I've been working on Linux userspace SPI slave code for the OMAP35xx processor the Gumstix runs for a certain project. When it's more polished, I'll probably put up a copy here.
Knights of the lambda calculus @2009-11-08 21:12:52
For the past decades, it seems like the typical image associated with LISP and its dialects was that of hermit battle monks enlightened in the paths of Zen and lambda calculus, having at most a witty You Suck koan or two to spare for imperative-programming intruders daring to interrupt their musing over the beautiful nested structures of code before those are taken out with a swift brace throw before they even realize what has happened unto them, let alone get to draw their bulky proprietary arms.
I've been wishing to learn a "proper" functional language (SML, while neat in some aspects, essentially remains an academic toy) for a while now. LISP, as of late, appears to have been suffering from the huge piles of dust settling on it - most compilers/interpreters are rotten, broken and/or depending on bulky runtimes which make it hard to take it serious as a proper application development tool. Clean, from the Catholic University of Nijmegen, would have seemed a natural choice due to some past entanglements that shall go unmentioned, but, in fact, there was that other functional language it was derived from which has been gaining much more of a foothold lately. Haskell borrows SML's friendly typing system, while being packed with some pretty damn sweet constructions that exploit the awe-inspiring, though kind of opaque to channel, power of its lazy evaluation system (deliberately avoided in SML), possessing a well-isolated imperative subsystem (through monads) for "real-world" tasks, having a reasonably good machine code compiler and performing well enough to be given a chance even if it's probably never going to be quite up there with GNU's C/C++ compilers.
Here's some code I wrote up for the sake of testing, calculating multinomial expansions (i.e. expansions of terms like (x_1+...+x_n)^k, a still pretty well-known and useful generalization of the stock binomials):
import System
import Data.List
facs = scanl (*) 1 [1..]
fac n = head (drop (fromInteger n) facs)
-- multinomial a b = (x_1+...+x_a)^b in (F,[p_1,...,p_a]) pairs for Fx_1^{p_1}...x_a^{p_a}
multinomial :: Integer->Integer->[(Integer,[Integer])]
multinomial a b = let premultinomial :: Integer->Integer->[[Integer]]
premultinomial 1 b = [[b]]
premultinomial a 0 = [[0|q<-[1..a]]]
premultinomial a b = [ q:p | q<-[0..b], p<-premultinomial (a-1) (b-q) ]
in map (\r -> (fac b `div` (foldl (*) 1 (map fac r)),r)) (premultinomial a b)
main = do args <- getArgs
putStrLn( show (multinomial (read $ head args) (read $ head $ tail args) ))
(If called with 3 5 as command line parameters, its output is
To spin on the previous metaphor, Haskell might be what happens if you take those venerable monks and provide them with leather longcoats and machine guns; for the reality-warping powers to complete the Matrix metaphor, I wouldn't make anything short of beating well-written C in performance count.
I should link this post on comp.lang.lisp - they would _lynch_ you ;-)
Seriously, I dont know which Lisp-Compilers you have tried.
Maybe you focused too much on scheme - yes, there are a lot of toy-scheme-implementations, a strength of scheme is that it is rather easy to implement a simple scheme-interpreter and compiler, and therefore have an easy way of trying out new concepts.
Common Lisp, instead, is a huge standard with less compilers. The only widely used ones requiring a runtime are CLISP (which has its own VM, and wasnt made to be fast rather than being a scripting-tool) and ABCL (which was made to run under Java and therefore of course needs the Java VM).
ECL uses C and (inline) assembler as an intermediate layer to produce executables.
SBCL (probably the one which is used most) and OpenMCL/Clozure can produce stand-alone-executables and compile directly to native code.
And of course, the commercial ones (LispWorks and Allegro CL) also can do that.
But well, if you like Haskell more, then use it. But dont mix up both. Haskell is a purely functional language, while Common Lisp is - from today's point of view - rather "imperative" (actually, it is a "multi-paradigm" language).
If you have an hour to fork off and don't have any deeper pre-existing expertise in the field, do watch this video. It contains a presentation by Lawrence Krauss on, as one might be tempted to summarize it, "life, the universe and everything", or more precisely a layman-friendly speedy-thing-goes-in overview of modern cosmology, its view on the history and the future of the cosmos-at-large.
