Category: r (Page 8 of 20)

Subsetting data

2013-05-07 / Luis

At School we use R across many courses, because students are supposed to use statistics under a variety of contexts. Imagine their disappointment when they pass stats and discovered that R and statistics haven’t gone away!

When students start working with real data sets one of their first stumbling blocks is subsetting data. We have data sets and either they are required to deal with different subsets or there is data cleaning to do. For some reason, many students struggle with what should be a simple task.
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Learning to code in R

2013-04-26 / Luis

It used to be that the one of the first decisions to make when learning to program was between compiled (e.g. C or FORTRAN) and interpreted (e.g. Python) languages. In my opinion these days one would have to be a masochist to learn with a compiled language: the extra compilation time and obscure errors are a killer when learning.

Today the decision would be between using a generic interpreted language (e.g. Python) and an interpreted domain specific language (DSL) like R, MATLAB, etc. While some people prefer generic languages, I’d argue that immediate feedback and easy accomplishment of useful tasks are a great thing when one is learning something for the first time. Continue reading

Gratuitous picture: just different hardware (Photo: Luis, click to enlarge).

Remembering server installation details

2013-01-08 / Luis

I’ve been moving part of my work to university servers, where I’m just one more peasant user with little privileges. In exchange, I can access the jobs from anywhere and I can access multiple processors if needed. Given that I have a sieve-like memory, where configuration details quickly disappear through many small holes, I’m documenting the little steps needed to move my work environment there.

The server provides a default R installation but none of the additional packages I often install are available (most people accessing the servers don’t use R). I could contact the administrator to get them installed, but I’ve opted for installing them under my user space. For that I followed the instructions presented here, which in summary require adding the name of the default folder (/hpc/home/luis/rpackages) for the local library of packages to my .bashrc file:
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Entry point to the R world. Same as ever.

An R wish list for 2013

2012-12-30 / Luis

First go and read An R wish list for 2012. None of the wishes came through in 2012. Fix the R website? No, it is the same this year. In fact, it is the same as in 2005. Easy to find help? Sorry, next year. Consistency and sane defaults? Coming soon to a theater near you (one day). Thus my wish list for 2012 is, very handy, still the wish list for 2013.

My R year

2012-12-24 / Luis

End-of-year posts are corny but, what the heck, I think I can let myself delve in to corniness once a year. The following code gives a snapshot of what and how was R for me in 2012.
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