As an exercise, I wrote some code to translate between ROS topics and services. Both directions turned out to be somewhat tricky. For example, I had to use a condition variable to coordinate updating data from the topic (which is taken care of behind the scenes in ROS using a provided callback) with calls to [...]
Maybe I’m underthinking the puzzle here, but it seems like heap sort solves the problem. It’s certainly meets the time requirements, but I wonder about the space issue. Does the array representation of a binary heap require a log number of pointers? More importantly, if this was my answer, would I get a job at [...]
I wrote a Python class for manipulating normal distributions. I use it as part of some code for GMMs (https://github.com/stober/gmm). I was looking for code that supported conditioning and marginalization on arbitrary indices. There didn’t seem to be any out there so I wrote this to fill in the gap (at least for Python).
I attended an interesting talk yesterday at ICDL-EpiRob on how one key property of developmental learning is trying over and over again at difficult tasks (like learning to walk). The experimenters found that a sense of elation would drive repeated failed trials which often led to better policies in the end, suggesting that being immune [...]
Awhile ago I took down my Pyrouette project on Google Code and moved it to Bitbucket. For the most part, the move has been a positive one, and has spurned a lot of work on my part improving the code. That work is nowhere near complete, but I’ve decided to make the repository public again. [...]
I have a rather, ahem, ad hoc system for organizing the files on my computer and in my daily life. I’ve also been pursuing a hobby of actually trying to implement algorithms that I read about in textbooks and papers. Combine all these with a middling memory and I often find myself wondering whether I’ve [...]
I was reviewing a paper recently that involved a new approach to solving n-armed bandit problems. Because I’m a diligent reviewer I spent some time refreshing my memory on what algorithms are used to solve these kinds of problems, and I thought I’d share a simple example here. An n-armed bandit is a kind of [...]
For some reason the code I’m writing requires a lot of mappings between different kinds of values, and I find myself trying to manipulate dictionaries in many ways. I wrote a simple function that reverses a dictionary: Then I remembered the setdefault method and was able to create a more concise function: Of course if [...]
This comic will now appear at the beginning of every talk I give between now and the end of time.
Prompted in part by a talk I went to yesterday, let me suggest that potential cognitive science/language researchers should probably read Chomsky’s review of Skinner’s Verbal Behavior very closely and carefully.