It is 3AM and I have to get up for classes in 5 hours and 30 minutes. Nevertheless, a friend's recent adoption of blogging and a short conversation on #acmlm meant that I just could not go to sleep without somehow modifying the blog's software and posting to it.
As you might notice, the whole layout now follows a more Wordpress-like scheme with multiple posts displayed on a page and comments hidden by default.
Speaking of comments, I actually would not mind one from you (yes, you, who is reading these lines at the moment) at all, just to see if I have any meaningful audience to talk to or it has been just the cold, unrelenting walls of the internet all along.
EU elections, seaborne scoundrels and an indeterminate waypoint @2009-06-08 18:42:15
As some of you undoubtedly will know, yesterday was the day of the EU parliamentary elections (and also some communal elections of neglectable importance in Germany, but let's not go there). Of quite natural interest to me was the performance of the various Pirate Parties we have in the EU now (though I'm still not sure if the Finns were able to run in the end) and I wound up spending most of the evening following, with a certain sense of excitement that I'm quite surprised I could even muster for something like politics, the local results flying in one by one.
Not at all surprisingly, the German Pirate Party performed best in the larger cities (and wherever broadband internet is available, one might argue), even achieving results like a 1.92% in Dresden (my current constituency), placing first among all the "minor" parties and sixth in the grand total) and the east, where a certain percentage of "protest voters" and people placing their cross next to whatever sounds most funny to them exists and the CDU/CSU mantrain isn't that developed. In the grand total, after heavy downbound drag especially by the rural areas of Southern Bavaria, this amounted to 220thousandandsomething votes or a rounded up 0.9%, which is a pretty surprisingly high figure for a country like Germany where the average citizen still groups everything internet into the "child's play" box. (Note how inane spam like the "Animal protection party" managed to score higher.)
When the first estimates arrived, it actually looked like both the Conservatives and the Greens were on the losing side - but you can't have everything at once, of course, so while the Conservatives wound up losing some 6-7 percent, the Green Party actually was one of the slight profiteers of the election. On the brighter side, the largest absolute gain in votes was scored by the Liberals, whose EU-level politics, unlike their federal ones, made a fairly positive impression on me so far.
The really interesting battlefield of this round, however, were the 18+2 seats that are assigned to Sweden (or should be completely once/if the Lissabon Treaty is enacted, which looks all the more likely now because the Irish got scared of going bankrupt all alone, but let's not go there). Slightly below the more optimistic prognoses, though, the 7.1% victory of the Swedes still feels almost unreal considering the circumstances and the general tone on their topics in the spheres they have set out for. From all I gather, this seems to mean one seat for them and another once the two additional seats kept back for the Lissabon treaty's enactment are enabled. While it is unclear whether they will join ALDE or the Greens-EFA yet (I'd hope for the former, but it's unclear whether they would be able to skew the position of their "enterprise-friendly" undercurrent in the copyright matter with just one and a half person...), I frankly don't expect much of a direct impact from this yet (though I'm still looking forward to disappointed and outright outraged reactions to the result from the copyright lobby) - the right signals, however, have been sent. Let's hope this was a starting point rather than a zenith reached by a unique series of mistakes by the opponents.
The other day, I peeked into 4chan /v/. Somewhere on the first page, there was one of the usual lengthy threads of game bashery that are typical for it; at the bottom of it, however, was a post that mildly struck my attention - "Cave Story and Yume Nikki are the only games that /v/ agrees to be good". I played the former - and liked it, needless to say - and have been in search of a similarly wholesome gaming experience ever since. Naturally, a game put in the same league as it by the merciless gamer dungeon that is /v/ would warrant a look.
So yeah... Yume Nikki. You are an, apparently female, what the English-speaking net resident would call basement dweller (though, technically speaking, your location is a room in an unnamed floor of a high-rise). You don't leave your room save for the dreary balcony which evokes memories of the depiction of East Asian lower-end living in Terranigma (think Yunkou). All you do is walking around, playing a video game about catching falling eggplants, writing in your dream diary and sleeping. The last point, however, is where the interesting things start.
