Re: [Edu-sig] Accessibility to non CS types?
On 5/26/06, kirby urner [EMAIL PROTECTED] wrote: So you're saying Python is sufficiently accessible because we may still assume scientists and engineers are learning C++ and Java? The fact remains:many academics are throwing up their hands when encountering Python, because they can't make the leap from what they knew before. If I may, I'd like to start with a brief personal history to introduce what I see as two barriers to learning Python for scientists/academics.I learned FORTRAN in 1977 in a College-level course (pre-University in Quebec). I then went to University to study Physics. During my undergraduate degree, I wrote perhaps 3 (short) computer programs. Still, FORTRAN was easily understood as the stuff I did was mostly numerical work. *The concepts and language I had learned in Physics were easily adaptable in FORTRAN.* While in graduate school, I bought a PC and learned some basic C programming, mostly for fun. Again, I didn't write many programs, and they weren't very long. It did prepare me for what was to come. *The transition from FORTRAN and C was fairly easy, as I could write FORTRAN-style programs in C ;-). As a Physics prof, I wanted to introduce visual tools to my students. After learning about Java Applets, I decided that they were an ideal tool. So, I set up to learn enough Java to write my own applets for physics demo. I wrote a grand total of perhaps 10 applets over the course of 3 years, in between teaching and doing research. This was around 1995. The first barrier I encountered was the dot notation. Nowhere did I see it explain separately, as a notational convention, shared by many languages. I thought it was something weird about Java that I would have to learn. Solution: introduce the dot notation totally separately from the other programming syntax. This is something I tried to do in one rur-ple lesson.The second barrier I found was the insistance on categorizing relationships in terms of is-a and has-a. The examples that I would find most natural to look at were often counterintuitive. I remember in particular seeing that programming examples that use the relationships between a circle and an ellipse (or a rectangle and a square) seemed to have the relationship going backwards. Let me give a concrete example explaining inheritance for non-computer scientists.===class Father(object): def __init__(self): self.eye_colour = blue def greets(self): print Hello there! class Mother(object): def __init__(self): self.eye_colour = brownclass Child(Mother, Father): passSally = Child() print Sally.eye_colourSally.greets()===The computer scientists in the (virtual) room are probably horrified. A Child is not a Mother, nor a Father and you do not have the proper is-a relationship. Yet, I would claim that the above example would be very appropriate for the average person. Sally inherit brown eyes for her mother, not because brown is the dominant gene (as in biology) in this case, but because of the inheritance order. (Interchange Mother and Father in the class Child and Sally will have blue eyes) Words like inheritance have been borrowed and adapted by computer scientists for use in their own discipline. They have been borrowed because they were familiar words that conveyed (partly) the concept used in the scientific discipline. They have been adapted because the usual definition was not technically correct. I believe that teaching those concepts should go through the same process: start with the familiar (but slightly incorrect) use of the word, and refine later on. This, btw, is how I use to teach about work in physics, so I have some idea about the possible use of this approach.. If I ask my son to carry the groceries bags from the car to the kitchen (essentially at the same horizontal level), he will not believe me if I tell him that he did no work. Yet, he would have done no work (W=0) [against gravity], as every physics textbook would tell you. ==As a final point about the personal history: after not having done any programming for about 8 years (and having never written any significant computer program), I decided to learn Python as a hobby with the goal to eventually teach my kids. By then, I had some idea about the dot notation, so this barrier was easily overcome. Python tutorials that I skimmed through did not insist on the importance of is-a and has-a relationship, so I didn't feel constrained in how I set up the relationships between the classes I wrote. I was free to explore (and make mistakes!) and it was fun! It still is. André ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
[Edu-sig] Elementary graphics library
As part of my Summer of Code proposal, I said i would write a simple graphics library. I've spent the last couple of hours brainstorming this, and written it all up: http://crunchy.python-hosting.com/wiki/GraphicsDoc. If anyone has any comments/ideas I would love to hear them! Johannes -- Johannes Woolard, Oriel College, Oxford OX1 4EW 07837880296 ox extn: 26611 ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
Re: [Edu-sig] Accessibility to non CS types?
