Mailman 3 September 2006 - Edu-sig

Pre-PEP was: The fate of raw_input() in Python 3000
by Andre Roberge Jan. 7, 2007

Jan. 7, 2007

Hi-all, Having had a look at the discussion on the Python-3000 mailing list, I thought it was appropriate to write a draft PEP with the intent of eventually posting it on the Python 3000 list for "serious" discussion/future decision. This proposal could most certainly be strengthened, and the wording improved by a native English speaker with stronger CS background than I have. I have attempted to follow the standard recommended format (including providing both a motivation and rationale ... which seemed a bit redundant and an artificial split...) Feel free to make comments for improvement and even take over the "ownership" of this PEP. André ========================================= PEP: XXX Title: Simple input built-in in Python 3000 Version: $Revision: 0.1 $ Last-Modified: $Date: 2006/09/13 20:00:00 $ Author: André Roberge <andre.roberge(a)gmail.com> Status: Draft Type: Standards Track Content-Type: text/x-rst Created: 13-Sep-2006 Python-Version: 3.0 Post-History: Abstract ======== Input and output are core features of computer programs. Currently, Python provides a simple means of output through the print keyword and two simple means of input throught the input() and raw_input() built-in functions. Python 3.0 will introduces various incompatible changes with previous Python versions[1]. Among the proposed changes, print will become a built-in function, print(), while input() and raw_input() would be removed completely from the built-in namespace, requiring importing some module to provide even the most basic input capability. This PEP proposes that Python 3.0 retains some simple user input capability, equivalent to raw_input(), within the built-in namespace. Motivation ========== With its easy readability and its support for many programming styles (e.g. procedural, object-oriented, etc.) among others, Python is perhaps the best computer language to use in introductory programming classes. Simple programs most often need to contain a means to provide information to a user (output) as well as obtaining information from that user (input). Any computer language intended to be used in an educational setting should provide straightforward methods for both input and output. The current proposals for Python 3.0 [1] include a simple output pathway via a built-in function named print(), but a more complicated method for input [e.g. via sys.stdin.readline()], one that requires importing an external module. Current versions of Python (pre-3.0) include raw_input() as a built-in function. With the availability of such a function, programs that require simple input/output can be written from day one, without requiring discussions of importing modules, streams, etc. Rationale ========= Current built-in functions, like input() and raw_input(), are found to be extremely useful in traditional teaching settings. (For more details, see the discussion that followed [3].) While the BDFL has clearly stated [3] that input() was not to be kept in Python 3000, he has also stated that he was not against revising the decision of killing raw_input(). raw_input() provides a simple mean to ask a question and obtain information from a user. The proposed plans for Python 3.0 would require the replacement of the single statement speed = raw_input("What is the average airspeed velocity of an unladed swallow?") by the more complicated import sys print("What is the average airspeed velocity of an unladed swallow?") speed = sys.stdin.readline() The removal of raw_input (or equivalent) would not significantly reduce the built-in namespace while it would steepen significantly the learning curve for beginners. Specification ============= The built-in input function should be totally equivalent to the existing raw_input() function. Open issues =========== With input() effectively removed from the language, the name raw_input() makes much less sense and alternatives should be considered. The various possibilities mentioned in various forums include: ask() ask_user() get_string() input() # rejected by Guido prompt() read() user_input() References ========== .. [1] Miscellaneous Python 3.0 Plans (http://www.python.org/dev/peps/pep-3100/) ..[2] The fate of raw_input() in Python 3000 (http://mail.python.org/pipermail/edu-sig/2006-September/006967.html) .. [3] educational aspects of Python 3000 http://mail.python.org/pipermail/python-3000/2006-September/003589.html Copyright ========= This document has been placed in the public domain.

