Mailman 3 February 2002 - Edu-sig

Re: [Edu-sig] Executable pseudocode / executable flowcharts
by Kirby Urner Feb. 18, 2002

Feb. 18, 2002

At 01:00 PM 2/15/2002 -0500, Todd Whittaker wrote: >Yes, I know that most folks don't use flowcharts, that >the belief is that they're outdated tools, pseudo-code is >better, and so on. But, for visual learners, an executable >flowchart can be a great tool (especially one that can be >stepped through like a debugger, complete with watch windows). Although not exactly what you have in mind, the Lego Mindstorms system is good for children and adults with no previous programming experience, in allowing the construction of programs as flowcharts. http://mindstorms.lego.com/ In the GUI, you drag canned actions (forward, turn left) as icons and sequence them vertically (called a "stack"). The canned actions come with tabs which open up wizards allowing some user-customizable parameters to be set. You can group sequences and give them names, at which point they condense into single blocks and list in the "My Blocks" palette (user-defined functions). You can sandwich blocks inside of repeat loops (Repeat Forever, Repeat Until etc.), define variables, insert conditional branches. Once you've defined a stack, you download it via infrared light beam to the RCX, a brick-shaped unit with sensor inputs and power outputs, to which motors are connected. Although there's no debugger per se, individual blocks can be "tried" (test download and execute). In a lot of ways, the experience from a kid's point of view is similar to controlling a graphical turtle through Logo, except here the "turtle" is a physical device, and the whole engineering angle of building robust "robots" is brought into the learning experience. On screen, a program is an executable flowchart (savable of course). A curriculum might start with Mindstorms at the 4th grade level, then move to a more fully developed concept of a programming language. The O'Reilly book introduces NQC (not quite C) as a way to program the RCX, and moves on to a version of FORTH. Kids would already have the algorithm-as-flowchart exposure through the introductory GUI. http://www.oreilly.com/catalog/lmstorms/desc.html Agilent has a product (looks like a reincarnation of what was formerly HP VEE) that allows graphical programming by hooking boxes together, using conditional branching. The same idea of user-definable parameters per box is implemented. Here the boxes may contain signal processing algorithms, such as a Fourier Transform or something. For many students, this would be a logical follow-on to the Mindstorms curriculum, as the robot has touch, light and other sensors, to which the algorithms respond. The VEE product is likewise all about processing sensor data in the lab. There's a freely downloadable trial version: http://www.get.agilent.com/gpinstruments/products/vee/download.shtml Kirby

1 0

Re: executable flowcharts--nsd-editor
by Christian Mascher Feb. 17, 2002

Feb. 17, 2002

> From: Todd Whittaker <todd(a)thewhittakers.org> > To: Python in education <edu-sig(a)python.org> > Subject: [Edu-sig] Executable pseudocode / executable flowcharts > > Hey all, > > I can make a good case in education for Python as a first language > because, as everyone claims, it it executable pseudo-code. I know it. I > believe it. I've made a case for it. But, where I work, our students > need more than just pseudo-code. What we need is a tool that lets > students create executable flowcharts as well. At http://www-iiuf.unifr.ch/sde/projects/kalt/NSD.html there is a small tool which lets you draw nassi-shneiderman diagrams and exports them to a file with pascal or c-code. I think this is really a neat little program, useful when teaching procedural programming at introductory level (control structures). Too bad it isn't geared for python where the translation between code and the nassi-shneiderman-diagram is very transparent due to the simple code formatting rules of python. If I had the time, I would pick something similar as a programming project in python. With such an editor you could also show your students that at the level of procedures python and pascal (and C, ...) don't differ much, its all the same kind of basic structure. I've also seen that for some beginners a flowchart is a great help in understanding the nature of an algorithm. Christian Mascher

