Mailman 3 January 2014 - Edu-sig

a short essay about programming
by kirby urner 08 Dec '22

08 Dec '22

A common "error" (not too serious) that I see in beginning Python (and no doubt other languages, but Python is the one I'm teaching), is having a while condition that appears to put a lid on things, but then the flow all leaks away through break statements, such that the "front door" condition is never revisited. while guess != secret: guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") break else: print("Nope, try again...") What's messed up about the above code is you never really go back to the top in the case where you'd get to leave. Rather, you exit by the back door, through break. So in that case, wouldn't have been simpler and more elegant, even more "correct" (dare I say it) to have gone: while True: # no ifs ands or buts guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") break else: print("Nope, try again...") I see lots of heads nodding, and that could be the end of the matter, but then a next question arises: wouldn't this also be a more correct solution?: while guess != secret: guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") continue # instead of break else: print("Nope, try again...") We're back to having a variable while condition, not a boolean constant, but this time we actually exit by means of it, thanks to continue or... while guess != secret: guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") else: print("Nope, try again...") ... thanks to no continue. This last one is getting a thumbs up, but then I'd pause here and say "continue" can be easier on the eyes. It's unambiguous where it takes you, in contrast to having to scan on down the gauntlet, looking for possibly other open doors. "What happens next" should not require scanning ahead too far. Help us not to get lost. Be a civic-minded coder. I'm thinking of a programming style that advises two things: (a) if you use a while condition that's variable, that's expected to change, then your goal should be to always exit because of that, i.e. that should be your only exit point. Even if some other criterion suggests exiting, you have the option to flip that "lid" at the top, to crack that front door, and bounce the ball out. (b) which is why 'continue' is your friend. You are showing the user where your 'break' statements are, except you don't use "break" statements, as you've given a non-constant condition, and your aim is to make that your ONLY exit point. In short: never use break to exit a while loop unless your condition is while True. Instead, always flip the condition and exit through the font door. However, as soon as I make that rule I can think of good reasons to break it. The other programmers in the room are shaking their heads. Won't we lose information, needed elsewhere in the program, if we "artificially" force a True condition to False. Aren't we, in effect, lying? That concern could be addressed. Keep all the info true, just treat the "lid condition" (it "keeps a lid on it") as a flag. Go ahead and remember the user's guess. allowed = 5 tries = 1 exit = False while not exit: # no other way out guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") exit = True # instead of break continue print("Nope, try again...") tries += 1 if tries == allowed: print("You've maxed out") exit = True continue I think we all understand the main issue: writing reader-friendly code, and rules for doing so. There's something comforting about approaching a while loop and knowing its not a leaky sieve, riddled with back doors, maybe even an exit( ) time bomb. But in the recursion world we want a minimum of two exits usually: when another round is called for versus when we've "hit bottom". Can we have it both ways? Conclusions: Lets not be too hasty with rules of thumb and: Lets keep the reader in mind when writing code. Just because the interpreter knows to compute the flow unambiguously, doesn't mean all ways of writing it are equally reader-friendly. What may seem a gratuitous gesture, an unnecessary flourish, may actually promote reader comprehension of your code, and that should be a goal as much as satisfying the interpreter. Kirby

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Re: [Edu-sig] RurPLE-NG is nice
by Jurgis Pralgauskis 05 Apr '14

05 Apr '14

Some updates: - separated Variables Watch and Output panes, to be seen simultaneusly - implemented Breakpoints :) - beta style Todo: - let enter arbitrary watch expressions http://ftp.akl.lt/users/jurgis/python/rurple-NG053.png http://ftp.akl.lt/users/jurgis/python/rurple-ng-dz0-SplitLogVars_and_Breakp… for windows one doesn't need to install python separately, just unzip and run :) http://ftp.akl.lt/users/jurgis/python/RURPLE-NG-0.53%20%5bindependent%20exe… ps.: RurPLE-NG uses py3 unicode_literals, with_statement, division, print_function so code is generally py3 compliant. when wxpy will work well with py3 it shouldn't be too hard to port fully... >> >> just wanted to mention, >> that http://dev.lshift.net/paul/rurple/ >> is a very nice and lightweit PLE. >> >> what I like most (compared to RurPLE) are: >> 1) variables watch list (if it had breakpoints, it would rock :)