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Calculus with Stickworks (more Gnu Math)
by kirby urner Sept. 30, 2006

Sept. 30, 2006

I've amended stickworks.py a little to show how the basic ideas of differential calculus might be spelled out in Python. First: Take a traditional classroom Polynomial with enough roots to make it wiggle up and down (just come up with some factors), then tweak the vertical scale to keep VPython from zooming out 3 miles just to take in the view. def snakeywakey(x): """ Polynomial with x-axis crossings at 3,2,-3,-7, with scaler to keep y-values under control (from a plotting point of view) """ return 0.01 * (x-3)*(x-2)*(x+3)*(x+7) Second: Include a generic derivative taker that expects a function as input, and returns a function that evaluates to approximately df(x)/dx at any x, assuming whatever you need about continuity and so on. def deriv(f, h=1e-5): """ Generic df(x)/dx approximator (discrete h) """ def funk(x): return (f(x+h)-f(x))/h return funk Third: Graph them together in two different colors. See how a diving slope means a negative derivative, while a leveling off means derivative = 0 (crossing x axis) and so on. Eyeballing the two curves together is a big part of "getting" that the green guy is talking about the *slope* of the red guy at the same x. # domain generators d1 = dgen(-8, 0.1) d2 = dgen(-8, 0.1) axes(-8,5,0) deriv_snakeywakey = deriv(snakeywakey) graph1 = xyplotter(d1, snakeywakey) graph2 = xyplotter(d2, deriv_snakeywakey) Edge.color = (1,0,0) # make 4th degree snakeywakey red for i in xrange(130): graph1.next() Edge.color = (0,1,0) # make its 3rd degree derivative green for i in xrange(130): graph2.next() Here's a link to the picture (in reality, you can zoom in and rotate, look from all points of view -- part of our "beyond flatland" campaign, designed to remind people why we don't prefer the flatlanders' calculators to our flatscreen computers). http://www.4dsolutions.net/ocn/python/pycalculus.png >>> == RESTART ================================ >>> import stickworks Visual 2005-01-08 >>> stickworks.testmemore() Documentation: """ Some infrastructure for working with Vectors and Edges, including an xyplotter generator and axes maker. By Kirby Urner, Sept 13, 2006 Updated Sept 29, 2006: make color Edge class-level attribute add funky derivative demo refactor a bit Code: http://www.4dsolutions.net/ocn/python/stickworks.py For colorized source: http://www.4dsolutions.net/cgi-bin/py2html.cgi?script=/ocn/python/stickwork… Some relevant discussion: http://mail.python.org/pipermail/edu-sig/2006-September/007145.html http://mail.python.org/pipermail/edu-sig/2006-September/007149.html http://mail.python.org/pipermail/edu-sig/2006-September/007150.html http://mail.python.org/pipermail/edu-sig/2006-September/007312.html """ Kirby

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RSA pre college?
by kirby urner Sept. 29, 2006

