Thursday, May 28, 2009

Who runs more?

I've finally finished the visualization for my grad school visualization class. We had to use data sets from the UCI Machine Learning Repository. I have choose the auto-mpg data set, which has data concerns city-cycle fuel consumption. This particular data set has 398 tuples with 9 attributes.

So I've decided to show which motor model (number of cylinders) runs more with one gallon.

The visualization is just bellow. I had computed the data using simple PHP scripts with PostgreSQL sql queries. With gnuplot, I plotted the output of the script, saving the plots as SVG files, which, using inkscape, I've made the proper manipulations to get this work.

Where to find CC stickers

Wikimedia Commons is a fine place to find Createive Commons stamps to be placed on our work.

But those which I was really looking for are at:

Monday, May 25, 2009

Mutexes and Conditions

I was googling around looking for some examples on mouse handling with the SDL library and I've found this interesting tutorials site:

I've found the mouse handling examples, but there were some other interesting examples.

There are three good examples on concurrent programming:
Perhaps the one which had called my attention monst was the "Mutex and Conditions", because of the possibilities on "Discrete Event Simulation".

Thursday, May 14, 2009

Friday, May 8, 2009

Speech recognition, first step to "Voice Picking"

When I was starting the Mindelo WMS project, I had read something about "voice picking". Since there, I was wondering how to build a linux distribution for warehouse management.

At, there is a "Speech Recognition Howto", but perhaps I should found something more specific at the "Speech Recognition in Linux" at the wikipedia

Thursday, May 7, 2009

Elegant XML parsing using the ElementTree Module

Mark Mruss, from the, wrote an interesting article on an "Elegant XML parsing using the ElementTree Module". I had a little project on my job on which I had to read some XML data and make some reports with them. I am using PHP to that, but after reading this Mark Mruss's article, I am regretting not have started with Python since the begging.

"XML is everywhere. It seems you can’t do much these days unless you utilize XML in one way or another. Fortunately, Python developers have a new tool in our standard arsenal: the ElementTree module. This article aims to introduce you to reading, writing, saving, and loading XML using the ElementTree module.

  1. Introduction
  2. Reading XML data
  3. Listing 1
  4. Listing 2
  5. Reading XML Attributes
  6. Writing XML
  7. Listing 3
  8. Writing XML Attributes
  9. Reading XML Files
  10. Writing XML Data to a File
  11. Reading from the Web
  12. Conclusion"
Read the entire article at

Monday, May 4, 2009

Soft body deformation

The wikipedia has a short entry on "Soft body dynamics" but it cites this interesting framework called SOFA.
"SOFA [1] is an Open Source framework primarily targeted at real-time physical simulation, with an emphasis on medical simulation. It is mostly intended for the research community to help develop newer algorithms, but can also be used as an efficient prototyping tool or as a physics engine." [1]
It is also multi-platform. As soon as I have some test written, I will put some shots here.

[1] SOFA (Simulation Open Framework Architecture). (2009, March 26). In Wikipedia, The Free Encyclopedia. Retrieved 14:01, May 7, 2009, from