On 5/28/06, Andre Roberge [EMAIL PROTECTED] wrote: The first barrier I encountered was the dot notation. Nowhere did I see it explain separately, as a notational convention, shared by many languages. I thought it was something weird about Java that I would have to learn. Solution: introduce the dot notation totally separately from the other programming syntax. This is something I tried to do in one rur-ple lesson. I very much agree. I even go so far as to phase dot notation into standard mathematics, as another way to express such concepts as mytriangle.A (returns a degree measure). Use dot notation even without reference to any specific computer language, but with reference to the OO paradigm (math as extensible type system meme). The second barrier I found was the insistance on categorizing relationships in terms of is-a and has-a. The examples that I would find most natural to look at were often counterintuitive. I remember in particular seeing that programming examples that use the relationships between a circle and an ellipse (or a rectangle and a square) seemed to have the relationship going backwards. Let me give a concrete example explaining inheritance for non-computer scientists. === class Father(object): def __init__(self): self.eye_colour = blue def greets(self): print Hello there! class Mother(object): def __init__(self): self.eye_colour = brown class Child(Mother, Father): pass Sally = Child() print Sally.eye_colour Sally.greets() === The computer scientists in the (virtual) room are probably horrified. A Child is not a Mother, nor a Father and you do not have the proper is-a relationship. Yet, I would claim that the above example would be very appropriate for the average person. Sally inherit brown eyes for her mother, not because brown is the dominant gene (as in biology) in this case, but because of the inheritance order. (Interchange Mother and Father in the class Child and Sally will have blue eyes) Words like inheritance have been borrowed and adapted by computer scientists for use in their own discipline. They have been borrowed because they were familiar words that conveyed (partly) the concept used in the scientific discipline. They have been adapted because the usual definition was not technically correct. I believe that teaching those concepts should go through the same process: start with the familiar (but slightly incorrect) use of the word, and refine later on. Yes. This is characteristic of many disciplines; they absorb from ordinary language, but pretty soon stop paying their debt, i.e. stop building on-ramps. Instead, they close off and fortify, so that those not in the know sound like fools to the ears of insiders. It's a kind of corruption really. My buddy Ed Applewhite had 'Layman' printed on his business card, kind of a warning that he was nobody's fool (yet he often pretended he couldn't quite follow). This, btw, is how I use to teach about work in physics, so I have some idea about the possible use of this approach.. If I ask my son to carry the groceries bags from the car to the kitchen (essentially at the same horizontal level), he will not believe me if I tell him that he did no work. Yet, he would have done no work (W=0) [against gravity], as every physics textbook would tell you. Yes, work is especially problematic, as it only counts if against the vectors you consider worthy. Irrelevant vectors, though resistent, don't bar the way to getting the job done (at least not directly), so you can go down fighting, working like crazy, yet the physicist will tell you you're doing no work whatsoever (like the burglar fumbling with the safe combo is doing no work, if the police come too soon). == As a final point about the personal history: after not having done any programming for about 8 years (and having never written any significant computer program), I decided to learn Python as a hobby with the goal to eventually teach my kids. By then, I had some idea about the dot notation, so this barrier was easily overcome. Python tutorials that I skimmed through did not insist on the importance of is-a and has-a relationship, so I didn't feel constrained in how I set up the relationships between the classes I wrote. I was free to explore (and make mistakes!) and it was fun! It still is. André Useful autobio. I used to strongly encourage Arthur to switch into this mode from time to time. That's related to your earlier remarks about academic jargons: we're each a walking namespace (Pythonic concept), yet sometimes forget that fact (fish unaware of water). When you go into autobio, people get a better idea of how to factor out various biases you may never be free of in this life (because they define you as a person e.g. fought in 'Nam for eight years). Your discussion of how is-a versus has-a easily confounds is quite useful. And I
Re: [Edu-sig] list newbie
Kris Olson wrote: I am new to teaching Python but have enjoyed the reaction of my students to Python. I have been using the interactive mode to demonstrate it is hard for them to see when I get down to the bottom of the page. Is there a way to clear the screen or open a new interactive screen? Here's a trick I use for myself when the shell screen gets too full: 1) Make sure another window is open (do File / New Window if needed). 2) Close the shell screen. 3) On (one of) the open window(s) do Windows / Python Shell. You now have a nice clean window. I agree it would be nice to be able to prune the shell window contents. Especially if you have output some long text w/o returns in it, scrolling can get painfully slow as the output accumulates. -- Scott David Daniels [EMAIL PROTECTED] ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
Re: [Edu-sig] Elementary graphics library