Sept. 29, 2006

I've been brainstorming with other math teachers on the relevance of the Python modulo operator, a primitive right down there with + * / and -, but which doesn't get a lot of focus in traditional K-12 textbooks these days. Why not? The old answer was: Modulo Arithmetic belongs to something called Number Theory, which although a have for math purists, has precious little to do with the real world, and so we should focus on basic arithmetic (the "big four" operations) and leave the modulo stuff for college (and even then, only if they choose to become math majors). The old answer is full of holes of course. We have Modulo Arithmetic devices all over the place in every day life. Clocks, for example. Indeed, the individual columns of our positional notation, are simply Modulo Stacks with carry (hit the Modulus, pop the stack, carry 1, restore 0). Furthermore, we now have RSA running in just about every web client, ready to frame your secure session with a web server authorized to accept your Visa charge (what out for phishing!). I think the new answer is closer to the mark: there's no excuse for avoiding Modulo Arithmetic, and if your school does so, that's a sure sign of mediocrity and you might want to pass that back to your parents ("mom, our math teacher said we we won't study Modulo Anything this year, but Bugs Bunny said it's important" (or was it Mighty Mouse?)). So once your school buys onto this bandwagon, maybe your teacher will deign to project a good shell. Python's is excellent, but not the only game in town. J's is wildly powerful by design (hyperdimensional arrays a favorite breakfast food), worth poking around in. Then there's GameMaker. Nothing wrong with playing in a Game Engine, though I think Gerald's Darwin @ Home is more impressive: he rolls his own, using the most minimalist Physics Rules, and starting with the earliest Java AWT, then moving to JOGL. Any EIG VPython killer app has yet to be started, let alone offered in beta AFAIK. Please update me if I'm wrong about that. For more on Darwin @ Home, watch Gerald's excellent Google Video, hosted in the left margin of Myspace.com/4Dstudios. In sum, I think RSA *will* be making inroads as a curriculum standard in many good schools, right up there with "differentiation by parts" as a relevant algorithm to know about. And one of the benefits is cryptography opens History, both fictionally and nonfictionally. Neal Stephenson has trailblazed extensively in this direction. One thread: RSA was stumbled upon in slightly different form by some British cryptologists, but classified immediately as "too dangerous" for the general public. MIT, with the push of needing a business class solution to an emerging real world challenge (i.e. the need to encrypt on the fly, based on any two parties making random contact through the Internet), had no incentive to classify (quite the reverse). Plus when the cyberpunks discovered the NSA was offering resistence (in part because of the British example -- her dutiful civil servants inspire respect in many corners), the lid simply blew off, with PGP coming out of New Zealand and paranoid geeks teaching their own mothers how to generate public keys (better protection than tin foil). Given this turgid history, it's somewhat understandable why high schools might choose to stay in the bleechers, leaving RSA to the big boyz 'n girlz to kick around. But that's not an optimum way to leave it, especially now that the patent has run out, and rolling one's own is not in violation of anyone's legal rights. At Saturday Academy, I like projecting that website where you're promised big Reward Money, if you're able to crack some of their Modulo Ns (i.e. public keys) into two constituent Probable Primes (an even bigger reward if p and/or q turn out Improbably Composite?). "Python: It's Not Just for War Colleges Anymore" -- probably won't fly as a bumper sticker, but I do find it funny (it alludes to its dark DARPA past). Put a goofy little snake with rolling eyes in the corner, with this funny Revolutionary War hat, a Blunderbuss in its coils. Reminds of Don't Tread on Me. Kirby

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The Internet of Things - Bruce Sterling
by Jason Cunliffe Sept. 28, 2006

Sept. 28, 2006

Bruce Sterling -- The Internet of Things http://www.itconversations.com/shows/detail717.html [runtime: 00:57:41, 26.4 mb, recorded 2006-03-06] 2006 O'reilly Emerging Technology Conference. Good stuff funny penetrating literate sensibilty to the role and presence of names and namespaces as technocultural signs and signifiers Another more recent version of his thinking expands on the ideas is his Keynote at Unicomp http://ubicomp.org/ubicomp2006/ In my mind highly relevant to the best of the debates which rage here {KU vs.AS} I like the way Bruce stresses the value and need for such dialogue and namespace consciousness ------ Jason

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what you can do in a shell
by Michel Paul Sept. 28, 2006

Sept. 28, 2006

Here's a case where I was able to weave Python into math class a little unexpectedly - The other day students were confused by why we subtract h in y = f(x - h) when we translate f horizontally h units. So I fired up Python and did a shell session with them. Here is something similar to what we did: >>> ## Let's define a function. Any function. It doesn't have to be too complicated. >>> def f(x): return 2**x - 1 >>> ## Now let's generate a table of ordered pairs: >>> for x in range(-5, 6): (x, f(x)) (-5, -0.96875) (-4, -0.9375) (-3, -0.875) (-2, -0.75) (-1, -0.5) (0, 0) (1, 1) (2, 3) (3, 7) (4, 15) (5, 31) >>> ## Now let's horizontally translate this function. >>> ## By how much shall we translate it? >>> h = 3 >>> ## OK, let's see ... we want to shift our domain ... >>> for x in range(-5 + h, 6 + h): (x, f(x)) (-2, -0.75) (-1, -0.5) (0, 0) (1, 1) (2, 3) (3, 7) (4, 15) (5, 31) (6, 63) (7, 127) (8, 255) >>> ## Hmmm ... what happened? >>> ## Our x values translated OK, but our y values are off. >>> ## In order to be a horizontal translation, our y values should remain the same. >>> ## Oh no! What can we do? >>> ## <discussion> >>> for x in range(-5 + h, 6 + h): (x, f(x - h)) (-2, -0.96875) (-1, -0.9375) (0, -0.875) (1, -0.75) (2, -0.5) (3, 0) (4, 1) (5, 3) (6, 7) (7, 15) (8, 31) >>> ## Ahh! That's better! >>> ## So, when we translate x by h, we preserve the y-value back at x - h: >>> ## y = f(x - h) This is the beauty of the Python shell - a math student doesn't have to know any Python syntax to be able to follow this. They can just see it as active Algebra. Sure, you have to make clear how the upper limit in range works, and you have to make sure they don't get confused when we're using "range" in specifying a "domain", but still, they were able to follow what was going on, and thinking the issue through in this way was helpful. Not fancy stuff, not OO, but useful.

