🌐 Mailman 3 December 2005 - Python-list - python.org

build curiosities of svn head (on WinXP)
by David Murmann Jan. 12, 2006

Jan. 12, 2006

hi all! i just built revision 41809 under winxp using a rather uncommon setup (at least i think so). since i have no visual studio here, i only used freely available tools: cygwin to get the source, the microsoft compiler/linker and NAnt (nant.sf.net) as the build tool to interpret the .vcproj-files (which may be the uncommon part). as far as i understand this setup is not supported in any way, but i noticed two problems, that could be interesting for others as well. first, the ProjectGUID's in "pythoncore.vcproj" and "pcbuild.sln" mismatch, i fixed that locally by changing "pythoncore.vcproj" (maybe visual studio is ignoring/shadowing this problem?). second, the build order in "pcbuild.sln" for elementtree seems to be wrong, nant tried to build elementtree before pythoncore (which failed). i fixed this by building elementtree separately. so my question is: will something like this be changed to support this setup (or at least to get the project files "cleaner")? should i submit a patch and see if it gets accepted? apart from that everything went fine, and i could reproduce the expected failure (ATM) of the regression test suite: http://mail.python.org/pipermail/python-dev/2005-December/059033.html btw, if anyone is interested in the (rather small) build-script for nant, just ask, so long, David.

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Re: Indentation/whitespace
by thakadu Jan. 12, 2006

Jan. 12, 2006

I consider myself a fairly experienced Python coder and although I am not "uncomfortable" with significant whitespace there are a few places where I do find it annoying and I wouldnt mind an alternate block delimitation syntax. I would prefer something like the ruby "end" though rather than '{' and '}'. The place I find it annoying is in pasting snippets of code from say web pages. I very often google for a piece of code and then paste it into my editor and almost always the pasted piece of code has different indentation and causes a compiler error. Sometimes in vim "100==" fixes it but very often not. It would be nice if you could use an "end" delimiter for quick experimentation with code and then later on go and remove the "end" and fix the indentation.

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Indentation/whitespace
by Joe Jan. 12, 2006

Jan. 12, 2006

Is Python going to support s syntax the does not use it's infamous whitespace rules? I recall reading that Python might include such a feature. Or, maybe just a brace-to-indentation preprocessor would be sufficient. Many people think Python's syntax makes sense. There are strong feelings both ways. It must depend on a person's way of thinking, because I find it very confusing, even after using with Python for some time, and trying to believe the advice that I would learn to like it. The most annoying thing is that multiple dedents are very unreadable. I still don't understand how anybody can think significant-but-invisible dedentation is a good thing. Note: No need to follow up with long opinions of why indentation is good -- they have been posted hundreds of times. It just seems that Python developers think the whitespace thing is only an issue for newbies. I think that many experienced users don't learn to like it, but instead just learn to live with it.

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PYTHONDOCS
by J. D. Leach Jan. 9, 2006

Jan. 9, 2006

OK, I'm stupid. I have been unable to discern (even Googled) a way to set the PYTHONDOCS variable to point to where the HTML files are. What to do? I need to know the process and where theses variables are stored. -- J. D. Leach Columbus, Indiana USA Linux/Open Source Computer using: Mandrakelinux release 10.2 (Limited Edition 2005) for i586 kernel 2.6.11-6mdk

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Python on Nintendo DS
by lickspittle＠gmail.com Jan. 9, 2006

