Mailman 3 July 2011 - Edu-sig

xturtle online via processing.js !?
by Jurgis Pralgauskis 28 Sep '12

28 Sep '12

Hi, I am struggling around with interactive online py tutorials with https://launchpad.net/projects/intro-to-code (ith might become securely sandboxed soon, as pypy made it possible http://blog.sandbox.lt/en/WSGI%20and%20PyPy%20sandbox :) but one more thing is I'd like to let access xturtle functionality online - one possible way could be triggering tkinter to save its canvas to ps, and then convert them with imagemagic and show via web (animated gif or static) - but if pyjamas can render GUI for js (http://www.google.lt/search?&q=pyjamas+python ), mayby there is a way to **translate turtle commands to processing.js analogues** http://ejohn.org/blog/processingjs/ would it be difficult -- how do you think? -- Jurgis Pralgauskis tel: 8-616 77613; jabber: jurgis(a)akl.lt; skype: dz0rdzas; Don't worry, be happy and make things better ;) http://sagemath.visiems.lt

4 6

re Python's "batteries included" meme
by kirby urner 10 Oct '11

10 Oct '11

As I watch students struggle with the: if __name__ == "__main__": concept (where to put it, what it does), it occurs to me we could be doing more to leverage the already well-worn "batteries included." What's different about Python? The rich libraries it comes with, including a cross-platform GUI IDE. That's one meaning of "batteries included". But in another sense we could speak of the generic module as a "battery" with the "if run top-level" logic having to do with battery *testing*. ==== python module ==== [ BATTERIES ] (functions, classes, global-to-module names...) if __name__ == "__main__": [ BATTERY TESTERS ] ==================== That changes the meaning a little more, to where each Python module is like "a battery pack" with its own set of "testers". One thing we do with battery packs is we "import" (promote) their internals within a top-level namespace that starts off in some other (alien) module. Another thing we do with battery packs is run them top-level namespaces on their own, perhaps depending on imports (outsourced resources). I'm not suggesting harping on this too much, just another slide that goes by, but a fun mnemonic, and reinforcing of an already approved / useful design pattern (see my previous post in this edu-sig archive for an example of this self-testing style, relying on doctest for services). Kirby

2 12

Re: [Edu-sig] Inexpensive robot teaching platforms
by Andy Judkis 22 Sep '11

22 Sep '11

Here's another possibility, 100 bucks, programmable in Jython along with several other languages: http://www.finchrobot.com/ Temp sensor, accelerometer, two IR sensors, two photodetectors. No batteries, it's powered off it's 15 foot USB cable, not sure if that's a bug or a feature. I haven't actually seen or used one. Cheers, Andy

3 2

Musings on PEP8
by kirby urner 19 Jul '11

19 Jul '11

I find myself thinking about PEP8 a lot, not that I have it memorized. Now that Unicode reigns at the top-level, we've got an influx of Chinese namespaces, Hindi namespaces, Cyrillic namespaces... a nice long list, and the PEP8 conventions regarding capitalization, while sensible in Latin-1, might not cover the new cases (I say "might not" with some sarcasm, or an innocent stare (playing it straight)). I've seen arguments in diversity-minded circles that straying from Latin-1 top-level will obliterate the open source nature of open source, with many a Chinese engineer welcoming the advantages of a world around simple base cases, the old ASCII, a mother tongue of computer scientists (more so than EBCDIC even (sarcasm again)). http://en.wikipedia.org/wiki/Extended_Binary_Coded_Decimal_Interchange_Code The inter-readability of Latin-1 means lots of headaches removed, like at least *something* positive came out of that Roman period (as a child of Rome, I get to sound chiding). The flip side argument, which I find more persuasive, is that one of the biggest barriers to diversity is over-reliance on Latin-1, and "just ASCII" in particular. I heard those cheers in Vilnius, when Guido talked about the brave new Unicode world. Google's blogger interface switches to Lithuanian automatically when that's your timezone, or however it's figured. Lots of alphabetical markings you might not find in Latin-1. http://controlroom.blogspot.com/2007/07/blogger-control-panel-in-lithuanian… The whole point of Unicode was to open up source code writing, as an occupation, to more than just Euro-English speakers. The bridge has been built and Python has already crossed over it. http://controlroom.blogspot.com/2007/11/unicode.html None of which is to say that knowledge of Latin-1 is dispensable. My first chapters in Naming and Ordering per MathFuture threads (also Cardinality vs Ordinality) starts with "mappings" (the usual approach to functions per Dolciani) with familiar glyphs (we're learning them anyway in learning to read a native language), pairing with ASCII and Unicode bytecodes. Yes, it's a long discussion (UTF8 vs UTF32 etc) but we're talking about time slices and repeated revisits in a spiraling trajectory (per Saxon treatments). So even if the bulk of your coding is in some Thai characterset, you're quite familiar with the lower 128 in the Unicode codespace. Python itself has 33 keywords and a large number of builtins, such that "average Python" might look like Romanji-intensive Japanese, i.e. "heavy on the Latin-1 pepper, other spices" (yet lots of room for top-level class, function, variable names, libraries stuffed with them, all outside Latin-1). These concerns have been a long term focus, and continue to be, as Python students I encounter may be there for work and that may mean using non-Latin-1 Python namespaces much of the time. Kirby