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Python-powered Fab labs the next big thing?
by Paul D. Fernhout Sept. 28, 2006

Sept. 28, 2006

Dethe Elza posted about Fab Labs on this list in 2005. http://mail.python.org/pipermail/edu-sig/2005-April/004676.html A year later, here is a mainstream new article on them: "'Fab labs' deliver high-tech tools: MIT's fabrication laboratories aim to help developing communities find innovative solutions to local needs." http://www.csmonitor.com/2006/0927/p16s01-stct.html Excerpts: ... MIT opened the first international Fab Lab in Costa Rica four years ago and has sponsored nine others since then. Meanwhile, many more labs have opened on their own. "They're just sort of popping up," Lassiter says. "It's a good idea, and people want to do it." That's what is happening in South Africa, where the government has a stated goal of improving the country's science, technology, and manufacturing capabilities. ... "The high concept is to get these into the communities," says Naas Zaayman, who runs the Innovation Hub Fab Lab for Advanced Manufacturing Technology Strategy, a government program created to spread science and technology. "It's the idea that if you're somewhere in rural South Africa, and you want something for solar energy, you can go to a Fab Lab and make your own." ... Justinos Nkutshwev is one of the regulars. He sits at a computer, using the mouse to manipulate lines on a graphics program. He is building a bus, he says, and a generator to make it run. He is 15 years old and never used a computer before he came to the Fab Lab a few months ago. Now, he works with the lab's machines twice a week. "I come here because I can make interesting things," he says. Although the lab technically closes at 5 p.m., the staff regularly keeps it open hours later. Sometimes teenagers show up at staff members' houses on Sunday, begging them to unlock the doors. "They say 'We need to finish our projects, can you please open?' " Nkadimeng says. "It's great to see them so eager. There's no way to say no." === Looks like they use Python too: http://episteme.arstechnica.com/eve/forums/a/tpc/f/158007275731/m/615004070… "We primarly use the computer in each Fab Lab for running our computer aided design (CAD) and manufacturing (CAM). Our main 3D tool is BLENDER (pictured on the left above) which we are extending in Python (for example, see cad.blend) for use with our specific audiances. We also use SDRAW and PSTOEDIT for 2D design." http://cba.mit.edu/projects/fablab/tools.html Anyway, just fodder for the imagination -- nice having Python running these things. --Paul Fernhout

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Re: [Edu-sig] creating an interface vs. using one (Michel Paul)
by Dethe Elza Sept. 28, 2006