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Easy Web Environment to post pupils Python Creations
by Philip Bagge 01 Apr '14

01 Apr '14

Dear Colleagues, My Y6 pupils (10-11 year olds) have been creating some simple text based linear adventures using Python. Does anyone know of a way we can play their adventures online? They are not very complicated. You can see the planning here. https://sites.google.com/site/pythoncodecouk/python-adventure Also as a new person to your forum does anyone know of an easy way to search you archives just in case someone has already answered this question. Thanks in advance for any help Phil Bagge -- Primary ICT Advanced Skills Teacher HCC Teacher & IT Manager http://code-it.co.uk

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Re: [Edu-sig] Edu-sig Digest, Vol 126, Issue 3
by Murat Jumashev 30 Jan '14

30 Jan '14

How about Micro Python<https://www.kickstarter.com/projects/214379695/micro-python-python-for-micr…>? Is it too early to start teaching python using it? -------------------- Best regards / Урматым менен / С уважением, Murat Jumashev / Мурат Жумашев 2014-01-30 <edu-sig-request(a)python.org>: > Send Edu-sig mailing list submissions to > edu-sig(a)python.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://mail.python.org/mailman/listinfo/edu-sig > or, via email, send a message with subject or body 'help' to > edu-sig-request(a)python.org > > You can reach the person managing the list at > edu-sig-owner(a)python.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Edu-sig digest..." > > > Today's Topics: > > 1. Re: Python Lib for AR Drone 2.0 (A. Jorge Garcia) > 2. Re: Python Lib for AR Drone 2.0 (Nicholas H.Tollervey) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Wed, 29 Jan 2014 21:08:02 -0500 (EST) > From: "A. Jorge Garcia" <calcpage(a)aol.com> > To: fmasanori(a)gmail.com, edu-sig(a)python.org > Subject: Re: [Edu-sig] Python Lib for AR Drone 2.0 > Message-ID: <8D0EB773D94EFC0-13D8-2E1C0(a)webmail-m127.sysops.aol.com> > Content-Type: text/plain; charset="us-ascii"; format=flowed > > I'd love to know the answer too! > > I think that using a quadrotor in AP Computer Science class would be a > great motivator. I think the site you linked to is geared toward Linux > and uses PyGame or Processing. > > My classroom is Linux based, but I teach Java. I suppose an intro unit > with Python would be fine - or even a final project after the AP exam. > > I haven't used any quads in class yet, I've just been researching this > on the web of late. > > Sincerely, > A. Jorge Garcia > Applied Math, Physics & CS > http://shadowfaxrant.blogspot.com > http://www.youtube.com/calcpage2009 > 2013 NYS Secondary Math http://PAEMST.org Nominee > > > > > ------------------------------ > > Message: 2 > Date: Thu, 30 Jan 2014 09:11:12 +0000 > From: "Nicholas H.Tollervey" <ntoll(a)ntoll.org> > To: edu-sig(a)python.org > Subject: Re: [Edu-sig] Python Lib for AR Drone 2.0 > Message-ID: <52EA1730.6040507(a)ntoll.org> > Content-Type: text/plain; charset=ISO-8859-1 > > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On 30/01/14 02:08, A. Jorge Garcia wrote: > > I'd love to know the answer too! > > > > I think that using a quadrotor in AP Computer Science class would > > be a great motivator. I think the site you linked to is geared > > toward Linux and uses PyGame or Processing. > > > > My classroom is Linux based, but I teach Java. I suppose an intro > > unit with Python would be fine - or even a final project after the > > AP exam. > > > > I haven't used any quads in class yet, I've just been researching > > this on the web of late. > > > > Sincerely, A. Jorge Garcia Applied Math, Physics & CS > > http://shadowfaxrant.blogspot.com > > http://www.youtube.com/calcpage2009 2013 NYS Secondary Math > > http://PAEMST.org Nominee > > > > > > _______________________________________________ Edu-sig mailing > > list Edu-sig(a)python.org > > https://mail.python.org/mailman/listinfo/edu-sig > > You might be interested in this: > > http://ntoll.org/article/pyconuk2013-roundup > > Which contains videos of some of the Quadcopter fun we had at PyconUK > and their use within a real classroom environment (Ben Smith's video). > > N. > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.12 (GNU/Linux) > Comment: Using GnuPG with Icedove - http://www.enigmail.net/ > > iQEcBAEBAgAGBQJS6hcsAAoJEP0qBPaYQbb6IUoIALUZcun6TmPprhG3etuCjuR8 > zXByZ3PaKTv/6arczcaGS+9/GKNU5gapiZklLSwN/i9Nibj4JnraOQ/IjeX4+EJ4 > EQQThEbsW0gBP0ttTUJwFNNjoFnRuKfPE5Tsre82izexXmuuE7rs+CwstvumLfqi > E9hp1szH+I4Uh9eaWj5wT5vpyNVdA6dlPXvAGUAVGrJh4EuhPWnybr7ELAnVYQLx > ug131x3Mn4sEIX3S3UZ7Ne8dJrk2xHj/3/oLaIYYU6jz/T+eKkPAZv8xkR9W+BD+ > i8P9xUI2HdqeW5JO7DtYqEejprF1QfsfOEt58gIjhNMFWrdvUpfmbMagayhlYpo= > =OFbH > -----END PGP SIGNATURE----- > > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > Edu-sig mailing list > Edu-sig(a)python.org > https://mail.python.org/mailman/listinfo/edu-sig > > > ------------------------------ > > End of Edu-sig Digest, Vol 126, Issue 3 > *************************************** >

