Mailman 3 October 2012 - 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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LearnStreet's Free Online Python Course
by Aakash Prasad 18 Nov '12

18 Nov '12

Hi all, I'd like to tell you about a free online Python course that my startup, LearnStreet (http://www.learnstreet.com), has recently launched (along with courses on JavaScript and Ruby). Our courses are designed for beginners and are fun, engaging and interactive through the use of multiple learning modalities. How is LearnStreet different from other learn-to-code sites you ask? UI/UX: A key aspect of LearnStreet’s courses is its distinct UI/UX. In order to see this, start any one of our courses. Multi-modal: Our courses are designed for beginners, and we have multiple ways to help them learn, including live chat, Twitter, Q&A, hints, videos and background material. http://www.learnstreet.com/lessons/languages/python Code Garage: Like many of you here, if you already know how to code, check out Code Garage where you can try your hand at cool coding projects like building a Mastermind game or a Sudoku Solver. http://www.learnstreet.com/cg/simple/projects/javascript Dev Tools: We’ve culled the web to provide some key resources beyond the core programming language that will help beginners gain a better understanding of what it takes to become a competent coder. http://www.learnstreet.com/dev_tools/ We just launched about a couple of weeks ago and would love to get your thoughts and feedback. We are looking for expert coders to help build out our other courses so check out the Contribute section on our site as well. Thanks Aakash

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*** Extended Deadline *** Nov 19 CfP: 3rd International Workshop on Model-driven Approaches for Simulation Engineering (Mod4Sim13) part of the Symposium on Theory of Modeling and Simulation SCS SpringSim 2013)
by Daniele Gianni 31 Oct '12

31 Oct '12

(Please accept our apologies if you receive multiple copies of this CFP) ################################################################# CALL FOR PAPERS 3rd International Workshop on Model-driven Approaches for Simulation Engineering part of the Symposium on Theory of Modeling and Simulation (SCS SpringSim 2013) in technical cooperation with INCOSE San Diego Chapter ################################################################# April 7-10, 2013, San Diego, CA (USA) http://www.sel.uniroma2.it/Mod4Sim13 ################################################################# # Papers Due: *** November 19, 2012 *** Extended ***** # Accepted papers will be published in the conference proceedings # and archived in the ACM Digital Library. ################################################################# The workshop aims to bring together experts in model-based, model-driven and software engineering with experts in simulation methods and simulation practitioners, with the objective to advance the state of the art in model-driven simulation engineering. Model-driven engineering approaches provide considerable advantages to software systems engineering activities through the provision of consistent and coherent models at different abstraction levels. As these models are in a machine readable form, model-driven engineering approaches can also support the exploitation of computing capabilities for model reuse, programming code generation, and model checking, for example. The definition of a simulation model, its software implementation and its execution platform form what is known as simulation engineering. As simulation systems are mainly based on software, these systems can similarly benefit from model-driven approaches to support automatic software generation, enhance software quality, and reduce costs, development effort and time-to-market. Similarly to systems and software engineering, simulation engineering can exploit the capabilities of model-driven approaches by increasing the abstraction level in simulation model specifications and by automating the derivation of simulator code. Further advantages can be gained by using modeling languages, such as UML and SysML – but not exclusively those. For example, modeling languages can be used for descriptive modeling (to describe the system to be simulated), for analytical modeling (to specify analytically the simulation of the same system), and for implementation modeling (to define the respective simulator). A partial list of topics of interest includes: * model-driven simulation engineering processes * requirements modeling for simulation * domain specific languages for modeling and simulation * model transformations for simulation model building * model transformations for simulation model implementation * model-driven engineering of distributed simulation systems * relationship between metamodeling standards (e.g., MOF, Ecore) and distributed simulation standards (e.g., HLA, DIS) * metamodels for simulation reuse and interoperability * model-driven technologies for different simulation paradigms (discrete event simulation, multi-agent simulation, sketch-based * simulation, etc.) * model-driven methods and tools for performance engineering of simulation systems * simulation tools for model-driven software performance engineering * model-driven technologies for simulation verification and validation * model-driven technologies for data collection and analysis * model-driven technologies for simulation visualization * Executable UML * Executable Architectures * SysML / Modelica integration * Simulation Model Portability and reuse * model-based systems verification and validation * simulation for model-based systems engineering To stimulate creativity, however, the workshop maintains a wider scope and welcomes contributions offering original perspectives on model-driven engineering of simulation systems. +++++++++++++++++++++++++++++++++++ On-Line Submissions and Publication +++++++++++++++++++++++++++++++++++ We invite paper submissions in three forms: 1. Full paper (max 8 pages), describing innovative research results. These papers are eligible for the best paper award and may be invited for an extended version in a special issue of the SCS SIMULATION journal. 2. Work-in-progress paper (max 6 pages), describing novel research ideas and promising work that have not yet been fully evaluated. 3. Short paper (max 6 pages), describing industrial and hands-on experience on any relevant area (i.e. military, government, space, etc.). All the papers must be submitted through the SCS conference management systems (http://www.softconf.com/scs/DEVS13/) and select the Mod4Sim track. The submissions must be in PDF format and conform to the SCS conference template (Word template is available at http://www.scs.org/upload/documents/templates/ConferenceSubmissionWORDTempl… , guidelines are available at http://www.scs.org/PDFs/formattingkit.pdf). All the submitted papers must be original and not submitted else where. Submitted papers will be peer reviewed with respect to their quality, originality and relevance. The authors of the accepted papers must register in advance for inclusion of their paper in the conference proceedings. Authors of accepted papers will be invited to update their papers basing on the reviews, before providing the camera ready. All accepted papers will be included in the conference proceedings and archived in both the ACM Digital Library and IEEE Digital Library. Authors may contact the organizers for expression of interest and content appropriateness at any time. +++++++++++++++ Important Dates +++++++++++++++ * Submission Deadline: November 19, 2012 *** Extended *** * Decision to paper authors: January 10, 2013 * Camera ready due: February 5, 2013 * Conference dates: April 7-10, 2013 ++++++++++++++++++++ Organizing Committee ++++++++++++++++++++ * Andrea D'Ambrogio - University of Rome TorVergata, Italy * Daniele Gianni - European Space Agency, The Netherlands +++++++++++++++++ Program Committee +++++++++++++++++ * Steffen Becker - University of Paderborn, Germany * Paolo Bocciarelli - University of Rome TorVergata, Italy * David Chen - Univeristy of Bordeaux I, France * Cristian Englert - Serco, The Netherlands * Huascar Espinoza - European Software Institute and Tecnalia, Spain * Paul A. Fishwick - University of Florida, USA * Carlos Juiz - University of Balearic Islands, Spain * Cristiano Leorato - Rhea, The Netherlands * Steve McKeever - University of Oxford, UK * Halit Oguztüzün - Middle East Technical University, Turkey * Andreas Tolk - Old Dominion University, USA * Hans Vangheluwe - University of Antwerp, Belgium and McGill University, Canada * Anthony Walsh - European Space Agency, Germany * Heming Zhang - Tsinghua University, China *** Contact Information *** Andrea D'Ambrogio and Daniele Gianni (workshop co-chairs) Emails: dambro(a)uniroma2.it and danielegmail-mod4sim(a)yahoo.it