If you haven't already, you could check out: Pyxel http://bellsouthpwp.net/p/r/prochak/pyxel.html Pyxel is a python library that provides a dynamic, interactive, highly portable, graphical environment. It makes diagrams and widgets look identical in whatever underlying environment it supports. wxOGL http://wiki.wxpython.org/index.cgi/wxOGL The OGL library was originally written in C++ and provided to wxPython via an extension module wrapper as is most of the rest of wxPython. The code has now been ported to Python (with many thanks to Pierre Hjälm!) in order to make it be more easily maintainable and less likely to get rusty because nobody cares about the C++ lib any more. (bottom of that pages has more alternatives, like the next) Piddle http://piddle.sourceforge.net/ PIDDLE is a Python module for creating two-dimensional graphics in a manner that is both cross-platform and cross-media; that is, it can support screen graphics (e.g. QuickDraw, Windows, Tk) as well as file output (PostScript, PDF, GIF, etc.). It makes use of the native 2D drawing calls of each backend, for maximum efficiency and quality. It works by defining a base class (piddle.Canvas) with methods for all supported drawing primitives. A particular drawing context is provided in the form of a derived class. PIDDLE applications will be able to automatically select an appropriate backend for the user's environment. and of course PyGame or PySDL or even the OpenGL Canvas stuff (there are probably more) for ideas and to see what others have done before in pure Python and you could possibly build on. Or even PyGeo if your focus is mainly on geometry instead of arbitrary 2D graphics (I wasn't sure). There are a lot of charting and plotting and other graphics packages out there with Python bindings (including Cairo, which you are looking at as your first backend target). You can ask yourself if a newer API really gets you that much over these existing things? Will it really be that much simpler once you really try to make it useful? And if you have a crossplatform backend already like Cairo or wx, does it gain you that much to abstract above that if can you simplify it somehow, versus just make a simple interface to one cross-platform library (which may be hard enough)? Now, it still might be worth doing for you even if the answers are no, but to maximize your effectiveness it is nice go in with your eyes open about whether you are doing this to learn and to have fun, to improve an existing thing, or to make something new that fills an empty niche (or to try do do all three); that is a question I often wrestle with for my own projects. :-) --Paul Fernhout Johannes Woolard wrote: As part of my Summer of Code proposal, I said i would write a simple graphics library. I've spent the last couple of hours brainstorming this, and written it all up: http://crunchy.python-hosting.com/wiki/GraphicsDoc. If anyone has any comments/ideas I would love to hear them! Johannes ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
Re: [Edu-sig] list newbie
On 5/28/06, Scott David Daniels [EMAIL PROTECTED] wrote: Here's a trick I use for myself when the shell screen gets too full: 1) Make sure another window is open (do File / New Window if needed). 2) Close the shell screen. 3) On (one of) the open window(s) do Windows / Python Shell. You now have a nice clean window. But then you lose the session. You could recover the session by re-entering the necessary lines (e.g. importing modules, defining variables), but that leaves us with the original problem... -Steven Bird ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
Re: [Edu-sig] Accessibility to non CS types?
At 22:23 26/05/2006, Ian Bicking wrote: Not many scientists and engineers learn C or sh any more. ABC's developers had the right idea. Yes, but they learn C++ and Java and things like that. You wish. As part of my project I did a brief survey of what physics departments used to teach programming (research that didn't make it into the final report due to space). Most offered only an introductory course, often less than 1 lab a week for 10 weeks. C was still popular (as was Fortran) but I argue that due to the lack of time the scientists and engineers don't learn these languages, they learn enough to complete the exercises to finish the course. Not because they're inherantly lazy, but because there's way too much material to cover in the pitifully small time allocated. I wish it were different, but despite computational work being one of the important methods of research in physics, programming is not seen as a key part of a physics degree. And I thorougly concur with the comment about it being taught by the previous generation: many who were in charge of teaching or planning the computer modules had been using computers in the 1960's - which doesn't make it wrong, but provides a different outlook on today's systems. Peter ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
Re: [Edu-sig] Accessibility to non CS types?
At 22:13 29/05/2006, Bill Bradley wrote: Good gravy?! Where did you look? When I got my Physics degree we not only had to take programming, but we built 68K breadboard computers, programmed them in assembly (with a hex keypad) and used them to read and drive ADC/DACs to output on 'scopes. And no that was not during the Dark Ages, I got my degree in the 90s. Round most of the physics departments in the UK, where course details were available to the public via their websites. Do check back - does your physics department still do it, or has it fallen by the wayside as students arrive knowing less physics, so more 'core' material has to be crammed into the 3 years of a Bachelor's degree? Peter ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
Re: [Edu-sig] Accessibility to non CS types?
On 26/05/06, Paul D. Fernhout [EMAIL PROTECTED] wrote: I think Self leads the way here in generality with one inspector that canbe used to build GUIs, programs, or just sets of objects. And here is anattempt to bring that ease of use to Python, building on ideas from Self (and Squeak): :-)http://svn.sourceforge.net/viewcvs.cgi/patapata/trunk/PataPata/PataPata.py?view=logDoesn't succeed yet perhaps in making that beginner friendly, but a start. (PythonCard is much better choice for current work though.)Hello,I've just gave a try to your PataPata and I already have fun with it while testing it :) http://francois.schnell.free.fr/bazar/patapata-test1/patapata-test1.htmlWill it be possible to directly add new methods to morphs (maybe from the inspector ? ... when I saw the 'grow' method I wanted a shrink' one ...). Is there a way yet to execute a Morph method from another Morph (if I click on Morph 1 I'd like to execute method X from Morph 2 for example). I find your PataPata promising and I'm eager to see how it evolves :)francois --Paul Fernhout___Edu-sig mailing listEdu-sig@python.orghttp://mail.python.org/mailman/listinfo/edu-sig ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
Re: [Edu-sig] Accessibility to non CS types?
