Mailman 3 August 2002 - Edu-sig

Python for Algorithms and Data Structures...
by Laurent Pierron Aug. 23, 2002

Aug. 23, 2002

Hi there... I'm trying to convince my colleague teachers to teach the science of computer programming with Python. It's not a problem to teach very basic computer programming with Python, but the major concurrent is VisualBasic which is more sexy with the graphic studio. For my colleagues now teaching basic computer programming is point-and-click to draw a nice interface and add some magic sentences to enforce the computer to do something, it's a non-sense and give a bad idea to the difficulty to think like a computer scientist. To teach "serious" computer programming (algorithm and data structure) there is some problems using Python, in France the course of algorithmic contains a large part about pointers (no pointers in Python), about Pascal-like record and data types, it's independant of the language but very Pascal-oriented. It's not dfficult to teach Pascal-like record with empty classes. Data types is just a matter of convention. But how to introduce pointer with Python, pointer is very important in computer science because it's very used in C and C++, and C/C++ are very used in computer science ? -- Laurent PIERRON -*- mailto:Laurent.Pierron@loria.fr Ingénieur de développement Service SeDre : http://www.loria.fr/LORIA/EXT/services/SEDRE/ INRIA-Lorraine / LORIA -*- bureau : B 042 615, rue du Jardin Botanique -*- mobile/SMS : +33 6 72 23 03 80 B.P. 101 -*- voix : +33 3 83 59 30 93 54602 Villers les Nancy (France) -*- fax : +33 3 83 27 83 19

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RE: [Edu-sig] Python for Algorithms and Data Structures...
by Seabrook, Richard Aug. 23, 2002

Aug. 23, 2002

I think both views have merit. On one hand, pointers aren't essential for any particular algorithm, they are a subject in and of themselves requiring considerable exposure and experimentation to grasp. On the other, languages that do not have pointers invariably get into some explanation difficulties sooner or later. For example, in Python some copying and assignment operations result in two names referring to the same object, rather than two unique objects. In languages with pointers this is much easier to explain, once students grasp the idea of a pointer. Dick S. -----Original Message----- From: Markus Gritsch To: Laurent Pierron; edu-sig(a)python.org Sent: 8/23/02 6:18 AM Subject: Re: [Edu-sig] Python for Algorithms and Data Structures... Laurent Pierron wrote: > Hi there... > > It's not dfficult to teach Pascal-like record with empty classes. > Data types is just a matter of convention. > But how to introduce pointer with Python, pointer is very important in > computer science because it's very used in C and C++, and C/C++ are very > used in computer science ? In my opinion: Pointers are not necessary. They are only an artefact of C which you have to know and to use to write useful code. C++ introduces references and actually Python also uses references. Python combines this with mutual and non-mutual data types which is IMHO quite elegant. The separation of algorithm and data-types is done in C because C has no method for including algorithms into data-types, i.e. Classes. Therefore generating this artificially in Python by struct-like Classes seems not optimal to me. To decouple algorithms and data-types when really needed, C++ introduced templates. This is only necessary because of the static typing of C++ variables. Python has dynamic typing, so there is no need for templates there. Polymorphism is also a strong technique, but just not supported by C. My 2c, Markus _______________________________________________ Edu-sig mailing list Edu-sig(a)python.org http://mail.python.org/mailman/listinfo/edu-sig

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Role Reversal...
by Peter H. Froehlich Aug. 22, 2002

Aug. 22, 2002

Hi! I read the "teaching by role reversal" discussion, and while I like the general idea, I have to admit (maybe I am getting too old) that it sounds like quite a risky project. In my experience, many (most?) students are just not interested, all they need is a grade. The five exceptions to the rule per quarter make teaching fun. That might be a function of the US system, but I have the weird feeling that most of my class would stare at me blankly when I say "Okay, so those are the basics of hash tables. Now give me some problems regarding the data structure that I can solve for you." or something. On the other hand, maybe I am not getting the approach described correctly, or maybe I would even be surprised by the response once I do it in class. I think I will give it a whirl once or twice during the coming quarter, just to see what happens. Peter -- Peter H. Froehlich []->[!]<-[] http://nil.ics.uci.edu/~phf/ OpenPGP: D465 CBDD D9D2 0D77 C5AF 353E C86C 2AD9 A6E2 309E

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Re: [Edu-sig] BBC NEWS UK Education GCSE 'gender gap' sparksconcern
by Jason Cunliffe Aug. 22, 2002

Aug. 22, 2002

One of the thing which made me laugh/wince is how even the response is framed in largely negativ/competitive terms. Instead of celebrating that the girls are doing _well_, it's like ohno we have only a problem. Did you see the comment that the boys are all watching too much soccer [football] on TV? Not to mention all that cheap dutch Ecstacy they take on weekends >:-! The higher percentage of boys still in "IT", also provokes the question of what kind of teaching they are really getting and what should/could be done about it. It would be intersting to know what the figures are for all of Europe this summer... hell for the whole planet. That *would* be interesting. Does anyone know how many teenagers in the world are exposed to Python and where? I've been semi-watching the Annenburg/CPB on late night Channel 25 for the past 10 days. The mechanical universe, Mitch Resnick on computational literacy with 'crickets' and Lego Mindstorms. One series focused on early numeracy and problem solving. It had the teacher first put problems to the kids. Then the reverse. Wow they really woke up. You could see their brains going into a different gear. It made me think that that's a large part of what programming and especially with a CLI-based system like Python is sort of like. when the kids were 'designing' prblems for teh teacher, she became the computer system and they in their clusters became little alogothimic scripts. Fascinating ./Jason

