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I like the idea of treemaps.


http://www.cs.umd.edu/hcil/treemap-history/index .s html


Hehe, it was originally made to see what was taking up all the room on an 80MB hard disk :)

There's various software available based on this concept, most working like "du", except that you get the results graphically. You typically see a large picture on screen of what directories and files are taking up the most space. It looks like a piece of Mondrian artwork, with the size of rectangles corresponding to the size of space taken, so it is easy at a glance to see what is hogging all of the disk space. It can be drilled down, of course, by clicking to zoom in.

A quick Google search revealed SequoiaView:


http://www.win.tue.nl/sequoiaview/


Unfortunately this only runs on Windows, but I'm sure there are similar Linux programs available.

• J. A. Hall, "Seven myths of formal methods", IEEE Software 7,5 (Sept. 1990), 11-19. ( quoted here)
• J. P. Bowen & M. G. Hinchey, "Seven more myths of formal methods", IEEE Software 12,4 (July 1995), 34-41. ( quoted here)

• J. A. Hall, "Seven myths of formal methods", IEEE Software 7,5 (Sept. 1990), 11-19. ( quoted here)
• J. P. Bowen & M. G. Hinchey, "Seven more myths of formal methods", IEEE Software 12,4 (July 1995), 34-41. ( quoted here)

Imagine if all the major computer makers had come up with different kinds of floppy disk in the early 90's, all incompatible with each other?

They did that. Now there are just two formats left to support in the world: PC (DOS) and Mac. Since Apple stopped shipping floppy drives five years ago, and Mac OS can read and write DOS-formatted disks just fine, DOS won.

And don't get me started on all the ways you can format a hard drive...

Why men (and octopuses) cannot juggle a four ball cascade.
The mathematical theory was proved wrong for octapuses and spideroids.

Steffen Gerlach's Scanner (see also his excellent Borland Delphi-based Civilization clone) and SequoiaView were invaluable back when my hard-drive was a puny 20 giger. I highly recommend you all get them and try them out.

P.S. Be sure to turn on the colour mode in SequoiaView.;)

I'd like to see that, too. When I first started with ham radio, I was by far the youngest person in the local amateur radio club. However, I'm 32 now and still it is an old man's game to me. If I go to the local amateur radio club, I find myself between old people, who lost touch with modern technology or just don't care. It is just not interesting to geeks anymore, people go out and buy the stuff rather than building it themselves (or at least modify it to suit their needs). Most of them are even too stupid (or too old?) to operate a computer. If it wasn't for a couple of guys I know from universities (Eindhoven and Twente) and a local ham who is still very active with VHF and up, I would have given up amateur radio completely.

It is hard to say, but I think amateur radio has become obsolete when internet and cell phones became common. Not that it really has lost its technical aspects (especially not if you are in cutting edge technology like microwave), but it just doesn't appeal to young people anymore. It's doesn't appeal to employers either, though I have studied electronics engineering, I found more (and better pay) jobs as a UNIX and software engineer than as an electronics engineer. On the other hand, it is because of fellow radio amateurs that I came into contact with Linux and Open Source Software. Maybe it does have its advantages, being both a computer and radio geek ;-)

73 de PA3FXW

The best illustration of this use is probably Sun's Starfire video. It's an amusing short film of what the future will look like, at least according to Sun. The centerpiece of the movie is a large, wraparound console that is not only touch sensitive but will automatically scan anything that is placed on it.

There would appear to be a copy of the movie here for anyone interested.

... when you can get one of these?

Games with full-screen character graphics are called "roguelike", after the 1980's game "rogue". IMHO, they're much deeper than most modern so-called RPGs.

Some of my favorites are angband, mangband, slashem and omega.

For general information, try this or that.

Accordig to this, we should be getting them in a year or 5

killed your kitten, while helpless

> Anybody know what NetHack's relation to Rogue is? The games are incredibly similar.

Basic answer here and here. You should be able to find more by googling for roguelike.

There is also a newsgroup for Rogue addicts (which is mentioned on the Falcon's Eye site): rec.games.roguelike.nethack.

Yeah.. Single variable calculus is single variable calculus no matter where you take it but I believe that in MIT they go through the material a little faster than in other schools and the workload given as homework or problemsets is enormous. I might be mistaken but I got the impression that MIT calculus 1 covers in a little over 3 months what other schools would spend the whole school year on.

