GP code on Github

Some time ago I got an email asking for the code of one of my old papers. Unfortunately the code was lost. But that reminded me that I still had some other code that could actually be made available. Essentially, some Genetic Programming (GP) libraries that I did around seven years ago (which in turn started on some other old code that I had done before).

Fast foward some weeks and it’s now available on my github account these two GP libraries:

  • mini-gp: a minimalistic library that only allows simple tree-based GP
  • core-gp: a larger library that does GP, STGP, GE and GAs.

The code is released as is and it’s not even re-tested. Basically it’s there not to be lost in some old external hard drive. Still, it might be useful to someone who has some interested in GP and Common Lisp. The code it’s not particulary nice in some aspects and it even contains some over-engineering parts, but it’s was fun to do it and back then was very useful to me.

PS: I still have another library for Ant Colony Optimization that I would like to put it on Github too but it still requires a little clean-up. Hopefully in the near future it’s done.

EuroGP 2011 Best Paper Nomination

Just received an email with good news! The paper that I got accepted at EuroGP was nominated for Best Paper! The work that I started last year is starting to get some good feedback which is great :-) This paper describes the approach I have developed (in collaboration with Francisco B. Pereira) to evolve pheromone update methods for Ant Systems. The paper only deals with the TSP and the obtained results are promising since it outperforms MMAS. It is the first step to what I am working on, a Self-Ant System. The idea is to let the Ant algorithm find the best components that can help in solving the problem at hand. There is still a lot of work to be done but this is just the start.

PPSN 2010 and Evolving Ants

For the next days I will be attending PPSN 2010, in Krakow, Poland. I was here for the venue two years ago and it was a conference that I enjoyed very much. Mostly because of the model which is different from the standard ones (poster only format, absence of parallel sessions and a summary presentation of the papers by a senior session chair).

I will be talking about my lastest work which ties together two techniques that I’ve always wanted to do some serious work with them: Ant Systems and Genetic Programming. In this first paper, I am using GP to evolve an Ant System component. A key issue in AS research is how to design the communication mechanism between ants that allows them to effectively solve a problem. We propose in this work to evolve the current pheromone trail update methods. We tested with the TSP and initial results show that the evolved strategies perform well and exhibit a good generalization capability when applied to larger instances.

Doing this work was also very fun and it was all made in Lisp. I just need to improve the code a bit and package it nicely before making it free available.

Anyway, I wish PPSN 2010 will be an interesting conference!