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BBC NEWS UK Education GCSE 'gender gap' sparksconcern
by Arthur Aug. 22, 2002

Aug. 22, 2002

Jason asks: >The higher percentage of boys still in "IT", also provokes >the question of what >kind of teaching they are really getting and what >should/could be done about it. Perhaps folks are making free choices, at levels of complexity we can not hope (nor should particularly care) to understand, and what should be done about it is nothing. Now if there is evidence that a women who chooses to make best efforts at a carreer in programming is inhibited in *any* way as a result of her gender - that is a totally different issue - and one which is worth a fight. But it seems that even if that fight is declared won, there are those who seem committed to needing something on their todo list connected to all this. Art

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Re: [Edu-sig] BBC NEWS UK Education GCSE 'gender gap' sparksconcern
by Jason Cunliffe Aug. 22, 2002

Aug. 22, 2002

> Are we being off topic again? I've had my wrists slapped twice already > although several people seemed interested. Maybe I misunderstand the way > the list is run? I hope not. Life+learning mean little or nothing without context.. ./Jason

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BBC NEWS UK Education GCSE 'gender gap' sparks concern
by Jason Cunliffe Aug. 22, 2002

Aug. 22, 2002

http://news.bbc.co.uk/2/hi/uk_news/education/2208547.stm

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Use? Abuse? Amusement? Amendments?
by Gregor Lingl Aug. 22, 2002

Aug. 22, 2002

Hi! If you, incidentally, are going to have a coffee-break, please, run the code of the attachment. Your opinion? Gregor from __future__ import generators from turtle import * def ttree(t,l): if l > 12.0: t.forward(l) yield 1 t.left(25) for x in ttree(t, l * 0.65 ): yield x t.right(60) yield 1 for x in ttree(t, l * 0.52 ): yield x t.left(35) t.backward(l) yield 1 turtles = (leonardo, raphael, donatello) = (Pen(), Pen(), Pen()) for turtle in turtles: turtle.left(90) turtle.up() leonardo.goto(-100,-100) leonardo.color("red") raphael.goto( 0, -100) raphael.color("green") donatello.goto(100,-100) donatello.color("orange") for turtle in turtles: turtle.down() turtle.width(3) ltree = ttree(leonardo,79.0) rtree = ttree(raphael, 100.0) dtree = ttree(donatello, 66.0) done = 0 while done < 3: done = 0 for tree in (ltree, rtree, dtree): try: tree.next() except: done += 1 leonardo.up() leonardo.goto(-140,-135) leonardo.write("HOW CAN THIS BE DONE WITHOUT GENERATORS?") raw_input("Press Enter!")

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Python for Algorithms and Data Structures...
by Peter H. Froehlich Aug. 21, 2002

Aug. 21, 2002

Hi there, I am about to teach an introductory course (read: third course in the intro sequence, university level) on algorithms and data structures. I am looking for experiences in teaching such a course using Python. I have used Python successfully last summer for a compiler course, but since the "default" language for this course is supposed to be C++ I have a harder time balancing between the student's previous experience and my desire for a clean presentation (using Python as "pseudo code" of a sort). What this all comes down to: If you have used Python in any capacity for a similar course, please let me know about it. :-) Peter -- Peter H. Froehlich []->[!]<-[] http://nil.ics.uci.edu/~phf/ OpenPGP: D465 CBDD D9D2 0D77 C5AF 353E C86C 2AD9 A6E2 309E

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re: Does edu-sig extend to Jython
by Arthur Aug. 21, 2002

Aug. 21, 2002

Kirby writes - >Whatever the solution, it shouldn't add the overhead of slower >speed. As a user, I don't want a programmer bending over >backwards to accommodate my ignorance of programming, at the >price of giving me slow-moving bloatware ala some Microsoft >products. Agreed. I'm figuring that whatever I do in the initialization routines will manifest itself, in the worst case, as a second or two at start-up. The update cycles - where the performance does really count - needs to be quite free of this kind of isinstance, or switch/case, or whatever. >Why would you feel different about your user if it were a Java >app? Don't you want the same freedoms to pass parameters in >any order, no matter what the language? Just curious. I tried to make that clear, and think it goes to the bottom of why I feel confident that I am in the right place with Python for what I am trying to do. To me "immediate mode" with dynamic typing versus compile cycle with static typing should be recognized as two very different experiences, with very different needs. I guess I consider myself as to be trying to build an SUI - script users interface. There are very specific and compelling (to me) reasons that I don't want to go too far toward either the GUI side, or the API side. Art

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