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python vs processing for introducing programming?
by Andy Judkis 31 Oct '12

31 Oct '12

Hello, I've been using Python for about 7 or 8 years now to introduce my 10th graders to programming, and I've been quite happy with it. We start out with a week of Scratch and a week of RUR-PLE (which I love) before moving on to about 3 weeks of Python. Obviously they don't become experts in that time frame, my goal is to just give them a taste of programming. I've tried various Python environments and graphics libraries over the years -- IDLE with livewires, IDLE with the cs1graphics package, JES, vpython -- and they all have their virtues and pitfalls, at least for my application. I've recently become aware of Processing and am really intrigued. Here are some advantages I see: * some fun lessons on khanacademy to get started (a processing library for javascript, actually) * very easy installation, nice simple IDE * graphical from day 1, very easy interaction with mouse * there's a great book on using processing with Kinect (Making Things See, from O'Reilly) and I think I can demo and talk about some cool stuff from that The obvious downsides to me are: * no RUR-PLE * overall, Processing just isn't as real-world useful as Python I'd be interested in hearing from anyone with experience in teaching Processing to this age group, and anyone with any thoughts on the topic. Thanks, Andy Judkis Academy of Allied Health and Science Neptune, NJ

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Re: [Edu-sig] "dot notation" (in favor of sharing it)
by Litvin 29 Oct '12

29 Oct '12

At 10:08 AM 10/26/2012, michel paul wrote: >Yesterday I was involved in a math education group at my school >where an example suggested for introducing 'function' was 'toast'. >Basically, you put bread into the toaster, and <magic/technology >happens> out comes toast! So 'toasting' is a function. Seems to make >sense, right? Then eating a piece of toast is an example of function composition? :) And what would be the inverse function? :) Gary

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"dot notation" (in favor of sharing it)
by kirby urner 26 Oct '12

26 Oct '12

http://mathforum.org/kb/thread.jspa?threadID=2407414 Interesting thread IMO. Kirby PS: also enjoying that Ada Day threads on Diversity (python.org)

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Computer Science Education Week (2012 Dec 9-13)
by wesley chun 18 Oct '12

