Occasionally, I'll need to pick out names (first name, last name) from text. These days, the text I'm working with is usually tweets. Any how, I didn't see any solution out there (that worked for me) when I developed this, so hopefully it can be a star... [Read more...]

A month ago, I attended a friend’s wedding as a photographer (I am not good at shooting, just have a not so bad camera). I took more than 1000 pictures in high quality format. Later, I relized to share them with the guests attended wedding is a challenge: I need ... [Read more...]

When we created a Shiny-app, deployed it on a server and open it to public, we must have interesting of who visited our app, and if possible, where they from and what they have done. To achieve this, we need a user behavior tracking feature if we are not using ... [Read more...]

R-bloggers is offering an “R jobs” post, that will be published once every (“couple of”) months. If you are interested in offering a job to be posted on [Read more...]

Music is the pleasure the human soul experiences from counting without being aware that it is counting (Gottfried Leibniz) I like the concept of sonification: translating data into sounds. There is a huge amount of contents in the Internet about this technique and there are several packages in R to ... [Read more...]

Introduction As was expected, the runderiv() function has been both useful and deficient. Useful because it offers a good replacement for smooth.spline() calculations of derivatives for things like N^2. And deficient because it only calculated derivatives, not values! Both an extension and a renaming were called for. The result ... [Read more...]

[This article was first published on Yet Another Blog in Statistical Computing » S+/R, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. ### size of csv file: 689.4MB (7,009,728 rows * 29 columns) ### system.time(read.csv('../data/2008.csv', header = T)) # user system elapsed # 88.301 2.416 90.716 library(data.table) system.time(fread('../data/2008.csv', header = T, sep = ',')) # user system elapsed # 4.740 0.048 4.785 library(bigmemory) system.time(read.big.matrix('../data/2008.csv', header = T)) # user system elapsed # 59.544 0.764 60.308 library(ff) system.time(read.csv.ffdf(file = '../data/2008.csv', header = T)) # user system elapsed # 60.028 1.280 61.335 library(sqldf) system.time(read.csv.sql('../data/2008.csv')) # user system elapsed # 87.461 3.880 91.447 To leave a comment for the author, please follow the link and comment on their blog: Yet Another Blog in Statistical Computing » S+/R. R-bloggers.com offers daily e-mail updates about R news and tutorials about learning R and many other topics. Click here if you're looking to post or find an R/data-science job. Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. [Read more...]

Late last week, and just before leaving to participate in this crazy thing, I managed to get a new version of RcppSMC onto CRAN. RcppSMC combines the SMCTC template classes for Sequential Monte Carlo and Particle Filters (Johansen, 2009, JSS) with t... [Read more...]

There's no shortage of web sites listing the current medal standings at Sochi, not least the official Winter Olympics Medal Tally. And here's the same tally, rendered with R: Click through to see a real-time version of the chart, created with RStudio's Shiny by Ramnath Vaidyanathan. (By the way, does ... [Read more...]

Today at the Davis R Users’ Group, Bonnie Dixon gave a tutorial on the various ways to handle dates and times in R. Bonnie provided this great script which walks through essential classes, functions, and packages. Here it is piped through knitr::spin. The original R script can be found ... [Read more...]

Having written a lot of R code over the last few years, I've developed a set of constructs for my most common tasks. Like an idiom in a natural language (e.g. "break a leg"), I automatically grasp their meaning without having to think about it. Because they allow me ... [Read more...]

Following the instructions from CRAN, you need to add the R backports in your source list.FIRST PART: ADD R BACKPORTS: First, open a Terminal and open the sources.list file:$ gksudo gedit /etc/apt/sources.listThen, add these lines a... [Read more...]

As a data scientist I have seen variations of principal component analysis and factor analysis so often blindly misapplied and abused that I have come to think of the technique as unprincipled component analysis. PCA is a good technique often used to reduce sensitivity to overfitting. But this stated design ... [Read more...]

Stephen Few designed the Bullet Graph […] [Read more...]

This post uses pro-football (American) boxscore data from 1966 through 2013 and generates few interactive charts using rCharts, ggplot2 and shiny.  It also provided a first time exposure to the power of dplyr. Data for these charts were scraped fr... [Read more...]

By Ben Ogorek Introduction I only recently discovered the fundamental connection between the C and R languages. It was during a Bay Area useR Group meeting, where presenter J.J. Allaire shared two points to motivate his talk on Rcpp. The first explained just how much of modern R really ... [Read more...]

In the core of kriging, Generalized-Least Squares (GLS) and geostatistics lies the multivariate normal (MVN) distribution – a generalization of normal distribution to two or more dimensions, with the option of having non-independent variances (i.e. autocorrelation). In this post I will show: (i) how to use exponential decay and the … ... [Read more...]

Installing MatLab vs Installing R I retweeted this a few days ago: 1. Open MATLAB for first time in a few years after using #rstats. 2. Site license doesn't work right. 3. F*** MATLAB, I'll try to do it in R— Andrew D. Steen (@drdrewsteen) February 6, 2014 And as I have started the process ... [Read more...]

Python has some pretty awesome data-manipulation and graphing capabilities. If you’re a heavy R-user who dabbles in Python like me, you might wonder what the equivalent commands are in Python for dataframe manipulation. Additionally, I was curious to see how … Continue reading → [Read more...]

Our friend Stefan has been participating in MilanoR since the beginning, and was one of the people who started using R intensively after the "Introduction to R" Quantide course. Since he is from Belgrade (Serbia), and takes part in the … Continue reading → [Read more...]