Jan. 9, 2006

Hi, I tried porting Python to the Nintendo DS, and it was surprisingly easy. Installing something called devkitPro, devkitARM, libNDS, msys, msys-DTK and then just using that to cross compile a python installation. Heres a screenshot of it running in the Dualis emulator. It runs flawlessly for what has been compiled into it: http://img520.imageshack.us/img520/2145/python240cj.jpg You can download the source code to link against the static library and add a method of input (which you can see in the picture). Also included is a .nds file for running on your Nintendo DS: http://files.filefront.com/NDSPythonStuffzip/;4497277;;/fileinfo.html You click on keys on the touch screen to enter input. Notes: The clicking on keys in the emulator is extremely non-responsive, on the DS, it is perfect. Also, the emulators do not handle displaying the right bits and pieces to the right screen, so the keyboard is displayed on the top screen and the console on the touch screen (so its kind of hard to use as you can't see the regions on the touch screen to click on). The .nds file can be recompiled to use the lcd screens right for emulators, but the .nds file was compiled to work correctly on a DS. A problem.. On Dualis, the interpreter works perfectly. However, on the Nintendo DS, it is completely unreliable and seems to corrupt at random points. Occasionally you can get to the command line and enter one command or two, but its guaranteed to corrupt at some point. I have no idea why this is. I have to assume that Dualis implements the processor and hardware specs more flexibly than they actually are on the DS. And that there is some way the compilation options or linking options can be modified to restrict the output to what the DS can actually run. If anyone has the time and interest to give it a shot at getting it working, you will need a Nintendo DS with some form of homebrewing hardware which lets you put storage mediums into the DS with custom media.. like compiled .nds files. I use a Supercard, the compact flash version. As for the installation of tools required to compile .nds files, I used the following page: http://www.double.co.nz/nintendo_ds/nds_develop1.html Then I went to the mingw sourceforge page and got msys-dtk and installed that so that I would have autoconf and automake. Then I extracted Python2.4 source code and opened a dos console, cd to the directory with the Python source code and type the following: set BASECFLAGS=-mcpu=arm9tdmi -mtune=arm946e-s -ffast-math -mthumb -mthumb-interwork -DARM9 set CFLAGS=-mcpu=arm9tdmi -mtune=arm946e-s -ffast-math -mthumb -mthumb-interwork -DARM9 set LDFLAGS=-specs=ds_arm9.specs -g -mthumb -mthumb-interwork -Wl,-Map,libpython2.4.map sh configure --host=arm-elf This should give you a makefile, now you need to edit it. Change AR to have a value of arm-elf-ar (configure doesn't pick that up properly). Also, where there are references to OBJECT_OBJS, you need to also enter NDS_OBJS to get included along with it. And enter the following in the makefile somewhere, maybe after OBJECT_OBJS NDS_OBJS = RISCOS/Python/getcwd_riscos.o Also, go into Modules and edit Setup. Comment out all four of the modules still listed uncommented in the same block, posix, errno, ... Now in the top level python source code directory, type make. It should make and then error claiming it can't link against some function to do with ThreadState, locate all calls of that function in Python/pystate.c and comment them out -- this is a bug in the Python 2.4.2 source distribution that pops up when threads are disabled. Now it should compile the static library and error on the python.exe (which is of no use to us). You should now be able to compile the contents of NDSPythonStuff.zip against that library (you'll need to make cosmetic changes to the Makefile of course). Anyway, if anyone can help with working out how to change the compilation or linking options to get the code to work properly on the DS, please email me.

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Worthwhile to reverse a dictionary
by rudysanford＠hotmail.com Jan. 8, 2006

Jan. 8, 2006

I just started messing with programming and started with Python. Part of my first project deals with translating numerical values to letters. I would like to be able to do the reverse as well, letters to numbers, sort of a table for lookup and a table for reverse lookup. I thought that a dictionary would be the structure to use- write it once and in a second instance swap the keys for values and values for keys. However, reversing a dictionary does not seem to be easily achieved. Am I using the wrong data structure?