18 Oct '12

folks who are doing events/activities for CSEd week should post them up to the main website (there's only 2 thus far). while i'm available to give a session (talk or codelab) for any events close to where i'm based (silicon valley), i don't have the bandwidth to organize an entire event. anyway, the standard pitch is given below. cheers, --wesley Computer Science Education Week <http://www.csedweek.org/> (December 9-13, 2012) is about celebrating and creating visibility for the importance of K-12 computer science education. Although the advocacy work is US-focused, the celebration includes events and activities from all around the world. Many teachers engage students in special CS-related activities during CSEdWeek itself, but CS-related activities take place all year long, and CSEdWeek strives to recognize and celebrate them all. To do this, we invite you to pledge support<http://www.csedweek.org/forms/sign/pledge-step1> for CSEdWeek and post CS-related K-12 activities on the CSEdWeek web site. The more events we show, the better equipped we'll be to make the case that CS education is vitally important and deserves local, national, and international support! Please note that contact information is input in Step 1 and in Step 2 you will be invited to add your event or other outreach activity. http://www.csedweek.org/forms/sign/pledge-step1 -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - "A computer never does what you want... only what you tell it." +wesley chun : wescpy at gmail : @wescpy Python training & consulting : http://CyberwebConsulting.com "Core Python" books : http://CorePython.com Python blog: http://wescpy.blogspot.com

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Columbus Python Workshop (and IPython Notebook)
by Catherine Devlin 16 Oct '12

16 Oct '12

Announcing the first Columbus Python Workshop for women and their friends! Jan. 18-19, 2013 The Columbus Python Workshop for women and their friends is a free hands-on introduction to computer programming that's fun, accessible, and practical even to those who've never programmed at all before. We empower women of all ages and backgrounds to learn programming in a beginner-friendly environment. Thanks to Pillar Technologies for hosting the workshop in their brand-new office in Columbus' Short North! The workshop is the latest in a series based on the famous Boston Python Workshop; they've already introduced hundreds of beginners to programming in Boston, Indianapolis, Portland, Chicago, and Kansas City. Now it's Ohio's turn, so spread the word! Get more details and sign up now: https://openhatch.org/wiki/Columbus_Python_Workshop * Happy Ada Lovelace Day! Traditionally, Ada Lovelace Day is celebrated by highlighting the achievements of present and past women in programming. Today, instead, I'm saluting the contributors of the future! * --- Two more aspects about this might be especially interesting to educators: 1) If you haven't looked into the Boston Python Workshop's curriculum, you really must... it's extremely thoughtful about ramping true beginners in gently and remembering all the instructions they need. 2) I'm planning to use the IPython Notebook in the workshop in what I hope will be a really amazing way. I've blogged about the beginning of this work at http://catherinedevlin.blogspot.com/2012/10/im-increasingly-amazed-at-ipyth…, but now I'm pretty confident that I can and will get the doctests to report their realtime results up to an instructor's dashboard as the student works. I'll post again here about that when it's ready. -- - Catherine http://catherinedevlin.blogspot.com

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PyconUK education track write-up
by Nicholas H.Tollervey 10 Oct '12

10 Oct '12

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi EduSIGers, Over the final weekend of September we held PyconUK 2012. I helped to organise the education track (as mentioned previously on this list) and I've finally found the time to write up what happened: http://ntoll.org/article/pyconuk2012 The education "sprint" was especially good fun as both teaching and developer colleagues collaborated on the beginnings of various resources. I hope you find it interesting and I'm happy to answer any questions you may have. Best wishes, Nicholas. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://www.enigmail.net/ iQEcBAEBAgAGBQJQdQ8CAAoJEP0qBPaYQbb66DQH/2ThbrOAnMQIm/U/LsCv4/4f OXeI2WIiV887TtU5c5EmpwcEN8jxdzXrF5Td3YzSv1K+k5jIFEfxfBjcLV+qcQDA sW+DSS0Y/SbMW+/N9PrnTAQZNETzpWAxw9TYYrNDOQakOfvzaBUsLgzbaqpAEe9n XOTOp3NxxTm73ib0+ALFlwZCAIS4SzXd7jD5b6fY+mbNRT9bZgbf1lSuXrOoS/Uz F9jN9IvtxT6JF485rH6DUwQTtKSJIiXTY1bDVbv4kGHaCqf9/Xezf6aNfexNz3Gv /300QnE6XqvjGLGnR1rvXSMlceKEwsrcP9mPu82/sjrkGfjiyIM6EdyaAqaeiFM= =H+sP -----END PGP SIGNATURE-----

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"Seven ways to use Python's new turtle module"
by Daniel Ajoy 09 Oct '12

09 Oct '12

"Seven ways to use Python's new turtle module", presented at PyCon 2009 http://lockerz.com/u/21205615/decalz/13082004/seven_ways_to_use_python_s_ne…

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