After a countdown of 3 seconds has elapsed, you find yourself on your own balcony. There's still nothing to do here, so you can proceed into your room. You'll notice your eggplant game was replaced to randomly either display a blinking white comma/magatama or a full-screen loop of something between Atari graphics and Mesoamerican codices. A foreshadowing of what's yet to come.
At this point, your reservations about leaving through your room's door appear to be gone. Beyond it lies a circle of twelve doors, each leading to different points of an extensive, if not vast, world of interconnected, abstract, often psychedelic or outright disturbing/shocking dreamscapes, populated by strange creatures such as walking clocks or tall, thin women with distorted faces contact with which teleports you to any of a number of isolated spots across the world, leaving you with no choice but to wake up ([9]). Scattered across the world are effects which can be anything from a bicycle or knife you can equip yourself with to something that reduces you to your own severed head. While the knife provides you with the faculty of fighting your environment, the game's apparent main focus remains to be its nonlinear exploration aspect, backed by an extensive score of ambient dark, disturbing music that sets the mood skillfully. Two canned-review-in-a-sentence descriptions that came to my mind were "bastard lovechild of Earthbound, Clock Tower, Sayonara Zetsubou Sensei and Knytt Stories" and "one of the more interesting feverish dream experiences out there".
download link (look for videos on Youtube if you need them)
It was about time I made a new posting here anyway...
recent ongoings have made this appear as a sufficiently worthwhile endeavour.
"Project Chanology". A minor quake is going through the internet, and it's not the big truck's
tires having torn this time. Looks like, after all the moderately amusing, but, as a bottom line,
meaningless Habbo raids, Youtube crusades and TV show calls, the English-speaking part of the dark matter
and unexplainable background static of the internet that is "Anonymous" decided to double its dataforce for a
more noble cause at last. The initial spark,
apparently, was the DMCA-induced removal of a
Scientology
propaganda video featuring Tom "Emperor" Cruise off the series of youtubes.
Well... I kind of understand them. Unless you are a totally indoctrinated crackhead, there is just
no way you can equal this to anything other than hilarity-in-a-can with a grain of disturbing. It's
probably a cult's counterpart to leaked Paris Hilton sex videos.
Success so far was moderate-to-decent, with most of Scientology's websites having been going back and forth
between down and slow during the past days and high-ranking Scientology officials being forced to acknowledge
the ongoings in spite of their apparent reluctance to; still, much more than one would have expected after
the amount of controversy in the
spawning thread. Of course, one might question the purposefulness of the measures taken - as Sapient from
RRS put it, "[...] it's easier to tell that Scientology is a fraud/con game if the website is online.".
As the title I picked for this entry implies, however, I think the meaning of this is further reaching than
a psychic capitalist cult being targeted by a bunch of hackers on steroids. The clash that is taking place here
is nothing short of one between the arguably most significant group of "ruthless exploiters" (assuming the broader
sense of "exploit" here) of the "net world" and their counterpart in the "real world"; indeed, in the reports
of certain media outlets on this (*eyes Skynews*), a certain tendency to side with Scientology motivated out of
an implied outrage along the lines of "they are treading on our lawn", grouped with a kind of arrogance reminiscent
of "this is a matter for adults, how dare those kids interfer" - except replace "adults" with "real world
authorities" and "kids" with "geeks" or something. (Speaking of which, I was quite amused to see that word being taken
as an insult for the first time in the course of all the hours I spent on the tubes so far a while back -
somebody polled me to ban somebody from an IRC channel where I had operator status for calling him one)
If the CoS is smart enough here, they could well exploit the chance to team up with all the ??AAs, global player industries
and whatever else there is floating around to form a lobby of unseen before scale for further restrictions to be imposed
on the internet - starting with Fox News and their exploding vans, brick after brick are laid out for depicting
it as a brooding place for hackers on steroids and terrorists who destroy people's lives
and have the cheek to dare challenge real-world structures. Oh well... thanked be the man who came up with public-key
cryptography.
The shortage of any visible retaliation measures á la CoS does invoke an uncanny "silence before the storm" feeling though...
Rise of the machines... or was it "fall" @2007-11-03 02:43:14
listening to: Antonín Dvořák - Slavonic Dances
The tendency of computer equipment troubles to leave you along for a long time to suddenly appear in bunches might really produce the impression of some kind of malicious higher force being involved, sneakily waiting for a convenient moment to let you take the full blow of technical malfunctions, general hardware inaptitude and software bugs. Of course, common sense says this is bogus... but I think common sense died the usual way alongside with my NAT router earlier today (which started the quite impacting four-hit combo) and still is taking its time to reboot.
