Blog Archives

“[” and “[[” with the apply() functions

August 20, 2013
By
“[” and “[[” with the apply() functions

Did you know you can use "

Read more »

Electronic lab notebook

August 20, 2013
By
Electronic lab notebook

I was interested to read C. Titus Brown‘s recent post, “Is version control an electronic lab notebook?” I think version control is really important, and I think all computational scientists should have something equivalent to a lab notebook. But I think of version control as serving needs orthogonal to those served by a lab notebook.

Read more »

Read the source code

August 6, 2013
By
Read the source code

The other day, there was a bit of a twitter conversation about qqline in R. It made me think: how exactly is the line produced by qqline chosen? I seemed to recall that the line was through the first and third quartiles. An advantage of R is that you can just type the name of

Read more »

More on Chutes & Ladders

May 20, 2013
By
More on Chutes & Ladders

Matt Maenner asked about the sawtooth pattern in the figure in my last post on Chutes & Ladders. Damn you, Matt! I thought I was done with this. Don’t feed my obsession. My response was that if the game ends early, it’s even more likely that it’ll be the kid who went first who won.

Read more »

Chutes & ladders: How long is this going to take?

May 17, 2013
By
Chutes & ladders: How long is this going to take?

I was playing Chutes & Ladders with my four-year-old daughter yesterday, and I thought, “How long is this going to take?” I saw an interesting mathematical analysis of the game a few years ago, but it seems to be offline, though you can read it via the wayback machine. But that didn’t answer my specific

Read more »

Stack Exchange: Why I dropped out

May 13, 2013
By
Stack Exchange: Why I dropped out

Stack Exchange is a series of question-and-answer sites, including Stack Overflow for programming and Cross Validated for statistics. I was introduced to these sites at a short talk by Barry Rowlingson at the 2011 UseR! meeting, “Why R-help must die!“ These sites have a lot of advantages over R-help: The format is easier to read,

Read more »

Tutorials on git/github and GNU make

May 10, 2013
By
Tutorials on git/github and GNU make

If you’re not using version control, you should be. Learn git. If you’re not on github, you should be. That’s real open source. To help some colleagues get started with git and github, I wrote a minimal tutorial. There are lots of git and github resources available, but I thought I’d give just the bare

Read more »

Beware of grep with a list

April 2, 2013
By
Beware of grep with a list

Another R tip: beware of as.character applied to a list. Really, beware of grep with a list: You might have thought that the result would be just 1, but grep expects a vector of character strings. If the input is not that, it uses as.character(). Since the result of that starts with "c(", grep finds

Read more »

apply vs for

April 2, 2013
By
apply vs for

It’s widely understood that, in R programming, one should avoid for loops and always try to use apply-type functions. But this isn’t entirely true. It may have been true for Splus, back in the day: As I recall, that had to do with the entire environment from each iteration being retained in memory. Here’s a

Read more »

x[[c(5,3)]]

April 2, 2013
By
x[[c(5,3)]]

An R tip: Did you know that x] is the same as x]]? I should make more thorough use of this. In the help file for ] is equivalent to alist]...] providing all but

Read more »

Sponsors

Mango solutions



plotly webpage

dominolab webpage



Zero Inflated Models and Generalized Linear Mixed Models with R

Quantide: statistical consulting and training

datasociety

http://www.eoda.de





ODSC

ODSC

CRC R books series





Six Sigma Online Training









Contact us if you wish to help support R-bloggers, and place your banner here.

Never miss an update!
Subscribe to R-bloggers to receive
e-mails with the latest R posts.
(You will not see this message again.)

Click here to close (This popup will not appear again)