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Python for AR.Drone
by Lambert, Kenneth 30 Jan '14

30 Jan '14

>From my colleague, Simon Levy: http://home.wlu.edu/~levys/software/ardrone_autopylot/ Works with AR.Drone 1.0 and 2.0. No learning curve -- you just modify a single, already-written Python function. Only hitch is you need to be running Ubuntu. If you have a Mac, you can just use VMWare ($50) or VirtualBox (free) and install Ubuntu on top of that.

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Python Lib for AR Drone 2.0
by Fernando Masanori Ashikaga 30 Jan '14

30 Jan '14

Someone know a Python Lib for AR Drone 2.0? I use Python 2.7 or Python 3.3 and Debian or Windows 7 as Operating System. I have some trouble with https://github.com/venthur/python-ardrone

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CfP: 4th IEEE Track on Collaborative Modeling and Simulation (Comets 2014) - WETICE 2014
by Daniele Gianni 12 Jan '14

12 Jan '14

(Please accept our apologies if you receive multiple copies of this message) ################################################################# IEEE WETICE 2014 4th IEEE Track on Collaborative Modeling and Simulation (Comets 2014) in cooperation with INCOSE Italia (to be confirmed) MIMOS (Italian Association for M&S) CALL FOR PAPERS ################################################################# June 23-25, 2014, Parma (Italy) http://www.sel.uniroma2.it/comets14 ################################################################# # Papers Due: March 7, 2014 # Accepted papers will be published in the conference proceedings # by the IEEE Computer Society Press and indexed by EI. ################################################################# Modeling and Simulation (M&S) is increasingly becoming a central activity in the design of new systems and in the analysis of existing systems because it enables designers and researchers to investigate systems behavior through virtual representations. For this reason, M&S is gaining a primary role in many industrial and research fields, such as space, critical infrastructures, manufacturing, emergency management, biomedical systems and sustainable future. However, as the complexity of the investigated systems increases and the types of investigations widens, the cost of M&S activities increases for the more complex models and for the communications among a wider number and variety of M&S stakeholders (e.g., sub-domain experts, simulator users, simulator engineers, and final system users). To address the increasing costs of M&S activities, collaborative technologies must be introduced to support these activities by fostering the sharing and reuse of models, by facilitating the communications among M&S stakeholders, and more generally by integrating processes, tools and platforms. Aside from seeking applications of collaborative technologies to M&S activities, the track seeks innovative contributions that deal with the application of M&S practices in the field of collaborative engineering platforms. These platforms are continuously becoming more complex, and therefore their design requires systematic approaches to meet the required quality of collaboration. This is important for two reasons: to reduce rework activities on the actual collaborative environment, and to maximize the productivity and the quality of the process the collaborative environment supports. M&S offers the methodologies and tools for such investigations and therefore it can be used to improve the quality of collaborative environments. A non-exhaustive list of topics of interest includes: * collaborative requirements modeling * collaborative environments for M&S * collaborative Systems of Systems M&S * business proces modeling for collaborative environments * agent-based M&S * collaborative distributed simulation * collaborative component-based M&S * net-centric M&S * web-based M&S * model sharing and reuse * model building and evaluation * modeling and simulation of business