Re: concatenate the elements in each list of a list of lists
Am Wed, 23 Jul 2008 08:33:57 -0700 wrote antar2: I already asked a similar question, but encounter problems with python... How can I concatenate the elements in each list of a list of lists list_of_listsA = [['klas*', '*', '*'], ['mooi*', '*', '*', '*'], ['arm*', '*', '*(haar)']] wanted result: list_of_listsA = [['klas* * *'] ['mooi* * * *'] ['arm* * *(haar)']] Thanks a lot ! Hello, maybe this will help: In [5]: list_of_listsA = [['klas*', '*', '*'], ['mooi*', '*', '*', '*'], ['arm*', '*', '*(haar)']] In [6]: s = In [7]: print [[s.join(item)] for item in list_of_listsA] [['klas***'], ['mooi'], ['arm***(haar)']] regards Michael -- http://mail.python.org/mailman/listinfo/python-list
Re: Writing pins to the RS232
Jay,
Couple of points that may help you.
1) A serial port does not have data ports 0-n. A serial port takes a
byte (8 bits), then shifts them down a single pipe using a chip called a
UART (feel free to google for unfamiliar terms).
example
Bit pattern 1010 1010
would be shifted one bit at a time
1
0
1
0
1
0
1
0
a one is +5 volts on single send line of the UART and 0 is 0 volts.
RS232 uses a different mapping for 1's and 0's (but is still serial)
1 - ~-3V - -12 V
0 0-12 V
So you slap a chip on between the UART and the RS232 pin (usually a
MAX232) that translates the voltages for you.
On the other end of the wire
232 socket
MAC232
UART (usually built into the microcontroller)
Register in Microcontroller
I like playing at this level. I would recommend using AVR
microcontroller (easiest to program and there is an open source
gcc compiler).
for $20.00 US you can buy the butterfly eval board with:
- microcontroller
- max232 all wired up for rs232 connection from your computer
- lcd display
- temperature sensor
- light sensor
- the avr mega169 has many goodies
- analog - digital converter
- digital - analog converter
- LCD controller
This is a great bargin.
If you are starting out in microcontrollers. I would suggest that you
go to:
http://smileymicros.com/
They sell a nice package for $90.00
- butterfly eval board
- great, easy to follow book on how to develop on microcontrollers for
the beginer.
- project kit - includes everything you need to build all of the
projects (even includes the wire ;-)
There are python libs that support Ateml Avr connections:
It is easy to use your rs232 serial with a microcontroller at the other
end of the wire. Microcontrollers are cheap. If you fry why is
connected to your devices, you are only out the microcontroller.
Have fun,
Mike
[EMAIL PROTECTED] wrote:
I want to write to the pins of an RS232 without using the serial
protocol. The use would be every pin could act to complete a circuit
in customized hardware. I could use python to communicate serially to
a BASIC stamp or a Javelin stamp and then use the stamp to set however
many pins as 0's or 1's but should it be that hard to do with python.
I've looked through how python does serial with the serial module but
it just uses Java's javax.comm libraries. Is there anyway to do very
low level device writing to COM ports?
In summary I'm looking for something like:
ser = serial.Serial(0)
ser.pin0 = 1
ser.pin1 = 1
ser.pin2 = 1
or
ser.write('0xFF')
which would set 8 pins on the RS232 cable to 1's
--
The greatest performance improvement occurs on the transition of from
the non-working state to the working state.
--
http://mail.python.org/mailman/listinfo/python-list
Re: - E04 - Leadership! Google, Guido van Rossum, PSF
Congratulations to Guide, Mike Harald Armin Massa wrote: Guido at Google: a message in THE public forum c.l.p. A confirmation by Martellibot, that Guido is IN FACT sitting 15m distant from him; and everybody in Python knows where Martellibot has his desk. Can it get more official than this? yeah: a confirmation by Greg Stein @ Google within slashdot, that Guido is working at Google. I am sure that more people in the Python community are reading c.l.p. and /. than the washington post, the people affected have been informed. I guess that's as formal and official as it can get. And concerning Guido, Python, community and leadership: Guido is the designer, the creator of Python. He has nearly unlimeted trust in his design decisions: we all know, that he is THE gifted language designer. His proclamations are accepted because he has proven over time that he knows what's best for the language. Allow me to quote Greg Stein: Ha! Guido would quit in a heartbeat if you tried to make him manage people. That just isn't where he's at. He's absolutely brilliant and loves to write excellent code. Great. We're gonna let him do just that :-) So, Google with their geek-version of the Playboy-Mansion, free massage parleurs, free lunch and dinner and best recruitment tactics on the planet and the known universe will not be able to make Guido manage people. Somehow the Python community managed itself through the years... Python grew healthy and steadily; forked less then usual, inspired other languages and got faster and faster and faster. Maybe only mediocre and less ideas need a great leader. Maybe a great idea can lead for itself? Harald -- GHUM Harald Massa persuadere et programmare Harald Armin Massa Reinsburgstraße 202b 70197 Stuttgart 0173/9409607 -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: ANN: Dao Language v.0.9.6-beta is release!