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Re: - E04 - Leadership! Google, Guido van Rossum, PSF
by Anton Vredegoor Jan. 7, 2006

Jan. 7, 2006

Robert Kern wrote: > I have a friend who works at Google. He has no backstabbing history at all. Stop > insulting my friends. Your friends work for people who would never hire me. My resume sucks, but I'm not a bad person or a mediocre programmer. They sold out. > For Software Engineer: > > """ > Requirements: > > * BS or MS in Computer Science or equivalent (PhD a plus). Right here. > * Several years of software development experience. > * Enthusiasm for solving interesting problems. > * Experience with Unix/Linux or Windows environments, C++ development, > distributed systems, machine learning, information retrieval, network > programming and/or developing large software systems a plus. > """ > > I don't see any "damaged soul" requirement. I do. Experience here is an eufemism for having worked for the man. > >>(Especially if he uses PyPy to experiment and play in ... :) > > > > Yes PyPy could save Python, or destroy the world. I have the impression > > not many enough people realize that a selfhosting programming language > > is something on the same level as a nano assembler or an artificial > > intelligence. > > ??? What the hell are you smoking? We already have self-hosting programming > languages. Yes. We have humans too. > > Anton > > > > 'make my day, prove me wrong' > > Prove yourself right. Ok. That's a bit harder. I suppose we agree that if we have an intelligent program that is more intelligent than a human and have this program design an even more intelligent program than things start to accelerate pretty fast? Now the combination of a programmer with a tool (program) that can be used to make a better tool. This gives a better human-machine combination, which then can be used to further improve the combination. I don't think I have completely proven my point now, but since the danger is very real and big, coming close is already reason enough to watch this carefully. Why hasn't it happened yet with lisp? I don't know, why didn't the world get destroyed by all out atomic warfare? Couldn't it have happened? If we create AI why would AI keep us around if we ourselves won't even hire people that do not comply to absurdly specific preconditions? Don't we let our poor people starve in the undeveloped countries or even in our own cities? If we want to prove we belong to the next world we should start now. Open work communities where everyone can start working and get paid. The same thing as open source code or usenet but now with money for everyone. Anton 'sorry, I don't want to start a flamewar, but I really believe what I wrote here'

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python speed
by Krystian Jan. 7, 2006

Jan. 7, 2006

Hi are there any future perspectives for Python to be as fast as java? i would like to use Python as a language for writing games. best regards krystian

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nesting for statements?
by tpcolson＠gmail.com Jan. 6, 2006

Jan. 6, 2006

I'm not what you'd call a "programmer" of any sort, so perhaps this question may seem arcane and result in a plethora of "you idiot" threads, but here goes: ArcGIS 9.1 has a neat interface with python (2.1-2.4), allowing me to do all sorts of spatial operations within python, namely, repetitive functions. In the below code, I'm trying to iterate thru multiple values of the variable "Discretisation error factor" using a for statement that temporarily populates "Disc", which is used as input in "Discretisation error factor" in the gp.TopoToRaster._sa function. For each iteration of "Discretisation error factor", I'm trying to name the output file "outa", "outb", "out...." Not quite sure how to implement that. There are lots of examples on nested for loops out there, but nothing on combing that with a output file naming sheme. The gp.TopoToRaster_sa function by itself without all the for statements works fine. Appreciate any help on this, other wise I have to manually interpolate hundreds of LiDAR point clouds, each, 10 times for diff. values of DEF. # TopoToRaster_sample.py # Description: Interpolate a series of point features onto a rectangular raster using TopoToRaster # Requirements: None # Author: ESRI # Date: 12\\01\\03 # Import system modules import sys, string, os, win32com.client # Create the Geoprocessor object from win32com.client import Dispatch gp = Dispatch("esriGeoprocessing.GpDispatch.1") # Check out any necessary licenses gp.CheckOutExtension("spatial") # Iterate 2 thru 4 in increments of 2 for DEF # Name the "2" dem "outa" and the "4" dem "outb" for x in range(2,4): Disc = int(x) names = ["a","b"] for y in names: Out_Dem = "out"+y try: # Process: Topo to Raster... gp.TopoToRaster_sa("C:\\temp\\falls_lidar.shp Z PointElevation", Out_Dem, # Variable for name of output raster. This should increment name of output based on the for statement "5", # Output raster cell size: each pixel is 5 feet by 5 feet "2103763.27 813746.12 2111850.32 822518.65", #extent of raster borders, SPF, NC, NAD83 "20", # #Grid Margin "", #Smallest z value to be used in interpolation (optional) "", #Largest z value to be used in interpolation (optional) "NO_ENFORCE", #Drainage option "SPOT", #Spot data option "40", #Maximum number of iterations (optional) "", #Roughness penalty (optional) Disc, #Discretisation error factor: This should increment DEF based on the for statement "0", #Vertical standard error (optional) "", #Tolerance 1 (optional) "" #Tolerance 2 (optional) ) except: print "ERROR OCCURED" print gp.GetMessages()

