Mailman 3 December 2005 - Edu-sig

Brainstorming a new worksheet for 2006
by kirby urner 01 Jan '06

01 Jan '06

I'll be back to school on Tuesday, teaching another Python class. I'm about to throw together a web based worksheet for use in class (each student will pull it up in a browser). I'll be recycling a lot of familiar material. Just thought I'd brainstorm out loud about the contents, then whip it together, then come back here and share the URL. I want to review some of what we've done so far, include a lot of links, preview some of the content ahead. Topics: Google Earth, Celestia and Stellarium for orientation (hello world) Latitude / Longitude XML Python: shell mode primitive objects vs. collections Collections: list dictionary string tuple Expressions: list comprehensions Functions: getting started with sequences: triangular, tetrahedral numbers etc. Generators: same ground, different capabilities generator expressions ... That should be enough to get me going. I'll be back soon with that URL. It'll be a work in progress and I'll be open to feedback (positive, negative, neutral, indifferent). Kirby

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Re: [Edu-sig] Dynamic Worksheets
by Lee Harr 25 Dec '05

25 Dec '05

>What I'd like to provide is high bandwidth, over-the-wire learning >experiences, preferably on big plasma, with sensurround sound, that fully >leverage our capacity for imagination. Maybe I am a purist, but how does high bandwidth multimedia bring on the imagination? Seems to me that the kid who turns a rock in to a spaceship is using more imagination than the kid who sits back and lets the 3-d virtual reality space complex blast him in to orbit around the planet Boredium. It is a very fine line to walk. We want to keep their attention, of course, but we also want them to create things that we could never have imagined ourselves. If education is entertainment, where is the incentive to create? Maybe the boredom is an integral part of the educational experience. "These old fogies are so boring. There must be a better way to do this!" _________________________________________________________________ Express yourself instantly with MSN Messenger! Download today - it's FREE! http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/

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MS EXCEL Error
by Felix P. Muga II 24 Dec '05

24 Dec '05

IN MS EXCEL 1900 IS A LEAP YEAR I was writing a Python program to find the exact date of Easter Sunday for a given year after 1900 as an example for the course in Discrete Mathematics which I am teaching to 2nd year undergraduate students in my university. A part of the program calls for computing the number of days from 1900 to the given year. Hence, I have to consider the number of leap years. To derive the formula for finding the number of days, I used MS EXCEL since it has an excellent resource about DATES. However, I found out that MS EXCEL accepts the string '2/29/1900' as a legal date and even considers '2/29/1900' as a WEDNESDAY. Also, MS EXCEL recognizes January 1, 1900 as a SUNDAY. To verify these MS EXCEL results, I searched the WEB for the topic on PERPETUAL CALENDAR which showed that JANUARY 1, 1900 is a MONDAY and not a SUNDAY. Furthermore, I found out that a LEAP YEAR is defined as a YEAR which satisfies at least one of the two conditions: 1. The YEAR is a multiple of 4 and not a multiple of 100. 2. If the YEAR is a multiple of 100 then it must be a multiple of 400. Hence, 1996 and 2004 are leap years since they satisfy the first condition. Also, 1600 and 2000 are leap years since they satisfy the second condition. However, 1900 is NOT a LEAP YEAR since it is a multiple of 4 and a multiple of 100 but not a multiple of 400. The error in MS EXCEL is only confined to the dates from January 1, 1900 to February 28, 1900 (an ASH Wednesday) and the illegal date of February 29, 1990. Thus, a mistake occurs in the computation if these dates are involved. An example is the problem of finding the number of days between January 1, 1900 and December 31, 2005. It assigns a serial number of 1 to January 1, 1900 and a serial number of 39,448 to January 1, 2008. However, the correct serial number to January 1, 2008 should be 39,447. The error is due to the existence of February 29, 1900 (serial number of 60) as a valid date in MS EXCEL. Fortunately, I discovered this problem and I was successful in writing a Python program that returns the exact date of Easter Sunday for a given year after 1900. -- Felix P. Muga II, Ph.D. Associate Professor Mathematics Department Ateneo de Manila University

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Re: [Edu-sig] Dynamic Worksheets (Lee Harr)
by Daniel Ajoy 22 Dec '05