[EMAIL PROTECTED] wrote: ,, info cut However there is one thing I don't like in python, that is, scoping by indentation. But it would not annoy me so much that make me decide to implement a new language^_^. Regards, Limin I find these comments interesting. It is very common for people to complain about indentation. I have helped several very large companies create C++ coding standards. One common requirement is very fixed indentation rules. These rules are often encoded into lint-like tools. These tools treat indentation errors like compile time errors. These are often the same people that don't want to use python because it uses indentation .. It is humorous if stand back and look from a distance greater then 10 feet :-) Mike -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: How to ping in Python?
I telnet to port 13 (returns time) Hope this is helpful, Mike Nico Grubert wrote: Hi there, I could not find any ping Class or Handler in python (2.3.5) to ping a machine. I just need to ping a machine to see if its answering. What's the best way to do it? Kind regards, Nico -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: How to ping in Python?
Les, I only ping internal machines. You are right about shutting down ports. When we disable telent, we also disable ping. Many people may not though, good luck, Mike Laszlo Zsolt Nagy wrote: Michael Schneider wrote: I telnet to port 13 (returns time) The problem is that most modern up-to-date servers use firewalls. They only open the ports that are absolutely necessary. Usually the time service is part of inetd, which is disabled by default, on most of the servers. PING ICMP may work, but sometimes it does not either. In the worst case, all port are closed and you have no way to tell if there is a computer or not. Can you tell more about what kind of server do you need to ping? Example: if you need to know if a web server is alive, you should connect to port 80 (http). If the connection was successful, you can close the connection immeditelly. You can expect a HTTP server to open the HTTP port, but all other ports may be closed. Les -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: Ant (with Python extensions) good replacement for distutils?
I would vote against ant because java must be installed to run it. The bootstrap install should be very simple. If you make python usage dependent on: 1) download java 2) install java 3) add java to path 4) download ant 5) install ant 6) add ant to path 7) download ptyhon 8) install python 9) add python to path 10) download package 11) run ant to install package just food for thought, Mike [EMAIL PROTECTED] wrote: I know distutils well but don't know anything about Ant except that it is a build tool from Apache project. Could it possible be better or as good as distutils? (There are extensions for Python.) Chris -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: Looking for small, impressive 3D-related Python script
Ken, I would suggest that you embed python in your app (very easy to do). -And convert several of your existing scripts to python. -Show them a stack of python books for customer training purposes - Drive excel with python (allows integration of your product with other products. - Pick an area of functionality that your product offers today that your customer would like to customize. - convert this alg to python - hack you product to execute the python script - code a variant of the alg in python - execute your variant to demonstrate that python can lower custom development cost, and provide points of extensibility Have fun, good luck, Mike Kenneth McDonald wrote: I'm not trying to persuade my company to offer Python as a scripting language for their product, but I am trying to give them examples of things that Python can do easily that cannot be done easily with their current proprietary scripting language. After that it would be their decision. As the product is a 3D package, I'm looking for something in this field. This does _not_ have to use PyOpenGL, or for that matter, any Python 3D package. In fact, my ideal would be a Python script that simply uses L-Systems (Lindenmayer systems) as in The Algorithmic Beauty of Plants, to generate plantlike OBJ files that can then be displayed in our program. In general, something that generates an OBJ file would probably be preferable to something that actually uses PyOpenGL, Blender, etc, as then I can just display the OBJ file in our program to say, This is the sort of thing that can be easily done by Python without recourse to any other programs. So please, any suggestions are welcome. As always, many thanks to this group, Ken -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: AJAX = APAX? Or: is there support for python in browsers?