One of the nice things with for example the math classes is that you can take the basic .01 version (nothing special just the usual stuff), .01A (spend six weeks on what most schools do in a full year), .013A (calculus with applications), .014 (LOTS of theory, everything proven rigorously, only future mathematicians need bother).

I should also point out that in addition to just the basic math classes there are roughly 150 additional courses(undergraduate and graduate combined) offered every year by just the math department with topics ranging from introductory courses in microlocal analysis to things like supersymmetric quantum field theories, cryptography/-analysis, wavelets, computational molecular biology, Stochastic Processes, Lie algebra, etc.. (yes there is lots of overlap between departmental topics)

There's also 3 dozen more departments to choose from all with rather extensive course offerings. Just the summary listing in the course catalog with a one or two sentence description for every course takes about 350 pages.

People going to mit tend to be little above average also. I've met few different students who are triple gold medalists in international math olympiads. Having looked at the questions and not really understanding where to even start with the problems I felt kind of dumb.. If you feel like being an mit math major take a look at this

This is more commonly known as Mancala in the US.

An adaptation (simplified) of the game was used as a problem in last year's International Olympiad in Informatics: see the description of the problem here. For a description of how to solve it efficiently, see this booklet.

This is more commonly known as Mancala in the US.

An adaptation (simplified) of the game was used as a problem in last year's International Olympiad in Informatics: see the description of the problem here. For a description of how to solve it efficiently, see this booklet.

Maybe not as well as others.

Loosely, I do understand the concept of RAID. I know there's even number qualifiers to describe the different variations of mirroring and striping strategies.

The problem, from what I understand, is addressing limits built into the specifications of the IDE interface. So, even if you have a 2 TB RAID system, if you interface it through an old IDE connector, you can't make it seem larger than a pre-set limit. Likewise, if the OS doesn't support the newer, better IDE interface, then you can't gain the size benefits of the RAID.

Maybe the limit is 137 GB (not 128 that I mentioned earlier), but newer IDE disks of 160 GB are out there.

I don't know if a TiVo can be made to support those larger drives in hardware (it uses a UDMA-66 connector) or software (they use some tested (i.e. old) version of Linux for PPC).

This site suggests that newer Linux kernels can take advantage of the ATA-6 specification that allows sizes greater than 137 GB.

Maybe not as well as others.

Loosely, I do understand the concept of RAID. I know there's even number qualifiers to describe the different variations of mirroring and striping strategies.

The problem, from what I understand, is addressing limits built into the specifications of the IDE interface. So, even if you have a 2 TB RAID system, if you interface it through an old IDE connector, you can't make it seem larger than a pre-set limit. Likewise, if the OS doesn't support the newer, better IDE interface, then you can't gain the size benefits of the RAID.

Maybe the limit is 137 GB (not 128 that I mentioned earlier), but newer IDE disks of 160 GB are out there.

I don't know if a TiVo can be made to support those larger drives in hardware (it uses a UDMA-66 connector) or software (they use some tested (i.e. old) version of Linux for PPC).

This site suggests that newer Linux kernels can take advantage of the ATA-6 specification that allows sizes greater than 137 GB.

Has anyone tried Dynamo?

As you can see, connecting this to a VGA output is more complex than just wiring the right LCD pin to the right VGA pin. You can probably use something like an AVR or fast PIC or a small CPLD to spit out an image from RAM, though (like this, for example). Then you need some way for your host computer to put data into that RAM. RS232, ethernet, or USB would all be reasonably easy to do.

If your panel has more controllerage attached, though, all bets are off --- it may be imitating a VGA monitor, it may be imitating an ISA video card, or it may be providing some private proprietary interface to whatever device it used to be attached to...

Look. Airlines save millions of dollars in real money by using these kinds of programs, and they're not going to quibble if it is implemented in Java. They pay *real* money for these kinds of programs, and getting serious companies to pay large amounts for solving these kinds of real-world problems is enough to say "I rock" even if one isn't living with Mom anymore. Point me to a documented case where Java handles these kinds of intense logistics problems, and I'll begin to give you some credibility.

Right around the time when you show me the Mona Lisa done in fingerpaint.

Considering your preferred example was a 3D-shooter game, I'm relatively skeptical about your opinion on world-class application development.

If you think anything in Java touches what CLIM has achieved, you obviously haven't even followed the link I gave and read what is there. You also ignored all the positive qualities of Emacs (ever try to program Word?) that I cited. I fully conceded at the outset that Emacs and MS Word are competing in different arenas. Lisp has a history of serious publishing tools (also not word processing). These solved, for example, the serious problems involved in generating large sets of documentation using hypertext. in 1985.