1 0

Executable pseudocode / executable flowcharts
by Todd Whittaker Feb. 15, 2002

Feb. 15, 2002

Hey all, I can make a good case in education for Python as a first language because, as everyone claims, it it executable pseudo-code. I know it. I believe it. I've made a case for it. But, where I work, our students need more than just pseudo-code. What we need is a tool that lets students create executable flowcharts as well. Yes, I know that most folks don't use flowcharts, that the belief is that they're outdated tools, pseudo-code is better, and so on. But, for visual learners, an executable flowchart can be a great tool (especially one that can be stepped through like a debugger, complete with watch windows). Does anyone know of such a tool? If not, would there be interest in making it? I'm thinking some nifty features could be: 1. Draw flowcharts with Python expressions and statements in the graphical boxes. 2. Export the flowcharts as Python code. 3. Import Python code into a graphical flowchart representation. 4. Step through flowchart execution one statement at a time and view an output window and variable watch windows at the same time. This works best for procedural programming, and I have no idea how to represent OOP in a flowchart. Thoughts? -- Todd ------------------------------------------------------------- Todd A. Whittaker mailto:todd@thewhittakers.org http://www.thewhittakers.org/~todd/ -------------------------------------------------------------

3 4

Re: [PSF-Members] python domain
by Paul Prescod Feb. 13, 2002

Feb. 13, 2002

By the way, I own CP4E.org and cp4e.net. Happy to donate them to anyone who would use them for something Python and education related. I haven't bothered to make them aliases for the Python site because there didn't seem much point... Paul Prescod

1 0

New Python book
by Kirby Urner Feb. 12, 2002

Feb. 12, 2002

Greetings all: 'Python: How to Program' (2002, Prentice-Hall) is now available. It includes stuff on XHTML/CSS, XML, PyOpenGL, XML, interfacing with a database, CGI and more (even some stuff on 2.2 iterators and generators). It's designed as possible course text, with questions and exercises at the end of each chapter. Comes with CD, including the source code, Alice (multimedia package with Python API) and Apache web server. Kirby PS: I was a reviewer, doing testing and providing feedback on some of the chapters (one of many, see pg. LV). Just got my copy from the publisher yesterday. Dunno the sale price -- it's a 1300 page monster (plus CD) so probably in the $45-$60 range, judging from similar books. Wait, I should just check Amazon... yikes, $74. Well, like I say, it's a mighty thick tome.

1 0

Re: making an alias of a folder
by Christopher Smith Feb. 11, 2002

Feb. 11, 2002

Danny Yoo writes: <cut> > >I don't have a Macintosh available at the moment, so I can't test this, >but I believe that the macfs.NewAliasMinimalFromFullPath() is the function >that you're looking for: > > http://www.python.org/doc/current/mac/module-macfs.html I looked at that and didn't initially think that it was going to help but your saying it might be the thing made me look again. Though I don't know if I've got everything right, I do have a routine now that will make an alias of a folder. I don't understand the "relative" option yet, though. Those more in the know about the mac toolbox may see other things that I don't know as well. :-) Until the macostools.makealias is fixed, this is a workaround. Thanks for the nudge, Danny. And thanks for filing a bug report, Jack. /c #### import macfs from Carbon import Res # # Doesn't yet handle the relative option; I'm not sure what this # means for an alias yet. # def mkfolderalias(src, dst, relative=None): """Create an alias to a folder""" alias = macfs.NewAliasMinimalFromFullPath(dst) dstfss = alias.Resolve()[0] Res.FSpCreateResFile(dstfss, 'MACS', 'fdrp', -1) # make it point at the src and update the resource # {see Mac Lib Modules; v 2.2; sect 2.4.2 Alias Objects} # If the source is itself an alias, the new alias # will point at the same thing that the src alias is # pointing at. If the src is *not* a folder it will then # still point at the file but the icon will be a folder # icon until it is updated by the Finder (e.g. after # double clicking on it in the Finder). # alias.Update(src) h = Res.FSpOpenResFile(dstfss, 3) resource = Res.Resource(alias.data) resource.AddResource('alis', 0, '') Res.CloseResFile(h) # turn it into an alias icon; before doing this the # folder icon will be "busy and in use by the system" # dstfss = macfs.FSSpec(dst) dstfinfo = dstfss.GetFInfo() dstfinfo.Flags = dstfinfo.Flags|0x8000 # Alias flag dstfss.SetFInfo(dstfinfo) ####

