Older blog entries for fxn (starting at number 28)

Work. We are rewriting the wrapper for CPLEX to use XML::LibXML (a Perl interface to gnome-xml ) instead of XML::Simple . We didn't anticipate input files could be that large. Now the Perl model of 4MB of XML is built in less than 3s (versus the former 50s) and it seems we can stay with Perl, at least in the prototype.

If we find the time, we would like very much to give a chance to lp_solve (perhaps through the wrapper Math::LP::Solve) and compare timings.

Home. I've been using FreeBSD in my laptop at home for some months. I have learned a lot of things because before I played with FreeBSD the only Unixes I had used were some GNU/Linux distros. However, I miss dselect, so I'll probably install Debian again.

Work. At work we are doing some integer linear programming related to sourcing. We are doing trials with a library from iLOG that resolves them like a charm, but have performance issues with the very XML that states the problem to be solved. We have written a Perl wrapper

XML problem -> CPLEX -> XML solution.

The XML input file can have 4MB and we are using XML::Simple by now in this proof-of-concept, which gives 50s for the creation of the Perl model of the XML against 6s for CPLEX to compute the solution. A SAX approach would be complicated, so If we were to write a real-life wrapper C would be necessary in my opinion.

Playing. I played Tetris in my laptop under MenuetOS then. I will boot it from time to time to learn more about this OS.

Music. l'll go to the Jamiroquai concert tonight. Looks great.

Lots of things have occurred since last entry: Took an introductory course to Shiatsu (20h), reported typos and comments to the documentation of the MIX Development Kit and to the essay Homesteading the Noosphere, wrote some code for MyAdvogato (nothing interesting), started a gym routine (I need to lose some extra Kgs) and solved those pending things one leaves to work out in holidays (which finished an hour and a half ago, any relativist physicians willing to do a charitable action out there? :-).

I would like to have dedicated more time to maths, but I didn't. I'll try to find some hours regularly next weeks for them.

More stuff in the TODO: install filters for my printer under FreeBSD and study a routine to maintain ports and packages updated. Find an IBM PS/2 keyboard, I have enjoyed for about a year and a half a Happy Hacking Keyboard Lite at work and would like to program with that old IBM keyboard now, if I found one. Ah!, yes, sleep, oh, well.

I have certified most of the active advogaters and don't need to get to their personal pages at Advogato so often. It seems it would be better to read diary entries from recentlog.html in this case (and I suppose there are people that prefer recentlog.html anyway), so next version of MyAdvogato will be a wrapper for that page as well.

MyAdvogato. links didn't render well the output because of a bug in the script I've fixed tonight. New flags have been added: boxes, labels and plain. The purpose of plain is to build a page suitable for text-based web browsers. This an screenshot of the current ouput rendered by links.

I have finished and enjoyed again Learning Perl and must address a pending issue with myself: I have bought some heavy must-reads over the last two years, I love them all, but I need to choose one and concentrate on studying it instead of reading all of them in parallel, which it's turning to be too dispersed to grasp them. They are (as of this writing :-):

• Advanced Programming in the UNIX Environment, by W. Richard Stevens,
• Paradigms of Artificial Intelligence Programming: Case Studies in Common Lisp, by Peter Norvig,
• The Art of Computer Programming, by Donald E. Knuth,
• Object-Oriented Software Construction, by Bertrand Meyer, and
• Modern Computer Algebra, by Joachim von zur Gathen and Jürgen Gerhard.

Once I finish the documentation of MDK I'll choose one and try to get focused on serious study. Advogaters' suggestions would be welcome!

No programming these days.

Mainly reading the documentation of MDK and the 3rd edition of Learning Perl, on behalf of the left side, and finished Soul Mountain, on behalf of the right one, it has been a pleasure. Now comes a book jao recommended, Island by Aldous Huxley, and Yoka Daishi's Shodoka commented by master Taisen Deshimaru. Shodoka is one of the four essential texts of Zen.

compiler: I disagree. None of my atoms make up Spain. My atoms are mine and nobody in the earth has the right to murder me like that, not to mention the reason having to do with the goverment or the army of the country I live in.

We humans lie to ourselves to justify atrocities identifying individuals with ideas or entities. If terrorists wanted to be fair they could do things that at least didn't hurt anyone that had nothing to do with their problems. But they don't.

Nations live inside our minds, murderers kill people and metaphorically, symbolically, they touch nations. But there is no room for poetry if we are talking about death. Go and choose another symbol if you are so kind, thanks. The whole thing is a fallacy that lies behind conflicts and wars all over history.

nmw: I think the reasonings you criticize are directly falacies, terrorists didn't hurt USA, and no historical actions can justify or explain that atrocity. God, USA is an entity, they murdered actual people. Those killers that pretend to punish a country killing even a citizen are plainly lying.

Please, let the people live.

hacker: I think the tragedy could have been planned in weeks: just take some fanatics, show them how to direct an already flying plane to an objective if needed (probably not), check out the timetable of commercial flights, assemble small groups to reduce the crew and rest of the passengers and distribute them. Sadly, it seems not that complicated for professional terrorists. It's macabre and spectacular, but simple in my opinion.