3 2

Re: [Edu-sig] Musings on PEP8
by Vernon Cole 19 Jul '11

19 Jul '11

> From: kirby urner <kirby.urner(a)gmail.com> > To: edu-sig(a)python.org > > I find myself thinking about PEP8 a lot, not that I have it memorized. > > Now that Unicode reigns at the top-level, we've got an influx of > Chinese namespaces, Hindi namespaces, Cyrillic namespaces... > a nice long list, and the PEP8 conventions regarding capitalization, > while sensible in Latin-1, might not cover the new cases [...] Remember that PEP 8 is a guideline, not a requirement, and that it is documented as: "This document gives coding conventions for the Python code comprising the standard library in the main Python distribution. " Any programmer may choose any style she prefers for her own use. If she is writing modules for the standard library -- and expects to have them accepted by the community -- then she will follow PEP 8. > The inter-readability of Latin-1 means lots of headaches removed, > like at least *something* positive came out of that Roman period [...] Yes, having taken a contract to maintain code where the author wrote his comments in Romanized Ukrainian, I have a great respect for non-English-native authors who take the time to learn English well. It is a terrible language to have to learn, I am told, but is the only one _all_ software engineers can be expected to know. Also PEP 8 states that: "Latin-1 (or UTF-8) should only be used when a comment or docstring needs to mention an author name that requires Latin-1; otherwise, using \x, \u or \U escapes is the preferred way to include non-ASCII data in string literals." Even then, I would hope that an author would include an Anglicized version of his name, so that I can recognize it when I see it again. The only alphabets I personally can read are Latin, Cyrillic, Hebrew, and Greek. If your name is in Cherokee, then please put (John Standing Bear) in ASCII along side it. There is a very good reason for this: standard library code must be readable for people all over the world. That's why a Dutch software engineer wrote a language in which all the keywords and commentary are in English. > > The flip side argument, which I find more persuasive, is that > one of the biggest barriers to diversity is over-reliance on Latin-1, > and "just ASCII" in particular. > > The whole point of Unicode was to open up source code writing, > as an occupation, to more than just Euro-English speakers. I disagree. The whole point of Unicode is to open up application writing, so that _users_ can see computer output in their own languages. A person who wishes to pursue code writing as an occupation must understand and use English -- or be relegated to producing work only for his own culture. In the modern "flat" world, English is the language of commerce and computer programming. Not being able to write understandable English is a severe handicap. My programs are written in Python, documented in English, and usable by persons of another language. For example, see CaesarCalc.py from https://launchpad.net/romanclass , which assumes the user to be able to understand pigeon Latin. Even then, I give the result of (XVI - XVI) as "Nulla" because I expect that most users will not recognize "Nvlla" as meaning "nothing." Here is sample output. Notice that, when it blows up the traceback is in Python with English explanations: <console dump> procer numerus hic:III - II I procer numerus hic:3 - 2 I procer numerus hic:3 - 3 Nulla procer numerus hic:2 - 3 Traceback (most recent call last): File "CaesarCalc.py", line 40, in <module> print (cvt(subtrahends[0]) - cvt(subtrahends[1])) File "/home/vernon/romanclass-1.0.1/romanclass.py", line 99, in __sub__ return Roman(self.__int__() - other) File "/home/vernon/romanclass-1.0.1/romanclass.py", line 85, in __new__ raise OutOfRangeError, 'Cannot store "%s" as Roman' % repr(N) romanclass.OutOfRangeError: Cannot store "-1" as Roman </console dump> IMHO, on the whole, PEP 8 is a pretty good document. -- Vernon

3 3

Re: [Edu-sig] General Programming Education
by mokurai＠earthtreasury.org 17 Jul '11