Again, I concede that MS probably didn't use Lisp to develop Word. The fact that there isn't a Lisp-based competitor probably is due to the fact that smart people don't try to compete in the same niche as MS, and Lisp is used by smart people.

Hi,

I'm going to unabashedly karma whore for a second because Nethack is my favourite game ever. I can't tell you the number of hours I wasted playing this (or other rogue-like games, such as rogue, larn, adom, or omega).

Here are some links to get you all started:

Nethack.org

One of the first and best Nethack pages, from the legenday Boudewijn Waijers

another Nethack homepage

A newer Nethack page

QT Nethack

An impressive graphical Nethack

The google Roguelike directory entry

the classic rec.games.roguelike.nethack

Happy hacking!

Hi,

I'm going to unabashedly karma whore for a second because Nethack is my favourite game ever. I can't tell you the number of hours I wasted playing this (or other rogue-like games, such as rogue, larn, adom, or omega).

Here are some links to get you all started:

Nethack.org

One of the first and best Nethack pages, from the legenday Boudewijn Waijers

another Nethack homepage

A newer Nethack page

QT Nethack

An impressive graphical Nethack

The google Roguelike directory entry

the classic rec.games.roguelike.nethack

Happy hacking!

Hi,

I'm going to unabashedly karma whore for a second because Nethack is my favourite game ever. I can't tell you the number of hours I wasted playing this (or other rogue-like games, such as rogue, larn, adom, or omega).

Here are some links to get you all started:

Nethack.org

One of the first and best Nethack pages, from the legenday Boudewijn Waijers

another Nethack homepage

A newer Nethack page

QT Nethack

An impressive graphical Nethack

The google Roguelike directory entry

the classic rec.games.roguelike.nethack

Happy hacking!

this page

I agree with this, but it might become even worse, people might not know there are problems at all:

Last year a TV program showed the insecurity of the home banking program (I'm not sure that's the right the english term) of the ABN Amro bank. It turned out that any commands were stored in a plain text before they were send to the bank's computer. Somebody wrote a program that changed the account number to which a user wanted money to be send. The TV program demonstrated how this program could be posted on a newsgroup as an update or patch.
After that it showed how an unsuspecting user (and if we look at the spreading of e-mail viruses, there are many unsuspecting users) could open the file. The program showed the banks logo and a progress meter while it was installing itself. After that the TV program showed that trying to send money to account A would instead be send to account B. Even worse, because the program by default shows only a name (unaltered) and not an (altered) account number, the error would be hard to detect.
Needless to say the ABN Amro wasn't happy, they would fix this problem ASAP.

A few days later I saw this story in our local University newspaper (the story is halfway down the page and it's in dutch). Two students from our university had detected the flaw almost a year before and reported it to the bank. The bank told them they would get back to them...

My point is, without actually writing a program that shows a security flaw, nobody might get to know about the flaw. The media isn't willing to do a special report on how someone might theoretically some day circumvent some security. They're only interested if they can show something to their audience.
And I think many companies a perfectly happy to let security risks exist if it saves them money.

--
Xagnix
(Xinix actually, but that username was already in use)

We weren't exactly the first site on the Web. Try http://www.w3.org/History/.

IBM's ThinkPad moels A20, A21, T20, T21 or X20 will fail to boot every OS (including Windows) after installing FreeBSD until the hard disk is removed from the laptop and the FreeBSD partition is wiped clean. This is because IBM DID NOT FOLLOW OPEN STANDARDS.

The Slashdot story on this was here, and the BSDToday story (which Slashdot copied) is here.

Details:

IBM uses a Phoenix BIOS in their Thinkpads. Phoenix chose not to do 3 minutes of research on the internet, and they didn't find Andries E. Brouwer's List of partition identifiers for PCs. Because Phoenix didn't care about Open Standards, they used partition type 0xA5 for their hibernation partition type. FreeBSD has used this partition type for years Andries's Partition Identifier page has been around since 1995.

At boot time, when the FreeBSD partition is seen (and thought to be a hibernation partition), the BIOS panics, doesn't know what to do, and the entire laptop is dead in the water, after FreeBSD is installed. The only fix is to physically remove the hard drive from the broken laptop, install it into a working machine, and wipe clean the FreeBSD partition.