Alex, Good point. Can python be used to write firefox extensions that could be called from javascript? 1) javascript would come in on the HTML page 2) javascript would communication with the Extension API 3) the extension would be written in python That way, you would only need to make your extension's API safe to the wild. It would require the user to download an extension, but flash, et all seem to do ok. Is this possible today? Thanks Mike PS. Sorry for my ignorance on this, I am a client-side developer, trying to explore serious client development. Alex Martelli wrote: Tim Roberts [EMAIL PROTECTED] wrote: ... Internet Explorer will allow any registered ActiveScript language to be used in a web page. Python qualifies. In the latest Win32 extensions, there is a script in win32comext/axscript/client/pyscript.py that will register Python as an ActiveScript language. The you can say script language=python print h1Hello, there./h1 /script Out of curiosity, how sandboxed is this Python? I remember a similar solution being withdrawn once because it wasn't really safely sandboxed, so the ``script'' could easily do any arbitrary damage to the machine... Alex -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: Using Which Version of Linux
I have been away from unix/linux for a couple of years. I went with SUSE. Just do an install all, and 10 gig later you are done. Very simple install, very easy admin with YAST. If you are a power admin, there may be better release. But if you want simple, but powerful, SUSE has worked well for me. Good Luck, Mike [EMAIL PROTECTED] wrote: ok, i m going to use Linux for my Python Programs, mainly because i need to see what will these fork() and exec() do. So, can anyone tell me which flavour of linux i should use, some say that Debian is more programmer friendly, or shold i use fedora, or Solaris. Because these three are the only ones i know of that are popular and free. -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: weakrefs to functions for observer pattern
Alex Martelli wrote: Michael Schneider [EMAIL PROTECTED] wrote: I would like to use weak refs in an observer pattern implementation. The problme that I have seems to be that weakrefs can't manage functions. They can manage just fine functions written in *Python*, just not builtin functions*, i.e., ones written in *C*. Just wrap any builtin function you need to register as observer into a tiny Python-coded wrapper and live happily ever after. ... Not all objects can be weakly referenced; those objects which can include class instances, functions written in Python (but not in C), Alex Alex, Thank you, I mis-read the docs. The mistake I made was having was using a weak reference as a key in the dictionary. Weak references will be very useful for me. I really enjoy python. So many good things have been added to the language without taking the fun away :-) Mike -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: Read/Write from/to a process
Jas, I use a python called twisted to run processes as you describe. Twisted is an event-driven framework that brings a change in the way that you look at things. take a look at: http://twistedmatrix.com/projects/core/documentation/howto/process.html Good luck, hope this is useful, Mike jas wrote: Hi, I would like to start a new process and be able to read/write from/to it. I have tried things like... import subprocess as sp p = sp.Popen(cmd.exe, stdout=sp.PIPE) p.stdin.write(hostname\n) however, it doesn't seem to work. I think the cmd.exe is catching it. I also tried f = open(out.txt, w) sys.stdout = f os.system(cmd.exe) ..but out.txt didn't contain any output from cmd.exe So, how can I create a process (in this case, cmd.exe) on Windows and be able to read/write from/to it? Thanks -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Problems with properties
Hello All, I have been working on learning how to use python properties. The get property access is working, but the the set property is not working. Rather then dispatching the property assignment to setNothing, the property object is being replaced with a string. I must be doing something very stupid here. Could someone please point out my error, I have dents in my forehead for this one. Thanks, Mike -- from unittest import TestCase import unittest class Task: def __init__(self,command): self._command = command def setNothing(self, value): raise AttributeError def getCommand(self): return self._command command=property(getCommand, setNothing) class taskTest(TestCase): def testTask(self): t = Task(dir c:) c = t.command self.assertEquals(dir c:, c) # should fail, but doesn't t.command = foo Bar self.assertEquals(dir c:, t.command) if __name__ == __main__: unittest.main() -- http://mail.python.org/mailman/listinfo/python-list
Re: Problems with properties
Thanks to all, I added the object as a subclass (should this be required for 2.4.1 ???) I also switched to the decorator with the @property syntax Thank you very much for the help for adding @property to the language. what a great language :-) Mike Michael Schneider wrote: Hello All, I have been working on learning how to use python properties. The get property access is working, but the the set property is not working. Rather then dispatching the property assignment to setNothing, the property object is being replaced with a string. I must be doing something very stupid here. Could someone please point out my error, I have dents in my forehead for this one. Thanks, Mike -- from unittest import TestCase import unittest class Task: def __init__(self,command): self._command = command def setNothing(self, value): raise AttributeError def getCommand(self): return self._command command=property(getCommand, setNothing) class taskTest(TestCase): def testTask(self): t = Task(dir c:) c = t.command self.assertEquals(dir c:, c) # should fail, but doesn't t.command = foo Bar self.assertEquals(dir c:, t.command) if __name__ == __main__: unittest.main() -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: Problems with properties
Thanks to all, I added the object as a subclass (should this be required for 2.4.1 ???) I also switched to the decorator with the @property syntax Thank you very much for the help for adding @property to the language. what a great language :-) Mike Michael Schneider wrote: Hello All, I have been working on learning how to use python properties. The get property access is working, but the the set property is not working. Rather then dispatching the property assignment to setNothing, the property object is being replaced with a string. I must be doing something very stupid here. Could someone please point out my error, I have dents in my forehead for this one. Thanks, Mike -- from unittest import TestCase import unittest class Task: def __init__(self,command): self._command = command def setNothing(self, value): raise AttributeError def getCommand(self): return self._command command=property(getCommand, setNothing) class taskTest(TestCase): def testTask(self): t = Task(dir c:) c = t.command self.assertEquals(dir c:, c) # should fail, but doesn't t.command = foo Bar self.assertEquals(dir c:, t.command) if __name__ == __main__: unittest.main() -- The greatest performance improvement occurs on the transition of from the non-working state to the working state. -- http://mail.python.org/mailman/listinfo/python-list
Re: So far
Take a look at: http://wingware.com/ It is only $35.00 for an IDE. (30 day free eval version) I use eclipse for java, and have become quite fond of tab completion. Mike CppNewB wrote: I am absolutely loving my experience with Python. Even vs. Ruby, the syntax feels very clean with an emphasis on simplification. My only complaint is that there doesn't appear to be a great commercial IDE for the language. I've tried Komodo, etc and they are nice applications, but they don't feel like they give me the power like a Visual Studio or Delphi (I wish I could articulate better the differences).Finding a descent GUI builder has been a challenge as well. Most of them have support for Dialogs, but what about more complex UI's? I may need a resizable frame within a resizable frame? I haven''t found a GUI builder with a great feel yet. Other than that, my experience has been wonderful. Even after my complaints, I plan on sticking with Python for a while. -- http://mail.python.org/mailman/listinfo/python-list
What python idioms for private, protected and public?