17 Jul '11

On Thu, July 14, 2011 11:20 pm, Corey Richardson wrote: > > I was discussing programing with some peers at an MIT summer program, and > many of them came from the "JAVA AND OOP!" type of places to the point that, > when the opportunity came up for them to learn the basics in a seminar, a > few said "Pfff, but python sucks. It's too simple". Is it just me, or should > simplicity be a Good Thing? </rant> http://www.pbm.com/~lindahl/real.programmers.html Real Programmers Don't Use Pascal > But, my real question to you educators is, which paradigm do you use when first teaching programming, and why? I'm working with a different age group than you, but I start by mixing object programming and procedural programming. I use Turtle Art in the Sugar education suite for One Laptop Per Child XOs, now ported to several kinds of Linux. We begin with one object, and we send it a stream of messages to tell it what to do. One of the advantages is that the program elements are snap-together tiles/blocks rather than text, so that it is impossible to mistype a keyword or make a syntax error. Another advantage is that the children learn to work directly with the parse trees of programs before learning to write them in linear text. Then we have a choice of transitioning to Python, supported directly within Turtle Art using program blocks; Logo, which we can create as an export option from Turtle Art; or the Etoys environment for Smalltalk, which can also do turtle graphics using tile-based programming. There are also stack primitives in TA, so that we can introduce RPN and FORTH concepts. I am working on a set of lessons on all of this. Tony Forster is also contributing topics handled in Turtle Art. http://wiki.sugarlabs.org/go/Turtle_Art/Tutorials Marvin Minsky (born 1927) You don't understand anything until you learn it more than one way. In Rebecca Herold, Managing an Information Security and Privacy Awareness and Training Program (2005), 101. We like to think that a child's play is unconstrainedbut when children appear to feel joyous and free, this may merely hide from their minds their purposefulness; you can see this more clearly when you attempt to drag them away from their chosen tasks. For they are exploring their worlds to see what's there, making explanations of what those things are, and imagining what else could be; exploring, explaining and learning are among a child's most purposeful urges and goals. The playfulness of childhood is the most demanding teacher we have. Never again in those children's lives will anything drive them to work so hard. The Emotion Machine We have many studies of successful introduction of programming in third grade, using a variety of languages, but we do not know how much earlier we can begin. Preschoolers can be introduced to Turtle Art with the game You be the Turtle. I have proposed a version of Turtle Art with icons instead of words on the blocks, so that we can test how much of it the preliterate can manage. There are several visual forms of digits that children can read directly by counting elements, usually dots or lines. I use colors for variable and procedure names, and skip over text input and output until later. My most advanced CS example, not suitable for very small children, is a Turing Machine implemented in Turtle Art. -- Edward Mokurai (默雷/धर्ममेघशब्दगर्ज/دھرممیگھشبدگر ج) Cherlin Silent Thunder is my name, and Children are my nation. The Cosmos is my dwelling place, the Truth my destination. http://wiki.sugarlabs.org/go/Replacing_Textbooks

2 2

General Programming Education
by Corey Richardson 15 Jul '11

15 Jul '11

I was discussing programing with some peers at an MIT summer program, and many of them came from the "JAVA AND OOP!" type of places to the point that, when the opportunity came up for them to learn the basics in a seminar, a few said "Pfff, but python sucks. It's too simple". Is it just me, or should simplicity be a Good Thing? </rant> But, my real question to you educators is, which paradigm do you use when first teaching programming, and why? My peers cite OOP because, frankly, it's the only thing they've learned and have heard that e.g. procedural programming is bad. Personally, I like to use procedural (this is in Python, of course) for as long as possible. I don't even mention objects for a while, they aren't necessary or even desirable in many instances. I love using games as a project, and that's when I swoop in and bring up objects. My segue are usually the monsters of a text based game. I don't have them design an object for everything because it introduces complexity without benefit. Of course, it's not as flexible/correct a program as it could be, but it's a nice slow ease into OOP. But it certainly isn't the ONLY paradigm out there, and certainly not the most useful for everything. Any other insights? -- Corey Richardson "Those who deny freedom to others, deserve it not for themselves" -- Abraham Lincoln

6 5

Re: [Edu-sig] General Programming Education
by Laura Creighton 15 Jul '11

15 Jul '11

In a message of Thu, 14 Jul 2011 23:20:06 EDT, Corey Richardson writes: >a few said "Pfff, but python sucks. It's too simple". Is it just me, or >should simplicity be a Good Thing? </rant> It is not just you. I think these people may be members of the 'misery loves company' crowd. ``It was hard for me to learn it, so it had better be hard for you, too.'' Or the ``suffering builds character'' crowd. Or the ``programming is an elite business -- we wouldn't want just anybody doing it´´. Possibly they just hate fun, and get annoyed at the idea that it might be fun to program in Python. I've met all of the above. Pity their students. Of course, some just have too optimitic a view of the human condition. They reason that there must be something good about all the complexity of java -- even if it is not obvious to them - or else we would have stopped using it already. They just need a lesson in the inertia of human institutions. <snip> >Any other insights? Python already has a lot of very nice data types. The dictionary is a wonderful thing. People should _use_ them. Many people who have been taught the OOP religion automatically refactor every dictionary they find into a class with attributes, because they think that this is in some way 'better'. This is dead wrong. If you refuse to use the very high level abstractions out of your VHLL, and only stick to the Low Level abstractions, then you might as well be programming in a LLL such as Java. That some of your colleagues apparantly did not recognise that the reason that Python is simpler is because it is a VHLL -- because simplicity in expressing ideas in the hallmark of a VHLL -- does not speak very well for them. Laura >Corey Richardson