Sept. 28, 2006

Edupython, on google groups: http://groups.google.com/group/edupython --Dethe On 26-Sep-06, at 3:22 AM, Humphreys, Simon (Hills Road Staff) wrote: > What's the new competing list SIG? I would be interested in > subscribing if it gets me away from the incresingly irritating > 'noise' on this one ....... > > ________________________________ > > From: edu-sig-bounces(a)python.org on behalf of Dethe Elza > Sent: Mon 25/09/2006 17:25 > To: kirby urner > Cc: edu-sig(a)python.org > Subject: Re: [Edu-sig] creating an interface vs. using one (Michel > Paul) > > > > On 25-Sep-06, at 8:06 AM, kirby urner wrote: > >> I think the discussion re VPython was worth having. Differing points >> of view were clearly expressed about a matter of substance. >> >> Your assessment of the signal to noise ratio suggests you're >> wearing ear muffs. > > Hardly. It's an assessment that's been made many times, by many > people, some of whom have left the list because of it. In fact the > noise on this list caused at least one competing list to be started > just to avoid it. > > It would be one thing if Kirby trolled Art, or Art trolled Kirby, and > you each recognized it as that, but you both seem unable to resist > responding to each others trolls. Which is too bad, because you both > have valuable points of view and useful things to say, but I (and > surely others) have started to filter it out because we're tired of > wading through the pointless (and frequently juvenile) feuding. > > Now, as with any other time I've tried to step into this brawl to > break it up, I'm sure I will be told off for it and soon wish I'd > stayed in lurk mode. Oh well. > > --Dethe > > > When all else fails, men turn to reason. --Abba Eban > > > _______________________________________________ > Edu-sig mailing list > Edu-sig(a)python.org > http://mail.python.org/mailman/listinfo/edu-sig > > "The Brazilian government is definitely pro-law. But if law doesn't fit reality anymore, law has to be changed. That's not a new thing. That's civilisation as usual." --Gilberto Gil, Brazilian Minister of Culture

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Business in Education
by kirby urner Sept. 27, 2006

