Wednesday, August 19, 2009

Mesh generator and Finite Element Solver


I was reading some papers at Universia, and I've found this one which references the Gmsh, a apparently simple mesh generator with an simple integrated CAD. It also has screencasts showing how to use it.
Gmsh was is developed by the professor Christophe Geuzaine for academic uses. I didn't read much, but Gmsh is apparently scriptable and the CAD tool is realy simple to use. I was planning to develop something very similar. Another cool thing at the professor's site is the project GL2PS, which the main idea, on convert OpenGL rendering in PS, PDF and SVG, I was also thinking in.
Professor Geyzaine had also written an finite element solver, the GetDP.
I am planning to use them all on some grad school works.
Another code on Finite Element Analysis is the SLFFEA, which stands for San Le's Free Finite Element Analysis, deserves note and is entierly written in Ansi C.

Tuesday, August 18, 2009

Warning against using pie charts

Bernhard Reiter had wrote a really nice warning against using pie charts, and he did put it on his plotting tool ;-)

Here is a peace:
"... Piecharts are generally not recommended to visualise information! Use bar- or pointchars instead if the quantities are important. Studies have shown that piecharts are hard to read if you actually have to answer questions about the numbers they represent. They look very pleasing and are used in a lot of places but they do not help to visualise information that well. Analytic thing person will read the percentages or values given on the legend or the chart itself and analyse them in their head. ... "
Check the full text at his web site.

Monday, August 3, 2009

Some tricks with gnuplot


I've been using gnuplot to embed graphics on my scripts for quite some time. And I liked it much.

Last month I was asked to maintain a legacy application which generates some live graphics using the JFreeChart class. It has some transparent animated 3D pie charts. So, I was wondering if I could do the same with a couple of scripts and gnuplot, generating an animated gif.

After googling a little, I've found these links:
And, with these new gnuplot features, I will try to do some cool scripts ;-)