1 0

(no subject)
by mokurai＠earthtreasury.org 11 Jul '11

11 Jul '11

Related to my suggestion of using Turtle Art as a starting point for Python and pre-calculus, you might find these Logo books useful for exploring another direction besides Python. Pythonistas are welcome to suggest comparable Python titles, of course. And remember, Turtle Art is written in Python, so this isn't complete heresy. ^_^ http://el.media.mit.edu/logo-foundation/products/books.html Teaching With Logo, by Molly and Daniel Watt Approaching Precalculus Mathematics Discretely, by Philip G. Lewis -- Edward Mokurai (默雷/धर्ममेघशब्दगर्ज/دھرممیگھشبدگر ج) Cherlin Silent Thunder is my name, and Children are my nation. The Cosmos is my dwelling place, the Truth my destination. http://wiki.sugarlabs.org/go/Replacing_Textbooks

1 0

Re: [Edu-sig] Python and pre-algebra
by mokurai＠earthtreasury.org 03 Jul '11

03 Jul '11

On Wed, June 29, 2011 7:15 pm, mary.dooms(a)comcast.net wrote: > > I teach 6th grade math and Python was suggested as a way to apply > pre-algebra concepts in a programming context. My programming background > consists of one C++ programming class. How do I begin? Python is one of several excellent options. Others are Logo, Smalltalk, and APL, all of which are available at no cost. I worked on a free APL for 8-bit computers before the Free Software movement got started, and I have friends working on APLs for current computers to put under the GPL. Assuming that your students know no Python, you could use the Sugar Labs Turtle Art approach to math and programming to get started. Turtle Art was designed for children to use for math, programming, and art, and has natural ways to move to Logo, Python, or Etoys/Smalltalk. FORTH, too, but most people don't want to know that. ^_^ (FORTH love if honk then) The question is, which pre-algebra concepts? Do you have a curriculum standard or a particular textbook in mind? Are there other topics of interest? I can write TA or mixed TA/Python examples, and show students how to do the same, and we could work together on lesson plans to share in the Sugar Labs Replacing Textbooks program. There are others with an interest in doing this. > Are lesson plans and small programs available, for example, Probably. There are well over 100,000 digital learning resources on the Net. You can find some of them on pages linked from http://wiki.sugarlabs.org/go/Open_Education_Resources We will need a substantial number of teachers to review them, compare them, and select those that do the best job making concepts clear in ways that will stay with students. > where students could write and > "drop in" a script that includes integers and the output would not only > calculate it, but see the relevance of it in a real world situation? There are many ways to do that. One of the weirder ones is my Turtle Art Turing Machine for addition. ^_^ http://wiki.sugarlabs.org/go/Activities/TurtleArt/Tutorials/Turtle_Art_Turi… More directly to your needs, Pippy is a Sugar activity that shows a number of Python examples that students can edit. For example, Fibonacci a, b = 0, 1 while b< 1001: print b, a, b = b, a+b Changing the 0, 1 in the first line changes this from a generator of Fibonacci numbers to a generator of the related Lucas numbers. There is a Pascal's Triangle program. Plotted mod 2, it reveals a Sierpinski fractal. Relevant Python resources include NumPy and PyGame. > Or, perhaps, the program controls a "wheelchair" robot and students would > write scripts to drive the robot at a certain speed considering the slope > of a ramp? See the Etoys tutorial challenge for programming a "car", and the robot program in Uruguay with robots controlled by Sugar software. http://www.flickr.com/photos/christophd/4827926508/ XO turned into a robot thanks to the Butiá project > As you can see, I am a novice, but I see great potential and am willing to > learn. Delighted to meet you. > Thanks, > > Mary _______________________________________________ > Edu-sig mailing list > Edu-sig(a)python.org > http://mail.python.org/mailman/listinfo/edu-sig > -- Edward Mokurai (默雷/धर्ममेघशब्दगर्ज/دھرممیگھشبدگر ج) Cherlin Silent Thunder is my name, and Children are my nation. The Cosmos is my dwelling place, the Truth my destination. http://wiki.sugarlabs.org/go/Replacing_Textbooks

4 9