22 Dec '05

On 22 Dec 2005 at 12:00, edu-sig-request(a)python.org wrote: > If education is entertainment, where is the incentive to create? > > Maybe the boredom is an integral part of the educational experience. > "These old fogies are so boring. There must be a better way to do this!" > Edutainment, No thanks. I Prefer Playful Learning. http://llk.media.mit.edu/papers/archive/mres/edutainment.pdf Daniel ***************************** OpenWorld Learning http://www.openworldlearning.org

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Dynamic Worksheets (scrolling, embedded animations & testing -- credit-accruing)
by kirby urner 20 Dec '05

20 Dec '05

So I'm thinking the way to do worksheets is to think of a scrolling web page, with embedded applets, and with reader challenges built in, with some kind of automatic scoring (useful feedback). The style of the worksheet would of course reflect the artistic sensibilities (or lack thereof) of the author. I've been influenced by the O'Reilly 'head first' series: http://headfirst.oreilly.com/ Somewhere in a sidebar, or maybe even front and center, Python learners should see: mytuple = ( element, ) listcopy = [ comma, separated, elements ][:] {dictionary}[lookup] = newelement and variations on that theme. The point is to reinforce a lot of related concepts using nifty mnemonics. For example, it's not just that tuples are parenthesis-defined, but that a single element requires a comma. With lists, we address the need for a slice, if we want to avoid a double-naming the same referent in memory. With the last line, we illustrate adding to a dictionary using the assignment operator. This is but one example. Another would be: noun.verb(args) noun.state where noun = object; verb is for method (args = eatables); state could be an adjective (green), or even a property, with getter / setter verbs behind the scenes. For more on properties: http://mail.python.org/pipermail/edu-sig/2005-August/005059.html (ff. thread) An inheritance path might be Class0 (object) -> Class1 (Class 0) -> Class2 (Class1) -> Class3 (Class2) where these nouns are class objects, superclasses going left, subclasses going right. These little alphanumeric mnemonics need to be abetted with multiple pictures. For example, a complex number sequence, generated from some arbitrary point on the complex plane, per Mandelbrot or Julia, should loop through Python stepwise, while doing something graphical directly adjacent (a pixel attains some color value, vectors swing around -- many options). I'm influenced here by J Language pedagogy, which goes to great lengths to tie up with "parts of speech", thereby making "grammar" the right word to apply when studying J's structure and syntax. http://www.4dsolutions.net/ocn/Jlang.html (Kenneth Iverson himself helped me squish some typos before he died -- I think there're still one or two). These "Prosperos Books" (some from O'Reilly?), could be used in a community college setting, sometimes in testing situations i.e. under controlled conditions that measure student performance in some pre-agreed-upon way. Related reading: http://mybizmo.blogspot.com/2005/12/another-interesting-day.html (click in MER in "After dark, I wrote an essay on MER<http://mathforum.org/kb/thread.jspa?threadID=1310716&tstart=0>for our KBE <http://worldgame.blogspot.com/2005/10/saturday-academy.html>,...") Kirby

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Python as a CS1 language: Reference(s)?
by Radenski, Atanas 19 Dec '05

19 Dec '05

Hello all, I am writing a paper on my experience with Python as a CS language at Chapman University, California. I know Python has been used as CS1 language in some colleges/universities, such as: 1. Wartburg College (IA, USA) 2. Georgia Tech (GA, USA) 3. University of California Irvine (CA, USA) 4. Simon Fraser University (BC, Canada) 5. Center College (KY, USA) 6. Chapman University (CA, USA) Is there a comprehensive list of institutions that use Python? Can you provide information of other institutions, not in the above list? Any references to related resources will be appreciated. Bets regards, Atanas Atanas Radenski mailto:radenski@chapman.edu http://www.chapman.edu/~radenski/ In this world, time and space are the same -- Richard Wagner ("Parsifal", 1882)

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The Bridges Conference: Mathematical Connections, in Art, Music, and Science
by Arthur 16 Dec '05

16 Dec '05

http://www.lkl.ac.uk/bridges/call.html

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"The study of fixed points has been at the foundation of algorithms"
by Arthur 15 Dec '05

