In this post I’ll cover setting up a virtual environment in Python 2.7 in preparation for working out a RESTful app in Flask.
An Introduction to Vim
This post will represent some running notes regarding the use of the Vim editor. Why should you use something as arcane as Vim you ask? Well, sometimes you find yourself on a server or something that doesn’t have any other editors, so you should be know some Vim basics. Plus, it’s fun.
Vim is built on vi, an even more bare-bones editor. At the outset you should know that Vim has two modes, normal or command mode, and edit or insert mode. You add words and stuff in edit mode, and you perform operations like searching, saving, and moving around in normal, or command mode. (I prefer the edit/command terminology.) You can always get into the command mode by hitting ESC.
Creating a Presentation with R
In this post I’ll look at creating a presentation using the R ecosystem. I’ve used beamer before, and I love it, but I haven’t used the knitr R package yet. Incidentally, the creator of knitr, Yihui Xie, does not like beamer. This is fine, I have been wrong about technology before–I recall thinking in college that facebook was for losers and that it would never catch on. Anyway, Yihui’s work is really impressive and I strongly suggest checking it out.
Installing Debian Packages
If you are running a Debian Linux system, like Ubuntu or CrunchBang, you’ll occasionally need to install a .deb file, which is a binary file used to install packages. Usually you can simply run,
sudo dpkg -i ./path/to/file.deb
Modeling in R with the caret Package
Decision Trees in R using the C50 Package
In this post I’ll walk through an example of using the C50 package for decision trees in R. This is an extension of the C4.5 algorithm. We’ll use some totally unhelpful credit data from the UCI Machine Learning Repository that has been sanitized and anonymified beyond all recognition.
tidyr and pandas: Gather and Melt
In this post I’ll look at replicating Hadley Wickham‘s gather() tool from his tidyr package using the pandas melt() function. Why would anyone want to do this? Well, Dr. Wickham’s work is beautiful, and the pandas.melt() function is not as elegant as the tidyr::gather() function. You may read Dr. Wickham’s pre-print paper here.
Updating R from the Command Line
This is a tiny post, but if I lumped it as an aside into a longer post I might never find it again. If you’re trying to keep up with Hadley Wickham you might need to update R from time to time. The installr package is there to help you keep up with the Wickhams. To update R, just follow the following steps:
install.packages("installr");
library(installr);
updateR();
For further infromation, check out this r-statistics post on the topic.
Getting Started with MongoDB and Python
In this post I’ll walk through getting started with MongoDB using the Python PyMongo module. I’ll go through the installation process, and then walk through an example of entering data into a MongoDB through Python. (In a future post I’ll cover querying documents.) For the installation, I’ll assume that you’re running Ubuntu, but there are instructions for all major operating systems on the link that I have provided.
A Quick Note on Using Git
In his post I will summarize what I gathered from the Atlassian Git tutorial that had lots of really great examples and explanations. I’ll assume you’ve already configured your Git installation and account, but aren’t sure where to go from there. I’ll also assume you’re using linux.