1 0

making an alias of a folder
by Christopher Smith Feb. 11, 2002

Feb. 11, 2002

I think I put this request out before but haven't received any replies...perhaps there is someone new on the list that could help: Does anyone have a piece of code that successfully makes an alias of a folder on the MacOS? Even if you know how to do this in RealBasic or VisualBasic and could send me that code snippet I think it would be useful. I'm trying to complete a patch to a file copying routine. /c

3 2

Python for MS .NET?
by Louis Bertrand Feb. 7, 2002

Feb. 7, 2002

Hello all, I have no idea where to look for the answer to this request (see forwarded message below). I didn't see anything in the PEPs, and the only IDE for Python seems to be IDLE. Are there any hints that Python can be used as a language for .NET? Where else could I look? Thanks --Louis ---------- Forwarded Message ---------- Subject: Eiffel Is Available for VS.NET Date: Thu, 7 Feb 2002 08:04:02 -0500 An evaluation version of Eiffel is available for VS.NET. It appears to be a much bigger download than the Cobol download that I tried yesterday. Does anyone know of any other languages currently available in VS .NET? The proliferation of these extra languages and support by companies like Rationale may make VS .NET a must have for next September. I think that we should have a mini-seminar or workshop in May-June where each one of us could look at a .NET feature and help train each other. Other computer faculty should be invited to participate. John do you have a list of all of the programming related professors at the college? <|:-) Arthur J. Smith ------------------------------------------------------- -- Louis Bertrand <louis.bertrand(a)durhamc.on.ca> School of Technology, Durham College Oshawa, ON, Canada +1.905.721.3111 x2468

3 2

Contagious Fun => PythonStation => diskless linux stations
by Jason Cunliffe Feb. 6, 2002

Feb. 6, 2002

Greetings.. Yesterday at LinuxWorld Show in New York I saw Linux running on Sony Playstation2: http://www.cnn.com/2002/TECH/ptech/01/31/linux.ps2.idg/index.html http://playstation2-linux.com/ also lots of good information on linuxdevices.com: http://www.linuxdevices.com/news/NS3628477348.html which also points to nice Linux on DreamCast article: http://www.linuxdevices.com/articles/AT7466555948.html You probably won be surprised to hear SDL [Simple DirectMedia Layer] figures in this. Python has wrappers for SDL as used in PyGame http://pygame.org/ Stephen Figgins wrote an article last October about it: http://www.onlamp.com/pub/a/python/2001/10/04/pythonnews.html The action was all at the GPL .org booths. Some guys from the Japanese Linux Users Group had all sorts of cool thing going on, including Linux on Sega Dreamcast, and sundry other hand held computers and PDAs. The hack which caught my eye was a little tool called "ttrec". A small cli program which allows one to record and playback anything going on in tty terminal. An extension of the old Unix 'talk'. ttrec/ttplay is perfect for edu-sig because it does not behave like call and response port-based app. Instead it is natural VCR for console action. The flow is completely normal. Each character appears exactly as a entered by user or as computer echoes responses. Perfect for teaching python or any other cli activity in a shared environment or for later / remote use. The programmer told me it is a tiny c program he wrote. But by far the most edu-significant and exciting things I saw yesterday were developments for diskless workstations. There are a couple of closely related GPL efforts underpinning this: http://EtherBoot.org http://rom-o-matic.net http://ltsp.org Linux Terminal Server Project etherboot.org showed how one can take almost any ethernet card [$5 - $25] and install a ROM on it containing a tiny kernel. They This allows a PC to boot faultlessly from network server. The beauty is that one only has to maintain one central machine. Etherboot boots very quickly. Perfect for schools and classrooms. These guys are incredibly adept at writing tiny drivers and squeezing code onto EPROM's and flashdisks. It turns out that almost all BIOS with PCI will recognize these, and most ethernet cards have a vacant EPROM slot sitting there. The etherboot guys had a basketful of different cards on display and the list of supported hardware is impressive; Etherboot Network Interface Card Database http://etherboot.sourceforge.net/db/ LTSP is The complement to etherboot. Linux makes a great platform for deploying diskless workstations that boot from a network server. The LTSP is all about running thin client computers in a GNU/Linux environment. That means cheap silent PCs [no moving parts] which use standard keyboards mice and monitor. Boots in 22 seconds from a server. Then launches a XWindows GUI such as Gnome or KDE. viola! This is not gimmick, they had all kinds of heavy use running which we monitored remotely. The implications are many. Terminals are old idea in computers. What has changed is the price/performance of servers, Linux and all the desktop GUI applications now being developed. For schools.libraries etc this means the budget can go much further. Only one server to maintain. Cheap terminals everywhere else need no maintenance and can take the abuse typical of public computers. Jim McQuillan from LTSP said they have been working on it for 3 years. Now things are working well looking they are looking towards lots of exciting developments, including wireless and configuring with displays as one piece. He showed me a whitebox [diskless PC size of a small dictionary. Unit cost $400, but if he could order a container full [approx. 8000 units] from Taiwan the price drops to about $200 each. Add mouse, keyboard, monitor, extra RAM if desired.. The arithmetic per classroom/library is clearly very compelling. Lets say for every 20-40 terminals you need one good fast late model PC. The rest can be Cheap too expensive for you? I met a guy who lives in Delaware. Said his local recycling center [glass plastic etc] also has load of old PCs sitting there which nobody wants. These make perfectly good diskeless terminals. In his case he took them home and built a supercluster in his living room.. Go ahead let Bill Gates donate lots of hardware. Then strip em down and use etherboot and LTSP! A major issue for computing in schools/libraries is that people fail to understand/budget for maintenance and sysadmin. I was just reading about this problem in UK now. The above scenes depend on running ethernet to every station. Alternatives are to use wireless. There is a grassroots wireless movement in New York and elsewhere. NYCWireless.net has maps, links to other cities, how-tos etc. http://www.nycwireless.net/ http://www.nycwireless.net/links.html Looks like it is gonna be a very interesting year.. ./Jason ______________________________________________ Jason Cunliffe [NOMADICS: Director art+design] tel/fax: +1 718 422-1078 jasonic(a)nomadics.org N 43:00.000' W 074:31.875' ALT:1144 ft 84 Henry Street #3C Brooklyn NY 11201 USA