Andre Roberge wrote: ... Let me give a concrete example explaining inheritance for non-computer scientists. === class Father(object): ... class Mother(object): ... class Child(Mother, Father): ... === The computer scientists in the (virtual) room are probably horrified. Yup. I am aghast. You are using the built-from relationship. For yourself this is fine, but pedagogically it leads to very bad habits. The reason I am appalled is that I have maintained code that was written this way, and the mess that results over years of extending from such a shaky foundation is scary. I would claim the above example would be appropriate for the average person. I claim this is because you are a scientist, not a mathematician. At Penn, Mathematics was an Art, not a Science (I have great sympathy for that classification). You are in the habit of lying to your students and, next course, telling them you know, what you learned in the previous course was wrong. This is a reason for people leaving the sciences. Mathematicians tend to try to stick to truths, though they expand the universe they talk about each time. In part this distinction in approaches makes sense because mathematicians who make mistakes are corrected (and scorned) by other mathematicians, while physicists are corrected by reality (and refine their models). Computer Science is a funny field, reached from both mathematics and engineering, so the ideas you see there can come from either of these sides (and cause lovely fights in faculty meetings). I consider CompSci an architecture-like discipline, with mathematics holding the position in CompSci that physics has in architecture. Words like inheritance have been borrowed and adapted by computer scientists for use in their own discipline. While words like spin for physicists Natural languages seldom have precise definitions, and Computer Science is not close to the worst offender in this respect. To follow up on Kirby's personal history suggestion: I was a math loving kid by fourth grade, came to computers by accident in summer after 9th grade (in 1966) doing machine language on a vacuum tube computer (LGP-30). The following summer I spent full-time in an NSF-sponsored class at Penn where we a language a week for the summer (two programs per language). The experience gave me a good feel for what a programming language is in general, as well as specifically. I decided around 1972 (after auditing a class or two from Knuth) that I could be either a mediocre mathematician or a very good computer programmer. Twenty years ago I went back to school to attempt a PhD as a teaching union card in CompSci, and got a drop-out masters. For my research I was trying to do Query Optimization in Object-Oriented Databases, and glanced briefly at Python (the type system did not fit my research needs). After working in compilers and Databases after school, I picked up Python as a way of pursuing a long-running personal project, and had the most fun I've had in a new language in 30 years. --Scott David Daniels [EMAIL PROTECTED] ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
Re: [Edu-sig] Elementary graphics library
On 5/28/06, Paul D. Fernhout [EMAIL PROTECTED] wrote: If you haven't already, you could check out: Also: PIL.ImageDraw http://www.esrf.fr/computing/bliss/python2/pil/PIL.ImageDraw.html http://www.pythonware.com/library/pil/handbook/imagedraw.htm The ImageDraw module provide simple 2D graphics for Image objects. You can use this module to create new images, annotate or retouch existing images, and to generate graphics on the fly for web use. Aggdraw http://effbot.org/zone/draw-agg.htm The aggdraw module implements the basic WCK 2D Drawing Interface on top of the AGG library. This library provides high-quality drawing, with anti-aliasing and alpha compositing, while being fully compatible with the WCK renderer. Matplotlib http://matplotlib.sourceforge.net/ matplotlib is a python 2D plotting library which produces publication quality figures in a variety of hardcopy formats and interactive environments across platforms. matplotlib can be used in python scripts, the python and ipython shell (ala matlab or mathematica), web application servers, and six graphical user interface toolkits. Kiva http://code.enthought.com/kiva/ Kiva is a multi-platform DisplayPDF drawing engine that supports multiple output backends, including Windows, GTK, and Macintosh native windowing systems, a variety of raster image formats, PDF, and Postscript. DrawBot/NodeBox (OS X only, but useful as examples of simple 2D systems) http://drawbot.com/index.html http://nodebox.net/manual/reference/topics.php DrawBot is an powerful, free application for MacOSX that invites you to write simple Python scripts to generate two-dimensional graphics. The builtin graphics primitives support rectangles, ovals, (bezier) paths, polygons, text objects and transparency. PyCairo http://cairographics.org/pycairo Cairo is a library for drawing vector graphics. Vector graphics are interesting because when they appear on screen, they don't lose clarity when resized or transformed. --Dethe ___ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