processes * modeling for collaboration * simulation-based performance analysis of collaborative engineering platforms * model-driven approaches for collaborative engineering * domain specific languages for collaborative M&S * databases and repositories for M&S * distributed virtual environments * virtual research environment for M&S * collaborative DEVS M&S * multi-method M&S To stimulate creativity, however, the track maintains a wider scope and invites interested researchers to present contributions that offer original perspectives on collaboration and M&S. +++++++++++++++++++++++++++++++++++ On-Line Submissions and Publication +++++++++++++++++++++++++++++++++++ CoMetS'14 intends to bring together researchers and practitioners to discuss key issues, approaches, open problems, innovative applications and trends in the track research area. This year, we will accept submissions in two forms: (1) papers (2) poster and industrial presentations (1) Papers should contain original contributions not published or submitted elsewhere. Papers up to six pages (including figures, tables and references) can be submitted. Papers should follow the IEEE format, which is single spaced, two columns, 10 pt Times/Roman font. All submissions should be electronic (in PDF) and will be peer-reviewed by at least three program committee members. Accepted full papers will be included in the proceedings and published by the IEEE Computer Society Press (IEEE approval pending). Please note that at least one author for each accepted paper should register to attend WETICE 2014 (http://www.wetice.org) to have the paper published in the proceedings. (2) Posters should describe a practical, on-the-field, experience in any domain area using collaborative M&S. The poster submission requires the submission of an abstract for evaluation from the organizers. Accepted abstract must be followed by the submission of a poster which will be displayed at conference time. With the poster submission, a short (15 minutes) slot might be allocated for oral presentation illustrating the industrial case. The presentation may also include a live demo, but it should not include commercial details. Interested authors and participants may contact the organizers for expression of interests and content appropriateness at any time. Papers and posters can be submitted in PDF format at the conference submission site (https://www.easychair.org/conferences/?conf=wetice2014), by selecting the CoMetS track. Please feel free to contact the track chairs (dambro(a)uniroma2.it, danielegmail-comets(a)yahoo.it) if you experience problems with the EasyChair Web site. +++++++++++++++ Important Dates +++++++++++++++ * Submission Deadline: March 7, 2014 * Notification to authors: March 28, 2014 * Camera Ready to IEEE: April 11, 2014 * Conference date: June 23 - June 24, 2014 +++++++++++++++++ Program co-chairs +++++++++++++++++ Andrea D'Ambrogio, University of Roma TorVergata, Italy Daniele Gianni, Guglielmo Marconi University, Italy Joachim Fuchs, European Space Agency, The Netherlands Giuseppe Iazeolla, Guglielmo Marconi University, Italy +++++++++++++++++ Program Committee +++++++++++++++++ Paolo Bocciarelli, University of Roma TorVergata, Italy Alain Kerbrat, CollESys - AFIS, France Cristiano Leorato, Rhea, The Netherlands Steve McKeever, Uppsala University, Sweden David Nickerson, Auckland Bioengineering Institute, NZ Wolfgang Prinz, Fraunhofer FIT and RWTH Aachen, Germany José L. Risco-Martin, Universidad Complutense de Madrid, Spain Volker Schaus, DLR, Germany Sara Tucci, CEA/List, France Gabriel Wainer, Carleton University, Canada Quirien Wijnand, European Space Agency, The Netherlands Justyna Zander, Harvard University, USA, and Fraunhofer Institute FOKUS, Germany Gregory Zacharewicz, University of Bordeaux, France Heming Zhang, Tsinghua University, China *** Contact Information *** Andrea D'Ambrogio (track co-chair) Email: dambro(a)uniroma2.it

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