aRrgh: a newcomer’s (angry) guide to R

Tim Smith <arrgh@tim-smith.us>, @biotimylated
with Kevin Ushey <kevinushey@gmail.com>, @kevin_ushey

An apology.

Every once in a while, this document catches the wind.

Since I first wrote it, I have become less convinced of the fairness, importance, and sophistication of many of the criticisms I’ve leveled.

I’ve become quite productive in R. I’ve also spent some time as a maintainer of a popular open-source tool and learned how it feels to be the target of abuse from Internet Randos. (I survived, but it wasn’t motivating.)

I’ve long intended to reconsider my arguments and tone but engaging with my own embarrassing writing was never the most interesting way to spend a weekend.

I’m grateful to the R community for their labors. I use R and benefit from R and I apologize for the lack of empathy I show here. I’m leaving the rest of the document unchanged for the moment in hopes that the technical content is useful to new users but I expect to revise it soon and remove many of the “good parts.”

R is fine. (Do use the tidyverse.)

Introduction

R is a shockingly dreadful language for an exceptionally useful data analysis environment. The more you learn about the R language, the worse it will feel. The development environment suffers from literally decades of accretion of stupid hacks from a community containing, to a first-order approximation, zero software engineers.¹ R makes me want to kick things almost every time I use it.

But there are a lot of great tools that are built in R. ggplot2 is first-in-class and Bioconductor packages are often essential. Sometimes there’s aught to do but grin and bear (though never without a side of piss and moan).

The documentation is inanely bad. I can’t explain it. aRrgh is my attempt to explain the language to myself. aRrgh exists as a living document and will continue to grow – it is not complete, but it got to a point where it seemed like it was probably useful so I decided to toss it on the web. It should be correct and it’s a bug if it isn’t. Please email me or file issues on Github.

The goal of the document is to describe R’s data types and structures while offering enough help with the syntax to get a programmer coming from another, saner language into a more comfortable place.

Table of contents

• Basic syntax: crash course and gotchas; finding help
• Atomic vectors: R’s simplest data types; logic values; vectorizing; arrays
• Factors: A useful and misunderstood data type. Where they come from, how to handle them
• Data frames: R’s structure for tabular data. How to create them, access semantics

To come?:

• Indexing
• Lists
• Namespaces
• Beyond Base R, Or: How I Learned To Stop Worrying and Love the Hadleyverse

Colophon

© Tim Smith 2012-6. This work is made available under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

If you enjoyed this, you will probably enjoy PHP: A Fractal of Bad Design, which is even more cathartic.