of community data to reduce the amount ... [Read more...]

by Joseph Rickert For the past year or so we have been plotting the location of R user groups around the world using code (Download RUGS) adapted from a solution that Sandy Muspratt originally posted on Stack Overflow. In last week’s post, we made a modest improvement to our ... [Read more...]

Following up on this post, I have just commited some code that makes the using namespace Rcpp11 ; automatic, I was just tired of typing it. So now, you can just do : #include If however, for some weird reason (some people love litter... [Read more...]

This winter, in my ACT8595 course, I asked my students (that was some homework) to prove that it was possible to derive the conditional distribution when we have a Student-t random vector (and to get the analytical expression of the later). But before, let us recall a standard result about ... [Read more...]

I have seen a few questions floating around the interwebs recently from people starting up in morphometrics and wondering what is the best software to use. I am inspired by my fellow 3D expert Dr. Peter Falkingham's blog post on free sof... [Read more...]

To play in a World Cup national soccer team, a player must be a citizen of that country. But most World Cup players don't regularly play in the nation of their World Cup team. Some hold dual citizenship; others simply play for a league team in a foreign country where ... [Read more...]

R for Software Developers and Data Analysts Saturday June 28, 2014 9:00am-4:00pm Microsoft NERD, Cambridge, MA I’ll be presenting a one day professional development workshop on R programming for software developers and data scientists, sponsored by the Greater Boston Chapter of … Continue reading → [Read more...]

I've been playing with parallelising Rcpp11 implementation of sugar. For example, we have a NumericVector variable x and we want to compute e.g. sqrt(exp(x)) + 2.0. With sugar, we can do: NumericVector y = sqrt(exp(x)) + 2.0 ; and this does not... [Read more...]

I had a very weird issue when I tried to compile (install) certain R packages like "wordcloud", "RSNNS" or "GOSemSim" (a Bioconductor package). The installation always ended with a compiling error at the end.At first, I tried to solve the problem by fi... [Read more...]

Ray DiGiacomo, President of The Orange County R User Group (OC-RUG) in Southern California, contacted us to spread the word about the free webinar they will host on the new “RoughSets” package. RoughSets package This free webinar will provide an introduction to the “RoughSets” package, which provides comprehensive implementations of ... [Read more...]

I’ve been mentioning here that I’ll be discussing a new package, Rth, developed by me and Drew Schmidt, the latter of pbdR fame.  It’s now ready for use!  In this post, I’ll explain what goals Rth has, and how to use it. Platform Flexibility The key ... [Read more...]

Are you a good R citizen and preallocates your matrices? If you are allocating a numeric matrix in one of the following two ways, then you are doing it the wrong way!x [Read more...]

Chaos is the score upon which reality is written (Henry Miller) Nonlinear dynamical systems are an enormous seam of amazing images. The Ikeda Map is an example of strange attractor which represents the movement of particles under the rules of certain differential equations. I have drawn the trajectories followed by ... [Read more...]