Said NAT router's slow and painful demise was almost instantly to be followed by a sudden and inexplicable
freezedown of my desktop machine; the forceful reboot and chkdsk run to follow it left, among other things I have yet to discover, my foobar2000 playlists (I'm glad I backupped those...) and half my Trillian contact list
(meh, those guys were annoying anyway...) in ruins. Oh well.
Fast forward to 30 minutes ago. As usual, after getting yelled at to shut down and go to sleep by mom for nearly an hour, I decide to do my everyday switch to using my indispensable laptop computer in bed.
*plug in*
*press power-on button*
...
Loud clapping noise.
Lights go off, distinct smell of gunpowder (Why gunpowder? ...tomorrow, I'll so have a look at the warranty bill. If it "just so" happened to expire within the last two days, I'm going to laugh) fills the air.
"Oh well", I think, "looks like I'll have to go to sleep early today..."
Having booted up the laptop (now battery-powered) and logged in, I am confronted with yet another surprise, which, on its own, might be moderately interesting and probably even worth taking a screenshot of and posting on some board. The object in question is a dialogue box not unlike the well-known "application x crashed, would you like to send some unrelated personal data to Microsoft?" window. Except modal, repeating itself in an infinite loop and telling me that explorer.exe was shut down "for security reasons". No further explanation. Great success.
As a bottom line, I am now logged into the non-administrator account and enjoying my remaining 39% of battery. I'll probably have to think of something to do for another 2 hours...
On the topic of Old Chinese, landscape, complaints management and stereotypes. @2007-10-26 19:45:40
listening to: Masanori Oouchi, Masanori Adachi, Aki Hata, Hiroshi Kobayashi, Michiru Yamane - Rocket Knight Adventures - Stage 3
So I once again spent half the night clicking my way through the ill-organized, redundant and surprisingly large-scale linguistics-related article web of Wikipedia, entirely forgetting to prepare for a geography test and only getting 4 hours of sleep as a result. Great success. <_<
Either way, Linguistics is awesome. Sometimes I wish it wasn't madness for me to pursue anything other than a computer science degree.
This is a truly delightful read, unless you happen to be in the lower half of an MMORPG's population ORDER BY iq DESC.
On a further note, I never expected the anime fansubbing trade to be so tedious.
Burner, from the Janus IRC channel, offered me a position and, unable to refuse to anything as usual,
I accepted without even knowing what series it would be. Well, I was soon to
find out. The setting of the show appears to be one of those typical
butchered European middle age themes - in particular, the historical event that inspiration is obviously heavily drawn from is
the invasion of the Turks/Ottoman Empire, which is represented by islamist-looking, turban-wearing fanatics calling themselves the
"Sabulum Empire" and worshipping some kind of unrevealed relic (?) referred to as アルケ. (We rendered it as "ark", but its pronunciation
clearly distinguishes it from the "ark" in the series title.) The real-world story, however, had smelly old men poking at each other with poles and swords.
You can imagine that's a rather hard to market concept... but no worries.
They didn't stick to it.
Suleiman I: "Fuck yeah, I wish I had giant humanoid battle robots back then."
Now that sounds like a massive point of concern, however the "western world" - which seems to be a wild mashup of
fairytales, Germany, England, France and Russia - has quickly conscribed its own flavour of secret weapon: a squad of magic-wielding, saucer-size-eyed mostly
female knights in sparse armour that can't be quite considered suitable for practical combat usage.
Now we just need some nurses and catgirls and we will have all anime clichés united into a single hyperdimensional chimaera that nourishes
on the fabric of spacetime itself.
Or maybe your brains.
Oh and, by the way, as you might have noticed, the blog is back.
Well if it's any consolation there's no catgirls. And paradoxically enough, despite there being girls' physicals, and several trips to the infirmary, there are no nurses. In the game at least.
Ailure[!8a5bcda98a @2007-10-27 16:18:10
Stupid anime cliches. At least some animes are making fun of them. :)
Hello and greetings from Cambridge, UK.