I have been following this thread with great interest. I have been coding in C++ since the late 80's and Java since the late 90's. I do use private in these languages, with accessors to get at internal data. This has become an ingrained idiom for me. When I create a python object, it is natural for me to want to use familiar idioms. Hare are the places where private is useful to me: Design Intent: 1) mark an object as dirty in a setter (anytime the object is changed, the dirty flag is set without requiring a user to set the dirty flag 2) enforce value constraints (even if just during debugging) 3) lazy init, don't bring the data in until needed 4) adding debug info 5) more here I do write code that violates private - memory ptr access in C++ - reflection in java - aspects in java I usually violate private when adding an aspect to a class, and I don't want this code in every class. Example, persistence. I really like the C# properties, you can access data with a data accessor, but add functionality is triggered when accessing the data. I like the data access syntax, better then the set/get functions. I need the functionality to achieve the design goals above, so i use function, but the are ugly, especially in math code. It would be easy for me to say Add public and private to python so I can code the way that I am used to. What are some python alternatives to achieve the design intents specified above above? Thanks Mike -- http://mail.python.org/mailman/listinfo/python-list
Re: What python idioms for private, protected and public?
Frederik, Thank you very much for the info on properties, that is very useful. Sorry about the public typo, that should have been protected. I should not post before coffee hits :-) Happy coding, Mike Fredrik Lundh wrote: Michael Schneider wrote: 1) mark an object as dirty in a setter (anytime the object is changed, the dirty flag is set without requiring a user to set the dirty flag properties. 2) enforce value constraints (even if just during debugging) properties. (when you no longer need to enforce things, switch back to a plain attribute). 3) lazy init, don't bring the data in until needed properties. 4) adding debug info properties. 5) more here properties. It would be easy for me to say Add public and private to python so I can code the way that I am used to. huh? what do private and public have to do with what you're describing? What are some python alternatives to achieve the design intents specified above above? properties. http://users.rcn.com/python/download/Descriptor.htm#properties /F -- http://mail.python.org/mailman/listinfo/python-list
Re: 1 Million users.. I can't Scale!!
I would need to get a better picture of your app. I use a package called twisted to handle large scale computing on multicore, and multi-computer problems http://twistedmatrix.com/ Hope this is useful, Mike yoda wrote: Hi guys, My situation is as follows: 1)I've developed a service that generates content for a mobile service. 2)The content is sent through an SMS gateway (currently we only send text messages). 3)I've got a million users (and climbing). 4)The users need to get the data a minimum of 5 seconds after it's generated. (not considering any bottlenecks external to my code). 5)Generating the content takes 1 second. I'm considering moving to stackless python so that I can make use of continuations so that I can open a massive number of connections to the gateway and pump the messages out to each user simultaneously.(I'm thinking of 1 connection per user). My questions therefore are: 1)Should I switch to stackless python or should I carry out experiments with mutlithreading the application? 2)What architectural suggestions can you give me? 3)Has anyone encountered such a situation before? How did you deal with it? 4)Lastly, and probably most controversial: Is python the right language for this? I really don't want to switch to Lisp, Icon or Erlang as yet. I really need help because my application currently can't scale. Some user's end up getting their data 30 seconds after generation(best case) and up to 5 minutes after content generation. This is simply unacceptable. The subscribers deserve much better service if my startup is to survive in the market. -- http://mail.python.org/mailman/listinfo/python-list
Python OGL Shader Programming
Just curious, is anyone using python for OGL 2.0 shader language development? Which lib are you using? Thanks, Mike -- http://mail.python.org/mailman/listinfo/python-list
