Month: March 2009


March 23, 2009 Programs No comments

Meet gdpen, a new “pen” program. gdpen converts vplot files to PNG or JPEG, or GIF graphics formats (including animated GIFs). Use it like this:

gdpen < file.vpl > file.png


gdpen type=jpeg < file.vpl > file.jpg


gdpen type=gif < file.vpl > file.gif

Other usual options are available.
gdpen requires the GD library at the compilation time.
Several other “pens” are under development:

  • cairopen – for outputting standard vector-graphics formats
  • svgpen – for outputting SVG directly
  • pdfpen – for outputting PDF directly
  • gtkpen/oglpen – for displaying plots on a screen (as a replacement for xtpen)

How do I convert an image file to an RSF file?

March 15, 2009 FAQ No comments

One option is sfjpg2byte. It requires the JPEG library to be present at the compilation time.

< lena.jpg sfjpg2byte | sfdd type=float > lena.rsf

Another option (suggested by Vladimir Bashkardin) is to use the convert utility from ImageMagick.

< lena.jpg convert - lena.gray
echo in=lena.gray data_format=native_uchar n1=512 n2=512 | sfdd type=float > lena.rsf


< lena.jpg convert - lena.rgb
echo in=lena.rgb data_format=native_uchar n1=3 n2=512 n3=512 | sfdd type=float > lena.rsf

Google Summer of Code

March 15, 2009 Celebration No comments

Michael Tobis has submitted a Madagascar application to the Google Summer of Code. Check out the ideas page.

Madagascar group on LinkedIn

March 15, 2009 Celebration No comments

The greatest strength of open source software is the community of users and developers, with fast, two-way lateral communication that enables quick learning and rapid feedback cycles. Communication between users is improved when they know each other’s backgrounds better.
To help users to better know each other, a Madagascar group was created on the LinkedIn professional networking site. Those of you who are members of LinkedIn, or are interested in becoming members, are welcome to join and to invite other Madagascar users. To keep away the ubiquitous spammers, admission to the group is subject to approval, but this will be granted as soon as possible to anybody who looks like a “real person”.
LinkedIn offers forum capabilities as well, but please note that this is not an attempt to shift communication from existing channels (mailing lists, wiki, Sourceforge bug/feature request trackers/etc). On the contrary, since social networking sites generally try to “lock-in” users, and are not open to non-users, I would strongly recommend _not_ using their discussion forums, but just using LinkedIn’s connection features to get to know each other better.
Please note that this is not an endorsement of either social networking sites in general or LinkedIn in particular. It’s just something entirely voluntary that some people find useful. For those of you who are not familiar with what LinkedIn is, a description can be found on Wikipedia.

Fractal heterogeneities and scattering attenuation

March 13, 2009 Documentation No comments

A new paper is added to the collection of reproducible documents:
Fractal heterogeneities in sonic logs and low-frequency scattering attenuation

Madagascar school at Delft

March 1, 2009 Celebration No comments

The madagascar event of the year is the School on Reproducible Computational Geophysics, which will be hosted by the Delft University of Technology on June 12-13, right after the EAGE meeting in Amsterdam. Attendance is free but registration is required. To register, send a free-form email to