15 Dec '05

A bit of a windy road: starting, as usual, with the personal frame of reference.... PyGeo's current implementation supports the exploration of the geometry of complex numbers, and therefore speaks Mobius transformations. http://pygeo.sourceforge.net now has a pretty picture of a simple recursive transformation of 4 circles on the unit sphere (...thanks to __iter__ the ability to recursively transform any arbitrary set of geometric objects is now built-in to PyGeo). My current exploration (current as in today) is finding the mechanism to build a Mobius transformation that would be based (in part) on it's (pickable and movable) fixed points - of which a Mobius transformation has 2, which may coincide, or be located inconveniently - e.g. at infinity. Which has me stepping into the math of the fixed points of a function - it being trivial to find the fixed points, given the Mobius transformation matrix, but less trivial (from where I am sitting at the moment) to build the transformation from fixed point information. So I am struggling and researching some. In the course of which I come across this definition of "Fixed Point" in a programming glossary, @ http://carbon.cudenver.edu/~hgreenbe/glossary/second.php?page=F.html Of a function, f:X-->X, f(x)=x. Of a point-to-set map, F:X-->2^X, x is in F(x). The study of fixed points has been at the foundation of algorithms <http://carbon.cudenver.edu/%7Ehgreenbe/glossary/second.php?page=A.html#Algo…>. Having discussed here my growing interest in some study of algorithmics, but not getting there yet, but pursuing something that as far as I am aware is unconnected to such study, and then finding this statement indicating there is more of a connection - perhaps - than I had understood, is to me interesting. I have thought of "fixed point" (in programming) as connected to/opposed to "floating point", not as something directly connected to the concept of "f(x)=x" The statement above seems to be telling me otherwise. Guess I am fishing for some exposition on the statement that the "The study of fixed points has been at the foundation of algorithms" Art

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Recap of today's Python class (Urner @ Winterhaven)
by kirby urner 14 Dec '05

14 Dec '05

Today was my 4th session in a sequence of nine. I think the way it's developing for me is I hand out worksheets, which pose questions around Python, and students have the option to just fill them in, knowing Python "in their heads" well enough to not consult the actual interpreter. Others run the questions through Python. Others do a little of both. Worked pretty well today. The kids seemed very engaged. I walked around helping and explaining. We were in learning mode, not "prove to me you already know it" mode. We started out with an xmlrpclib demo. My setup was lame: Ethernet from my laptop to a neighboring PC, with an air gap to the actual PPS intranet. So of course it didn't work. Even after fixing the link, I was having problems. But some of the kids got their examples to work. In a way that was good: teacher in a group with floundering students, other students having it work. Very democratic. At the very end of the class, I retold the story about the young Gauss, this time suggesting he did the whole thing in his head. Like, the teacher said add 1 to 100 and he said hmmmm, that's range(1,101) and range(100, 0, -1) on top of each other, and a sum of 101, 101, 101... 100 times = 100(101). But that's twice the sum you need, so voila, 5050, in like 8 seconds. Stunned teacher. I explained why such consecutive sums-from-1 are considered "triangular" and threw out this challenge: class is about to end, but if anyone thinks they can do this: def tri(n): # something goes here return answer then let me know now. Type type type. A hand goes up. I quickly memorize the student's solution and transfer it to the screen up front (laptop -> projector -> screen): def tri(n): num = n * (n + 1) num = num / 2 return num (actually the student said 'print num' and I said that'd be OK too). And yes, tri(100) returns 5050, so big win. The kids felt one of their own had risen to the challenge, not in a competitive way, but as their representative. A peer had passed a tough test on their behalf. Note: using "__past__ style" division is OK in this context, as n, n+1 must form an even/odd pair, meaning their product is even, meaning 2 divides with no remainder (i.e. integer division OK). Kirby

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Urner @ Qwest: posts to edu-sig blocked
by kirby urner 14 Dec '05

14 Dec '05

Maybe a tightening spam filter is to blame. In any case, I'm resubscribing from my Gmail account. As a Qwest user, I'm used to being discriminated against, thanks to the activities of my fellow Qwestians. My next post will be back to business. Kirby ==== Hi. This is the qmail-send program at mpls-qmqp-01.inet.qwest.net. I'm afraid I wasn't able to deliver your message to the following addresses. This is a permanent error; I've given up. Sorry it didn't work out. <edu-sig(a)python.org>: 194.109.207.14 does not like recipient. Remote host said: 554 Service unavailable; Client host [63.231.195.112] blocked using t1.dnsbl.net.au; see http://dnsbl.net.au/rmst/ and http://dnsbl.net.au/lookup/?63.231.195.112 Giving up on 194.109.207.14. --- Below this line is a copy of the message.

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