Can you survive your Data Hiroshima?

Even expensive and top-of-the-line hardware is fallible. Last night (at the time of writing) my main workstation’s PSU burned. I mean, not soft-failed and powered down, I mean burned. With the acrid smell filling the room, I knew something went very wrong the instant I entered my study. I found my computer powered down, non-responsive. I wasn’t too worried because I knew that even if the computer went dead for good, I would not loose much data since, you know, I have backups.

Are you capable of surviving your own little Data Hiroshima?

Suggested Reading:The LATEX Companion

Frank Mittelbach, Michel Goossens, Johannes Braams, David Carlisle, Chris Rowley — The LATEX Companion — 2^nd ed, Addison Wesley, 2006, 1090 pp. ISBN 0-201-36299-6

(Buy at Amazon)

I should have told you about this book a long time ago. The LaTeX Companion is the definitive guide to LaTeX, ideal for anyone using it on a daily basis (or almost, as I do) or anyone wanting to learn LaTex. LaTeX is a complex and sophisticated mark-up language aimed at producing better typography for mathematics and scientific work—in which it totally succeeds. As for Linux, LaTeX (and TeX) comes in many distributions, some more geared toward the humanities, other for science, and still other for exquisite “art” typesetting.

A must read for graduate students.

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On the web:

• Latex for Humans
• The Beauty of LaTeX
• The IRC channel #latex on irc.freenode.net

Upcoming GT / Conférence-Causerie for #programmeur on Freenode

The guys from the freenode channel #programmeur (irc.freenode.net) are Getting Together this saturday September 5th at 13h00 at the University of Montréal. The program: short (1h) talks about Distributed Version Control software, Numerical Stability, and Secure Networking.

Instructions to get there are here.

The cost of entry is 10$, mostly to pay for renting the room with media equipment. All are welcomed.

Short PWD in BASH Prompts

It’s not uncommon to have inordinately deep directory hierarchy on your computer, especially if you’re like me and you like to give significant names to your directory. For example, if you’re using a 80×25 terminal, the location /home/steven/download/Album Photo/2009/06 jui/20-22/21-008-St-Georges-de-la-Malbaie will cause your shell prompt to wrap around the shell window quite messily. Of course, you could show only the last directory’s name, say 21-008-St-Georges-de-la-Malbaie to continue with my previous example, but that’s a bit terse, especially if you end up on a directory whose name is unexpectedly short.

The correct solution, may be, is to arrange the prompt to show adaptively long parts of the current working directory up to a given limit, and abstract parts of the path using, say, ..., and make sure the result is legible. For example, /home/steven/download/Album Photo/2009/06 jui/20-22/21-008-St-Georges-de-la-Malbaie, using a maximum prompt length of 50 would get shortened to .../06 jui/20-22/21-008-St-Georges-de-la-Malbaie, which is already much shorter yet retained its legibility and meaning.

Suggested Reading: The Drunkard’s Walk: How Randomness Rules our Lives

Leonard Mlodinow — The Drunkard’s Walk: How Randomness Rules our Lives — Vintage, 2008, 252 pp. ISBN 978-0-307-27517-2

(Buy at Amazon.com)

For those who are interested in (but not already familiar with) probabilities and statistics, I would most certainly recommand this book. Mlodinow presents the basic concepts of probability and statistics by concrete everyday examples—and visually, whenever possibile, rather than through classical mathematical notation. He discusses psychological factors that make us so bad at estimating probabilities and understanding statistics. The concepts he presents are deep but the style is fluid and makes The Drunkard’s Walk an easy read.

[…]the human understanding, once it has adopted an opinion, collects any instances that confirms it, and though the contrary instances may be more numerous and more weighty, it either does not notice them or else rejects them, in order that this opinion will remain unshaken.

Francis Bacon, 1620

Filtering Noise (Part I)

If you own a car, you probably noticed that the speedometer needle’s position varies but relatively slowly, regardless of how the car actually accelerates or decelerates. Unless your speedometer is some variation on the eddy current meter, maybe the noise from the speed sensor isn’t filtered analogically but numerically by the dashboard’s computer.

Let us have a look at how this filtering could be done.

Suggested Reading:The UNIX-HATERS Handbook

Simson Garfinkel, Daniel Weise, Steven Strassman — The UNIX-HATERS Handbook International Data Group, 1994, 360. pp ISBN 1-56884-203-1

(Download, free)

This is one of the funniest piece of UNIX literature I have come across in a very long time. This book makes thoroughly fun of all the bizarre quirks and general user hostile friendly unfriendliness of Unix and all the stupid things the unexperimented (and sometimes experimented) users can do. Full of FUD and stupidity, this is a classic must read.

Not unrelated: Linux Hater’s Blog.

Suggested Reading: One Hundred Essential Things You Didn’t Know you Didn’t Know: Maths Explains Your World

John D. Barrow — One Hundred Essential Things You Didn’t Know you Didn’t Know: Maths Explains Your World — Norton, 2008, 284 pp. ISBN 978-0-393-07007-1

(Buy at Amazon.com)

This isn’t really a math book; there’s hardly any real math, it’s rather a book about math, or maybe more a book about math in our daily lives, more precisely about things that are indeed solved by maths in our daily lives. The reader needn’t a very high level of knowledge about mathematics to enjoy the read. If it contains several little gems¹, it also contains a number of chapters (as each of the 100 things you didn’t know you didn’t know is presented in a standalone chapter) that aren’t all that interesting. Still very much worth the read, though.

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¹ One I like particularly is the trick proposed by von Neumann to transform a biased coin into a fair coin. Let’s say we have a coin that lands on head with probability and on tail with probability (both quite far from ). Von Neumann observes that if you throw the coin twice, it will land twice on heads with probability , twice on tails with probability . But head followed by tail and tail followed by head have the same probability of . The quantity isn’t , but if each time we throw two consecutive heads or tails we “forget” them, keeping only the draws with one head and one tail (HT or TH), we get an unbiased, or fair, coin. Suffice to map HT to heads and TH to tails (or vice-versa) and we’re done.

Suggested Reading: The Big Book of Irony

Jon Winokur — The Big Book of Irony — St-Martin’s Press, 2007, 174 pp. ISBN 978-0-312-35483-1

(Buy at Amazon.com)

Winokur gives us the complete irony guide; from verbal irony—the most frequent one, when someone says something while clearly meaning the exact opposite—to auto-irony passing by morrisettian irony (irony mistook for coincidence or something else). You’ll learn a great deal about irony. Plenty of à propos quotes. Not exactly a book for the beach, but not very serious either.

CA_COSMO

Like me, you’re probably dealing with more than a single language at work and on a daily basis. If you’re from the US, it is not unlikely that you are speaking Spanish as well. Here, in Québec, we have English and french coexisting both at work and in our daily lives. Working at a computer, it means that I have two installed locales, one for the US Keyboard Layout and one for the Canada keyboard (formerly known as “Canadian French”) and I cycle between them constantly.

The fact that Gnome and Windows are smart enough to assign a keyboard locale per application or window allows me to chat in French in Xchat while coding using the US keyboard layout in emacs without explicitly switching the keyboard each time I switch windows. I’ve been doing this for so long I don’t even think of it. There are moment, though, where this model breaks a the seams.