IBM claims to support Linux, and they claim to support Open Standards. Yet they chose Phoenix for their BIOS, despite the fact that the recent Phoenix BIOS is non- Open Standards compliant. Even if IBM had no knowledge of Phoenix's bad choice, they share some culpability for not testing and checking. (In the worst case, IBM is hugely culpable for purposely and wilfully violating Open Standards.) IBM used to have a support page in which they said that they would not support FreeBSD on their hardware; they have taken the page down.

If IBM will not do 3 minutes of research on the internet and check for Open Standards before implementing something, so that they don't violate Open Standards, how long will it take before Linux is affected? How long will it take before IBM violates some Open Standard related to Linux?

If IBM will purposely chose a company that produces software which is not Open Standards compliant, and will not do anything to remedy the problem, how long will it take before they chose software from another vendor that directly and negatively affects Linux?

If Linux support means anything, then it means adherance to Open Standards. IBM screwed the pooch on this one. Maybe the fact that they've taken their page down means that they are going to fix the problem. Maybe it means that they are going to try to hide the problem and pretend it doesn't exist. They have not yet apologized.

Recommendation:

For now, I am boycotting all IBM products, including their RS6000 line. I urge you to do the same. This screw-up (with no apology and no fix forthcoming) indicates that IBM really does not care about Open Standards compliance.

Kenneth J. Hendrickson

• _____
• 
  ToiletDuk (58% Slashdot Pure)

Many countries name their science competitions "olympiads" or something like that. Here's a smallish list. By the way, the 41st International Mathematical Olympiad is being held in South Korea right now.

Instead of supporting Blizzard and their franchise, you could check out some great opensource projects that Blizzard basically repackaged, made real-time, added fancier graphics, and sold to Joe Consumer.

Rogue is the grandaddy of everything. Including Diablo. See where it all began.

Angband is my favorite Rogue-like. It has incredible depth, hundreds of monsters, and hundreds of magical items. #angband on Othernet usually has at least one developer in it.

There are also a number of Angband variants such as Zangband and Pernband. Zangband even includes a multitude of quests, for those who like a little story-line to their dungeon crawls. These can all be found at the Angband link above. Graphical Tcl versions of Angband also exist, for the graphics-needy.

Others include Nethack (a light-hearted, often humorous Rogue-like), ADOM , and Moria

So, instead of marching to your local EB, why not download one of these (I heartily recommend Angband) free games and save the 40$ that Diablo 2 would cost you? You could even contribute to the project, play with the source, or add your own monsters, items, and spells. Have fun!

Here are a few people's pages about Lisp Machines, for the curious (Some links are MIA; can anyone find a new valid address for them?):

• Symbolics machines: Peter Paine | Bob Kerns | [MIA] Rainer Joswig | dr. P.M.E. De Bra | Ralf Moeller | PT Withington
• LMI machines: [MIA] Joe Marshall
• There were other LISP Machines: Ti Explorers, Xerox Dandelions, etc... Check the FAQ for comp.lang.lisp, make a Google search, etc.

--

Back when I was seriously addicted to Nethack, Valkyries were my all-time favorite character class. They're tough, they're neutral, they start out with pretty good stuff, and best of all, they always get Mjolnir first when sacrificing at an alter. And with 25 strength (gauntlets of power), if a Valk throws Mjolnir it will return to her hand, making it an awsome projectile weapon that's also good for hand-to-hand combat.

Maybe not for calculus, but this facility is very useful when you study discrete structures. I've used it many times, found several connections between seemingly unrelated structures, and sometimes had to feel embarrassed for not seeing the obvious pattern myself.

In a similar vein, and very interesting for coding theorists, is this page. Set up by kernel and nethack hacker Andries Brouwer.

I'm surprised that nobody has mentioned formal methods for specification, design and implementation. Back in the 60s & 70s people like Dijkstra declared that programming was a mathematical discipline. Check out Seven Myths of Formal Methods for a summary that dispels the standard myths. This is also really good. Formal methods won't solve all problems, but they're useful.

You know, nobody builds bridges without mathematics anymore.

What? Software is more complex than bridges? People have mentioned design. Design is about breaking down complexity. Some people are good at it, most are bad. A good understanding of mathematics helps.

For the International Olympiads in Informatics, we Dutch require our team to consist of two boys and two girls. The girls are selected from the 2 or 3 female contenstants that take part in the prelimary rounds. (And of course the boys from the hundreds of male contestants.) If you want to see what happens at the international competitions, read this and search for "logo" and "zero points".