Sept. 27, 2006

So Arthur, in thinking more about your well-founded suspicion of the profit motive, when it comes to curriculum writing and standard setting (test making), I'm thinking we should go over in what ways the public schools, pre college, are already subject to commercial moneymaking. You may suppose I'm about to launch on another anti-TI tirade (but you'd be wrong; plus I just bought one for my daughter, the same kind "Mr. Bright uses" (an excellent teacher)). More, I'm drawing from personal experience with McGraw-Hill, Avenue of the Americas (28th floor, desk jockey under Nola Hague, peer-to-peer with Ray Simon, who got me the post). It was all about Texas and California, the states with the biggest school-aged populations. Mass publishers had to jump through their hoops, our kiss good bye any real chance for profit for hungry investors. Just pandering to the baby states (like New Hampshire) made *no* economic sense. So what's happened is Californians and Texans have realized their economic clout with New York publishing and have decided to politicize around that fact. I know less about the situation in Texas (let others tell that story), but California is pretty obviously laid out on the table over on Math-Teach. It'll be really easy to do the postmortems. The story Californians now tell themselves is: we were going down the sewer, mathematically, but now scores are on the rise and all because of a new State Standard championed by our Education Pope, one Wayne Bishop over at CalState (a competent teacher I'm sure -- I use some of his linear algebra thinking in Gnu Math as a matter of fact). Now that Wayne is Pope, we're hearing a lot more about Saxon and Singapore, as the two flagship tree-killer textbook series that Our Nation must embrace. And yes, their ambitions are National, what with the Department of Education obligated by law to pass judgement on textbook offerings, thereby giving Our Friends the Big Publishers in New York, access to the levers of power at the federal level (a known quantity high ground). Get the Ed Department to sign off on Everyday Math, and you've got your gravy train for the next fifteen years minimum (but good doobie bureaucrats need job security too, so stamp it with "more study needed"). What has all this to do with Python? Precious little, which is of course my point. Textbook publishing is profitable because at the K-12 level, it's all about rehashing. Colleges pioneer and explore (or used to), but K-12 never changes, or, if it does, hardly moves at all in Mathematics. The pictures get more ethnically diverse, the sidebars more loquacious, the binders stronger, the books heavier and more expensive. These are the only dimensions we care about. Math Content, meantime, remains Plain Vanilla Pablum, i.e. nothing serious, until we weed 'em and feed 'em (Calculus Mountain to weed 'em). So has our Python Nation any hope at all of propagating to more than homeschoolers and forlorn little one roomers on Shoshone Rez in someplace godforsaken? We beed to recruit too, after all, if our ethnicity is to survive. Not according to conventional radar (which the math-teach subscribers all deem me to be "under"). With New York holding Congress in hammerlock, and pesky politicos yammering "fuzzy" and "new new", screaming to high heaven to legislate Math from On High (the only way religious fanatics know to get anything), Python, open source, GNU, Linux, Ruby, tupuloid, Sims, Alan Kay, $100 laptop, are all doomed from ever impacting any mainstream child in one of our mainstream all-American public school K-12 classrooms, ad infinitum and ad nauseum (a little Kay goes a long way, I agree, but he's still powerful good medicine). Obviously there's something wrong with this overly pessimistic model, as we already know from personal experience, if dealing with teenagers personally (as I do, daily), that the above memepool is hardly esoteric. A lot of kids already know about this stuff, because they're *all* homeschoolers when they come home, and keep learning through the balance of their day (even sleep can be educational). They're out of school and smack dab in the middle of that Commercial Sector you're always so suspicious about (having worked in it for many years, our first meeting being in your home town's Financial District). And smack dab in the middle of the out-of-school Commercial Sector, is the breakfast cereal industry. Cheerios, Cheerios, Cornflakes & Grape Nuts, one of the most feared Capitol Hill lobbies in the history of our planet. They own Saturday Morning, a cartoon festival and clown show, puppets galore, and long the Fortune 100 focus for discovering Emerging Trends. Cartoons have snakes. Cartoons have pirates. So what candle do the print media Publishers hold, when it comes to comparing old dead language lead, flat-on-a-page XY somnambulisms, next to the EyeCandyLand of XYZ television? Nada, right? So I guess this is the truce I'm seeing emerging between us. You're wanting to marshal the troops to defend the Sanctity and Purity of Ivory Tower Virginity, to keep it free from that down and dirty Profit Motive (at least in any tainted sense -- high grades still sought after). All along, you've been supposing my Fuller School credential meant I was duty-bound to try to get passed you and your forces, as I tried for the End Zone of Academic Respectability. You wanted me to check my funny-looking pyrate hat at the door, be a good compromiser, give a little, in the interests of mutual respectability. Then we could join forces and champion Python together, on the same side of high walls (with Microsoft at bay outside). But how it turns out is more like this: I'm happy to leave you to that battle, and hope you keep winning it (need troops? just ask). But I'm content to leave Academia to its textbook fixations and focus on Saturday Morning, where my market researchers have "lazy fare" to just experiment and play with little kids' minds, beyond any oppressive scrutiny and control of those "too old for cartoons" fuddydud college professors (except maybe the semioticians -- they watch us agog (or "agrog" as the case may be)). You keep Academics respectable (I support you in that), and meanwhile I'll do like me Pyrate Captain taught me: engage in all out psychological warfare on the fringe, where few dare venture, and even fewer make it back. Python Nation is lucky to have recruited someone like me. Kids really love it when I "Talk Like a Pyrate" [sm].[1] Yar! [sm] [2] Kirby 4D Studios Portland "Open Source Capital" Oregon [1] http://mybizmo.blogspot.com/2005/09/talk-like-pirate-day.html [2] http://mybizmo.blogspot.com/2006/09/yar.html

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off topic
by Andy Judkis Sept. 27, 2006

Sept. 27, 2006

I know this has nothing to do with Python, but the following headline from eWeek made me laugh out loud: Novell, Intel Deliver Xen-Enabled Linux for Dual-Core Xeons Is it any wonder that people think we're Martians?

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Re: [Edu-sig] Getting psyched for Complex numbers
by Daniel Ajoy Sept. 27, 2006

Sept. 27, 2006

On 27 Sep 2006 at 12:00, edu-sig-request(a)python.org wrote: > Getting psyched for Quadratics and Complex numbers in October! > Kevin > This might give you an idea: http://mondragon.angeltowns.net/paradiso/NumerosComplejosAplicaciones.html Daniel

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