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Application architecture (long post - sorry)
by limeydrink＠hotmail.com Jan. 6, 2006

Jan. 6, 2006

Hi all, I want to create a mobile field worker data solution. Let me explain... I work for a company that has some software used by call takers to enter information into a database about faults with electrical appliances they manufacture, sell to customers, and then provide maintenance contracts for. The company has a number of field workers (growing number) servicing these appliances, and information about the faults and customer locations is fed to them by printing off job sheets from the call taking system and then either faxing them to the engineers or the engineers drop in to the office and collect them. There are lots of problems with this, such as lost job information, incomplete forms, incorrect non validated data, the cost of printing off job sheets and also the engineers having to collect, regular phone calls to the engineers to update them on call informtion, and then the fact that all this data then has to be inputted back into another system manully. Basically I want to create a means of getting this data to them electronically. I know there are a few companies who could provide this solution but they are very expensive and possibly overkill at the moment, we could start developing our own basic system then it can grow over time. I have looked at the options for developing the client for these "electronic job sheets" and have decided upon Microsoft Pocket PC and the .net compact framework. It seems the easiest environment for developing and the PDA's can be obtained very cheaply as a package from a GSM/GPRS data carrier. The server side is where cost savings can be made and so i have decided on a linux based server side using a database backend such as PostgreSQL. It would be usefull (and preferable) to make the server side of the applicaiton portable, I have looked at Java and quite frankly I have gone off the idea, it seems too complicated and I don't need to have my application tick all the buzzword boxes - basically it doesn't need to be a fashionable solution and if it did I would run it all under Windows and .net from client to server. I have decided on Python (hopefully your advice will confirm to me it's the correct decision) I have not developed any software of this type before and the trouble I am having is deciding on how to interface between the client apps and the server side. Problem 1 - Physical connectivity how would I make the actual network connection in to the server from the client Running a VPN connection over GPRS ? Connecting to the web on the client then using web services ? The above decisions probably depend on the answer to problem 2... How to connect to the data If I have a VPN connection to the network as described above could it be just as simple as using ODBC to connect to the server and access the data like just any other database application (not knowing how network heavy this would be over a much slower connection than a LAN) Or even simpler I could just export data for the engineers into XML or .csv files and expose them using a web server the client then just connects to the server and then downloads the job data , and uploads completed job information Or (this is where the bulk of the python part comes into it), I create a network server in Python that the clients connect to this could be a two way thing then, as the client app could connect first thing in the morning and collect jobs but I could also push data to the client such as job updates and notifications making it much smarter and interactive. There are currently around 60 engineers and they will be requesting data at specific times, first thing in morning and probably midday being the most busy times where probably all engineers will be connecting at once. So if I go down the network server route it will have to handle multiple connections from clients and then connect to a database to retrieve job information for each specific engineer and then send over the connection to the client. The number of engineers is increasing steadily and so this application needs to be fairly scaleable. I have a grander plan for this, as much of the work will be done in my own time, as sort of a pet project, and if possible I would like to make the application customizable and maybe even sell to other companies although lets not run before we can walk eh :) I know this post isn't Python specific but there are some smart guys on here that could point me in the right direction or at least give me something to think about :) Thanks in advance

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