4 4

ttyrec => ePython distance learning..
by Jason Cunliffe Feb. 2, 2002

Feb. 2, 2002

For anyone interested here's Satoru Takabayashi's wonderful ttyrecpage: http://www.namazu.org/~satoru/ttyrec/ <description> ttyrec is a tty recorder. Recorded data can be played back with the included ttyplay command. ttyrec is just a derivative of script command for recording timing information with microsecond accuracy as well. It can record emacs -nw, vi, lynx, or any programs running on tty. </description> tty mania presents ttyrec videos. Please set your terminal size to 80x24 and have fun! http://tty.namazu.org/ rpms http://www.ping.de/~michael/RPMS/ ..etc ttyrec is immediately usable for anyone on Linux system, and I think any *nix including MacOSX. Seems to have been based on some Ruby work. I think it would be great to have a native python version of ttyrec/ttyplay built-in to all distros: IDLE, PythonWin, VPython, PyGeo, PythonCard, PyGame.. With or without that, E-Python tutorials, distance learning, training and seminars could take on a new kind of dynamic life. This is brilliant tool for learning/teaching the sequence rhythms of using Python. Literally, show what is programming? Installation how-tos Gathers stats on the main stumbling blocks, and behavior of beginners. feedback See how students progress. Preload lessons, libraries desmos and debugging. PythonLiveDoc: [Essential Reference, Standard Library] Learn by watching the masters at work. Support tool for pro-cli computer literacy presentations PythonTV ContagiousFun It exhibits a simple genius: lowfi/hifi, like VNC http://www.uk.research.att.com/vnc/ ./Jason ______________________________________________ Jason Cunliffe [NOMADICS: Director art+design] tel/fax: +1 718 422-1078 jasonic(a)nomadics.org N 43:00.000' W 074:31.875' ALT:1144 ft 84 Henry Street #3C Brooklyn NY 11201 USA

1 0