🌐 Mailman 3 February 2007 - Tutor - python.org

Send binary/hex data to a TCP socket
by Tod Haren July 19, 2011

July 19, 2011

I need to send a server at the other end of a socket a 36 byte "frame", where each byte represents a specific field in the custom data structure. (If there are any Ham operators reading this, I'm talking about the AGW Packet Engine) The documentation for the server says to initialize each field to a binary zero(0x00). How do I get a binary zero in Python? The next step is to send this all to the server and subsequently receive a similarly formated frame. A very basic frame looks something like this(modified from documentation): |00 00 00 00 4D 00 00 00 00 00 00 00 00 00 00 00 |....M........... |00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................ |00 00 00 00 |.... My problem is that hex(0) return '0x0' and hex(ord('M')) returns '0x4d'. If I concatonate these all together then the socket receives 109 bytes instead of 36. The documentation examples are in C++, so they are little help to me. The examples make use of the MoveMemory function for building the frames, but I'm clueless what that does. Pseudo code for the frame above: l = [] for i in xrange(36): l.append(hex(0)) l[4]=hex(ord('M')) d='' d=d.join(l) #I need some other data type to send besides a string! sock.send(d) #send the 36 bytes to the socket Any pointers or references would be greatly appreciated.

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Tracking time
by Michael Key Jan. 7, 2010

Jan. 7, 2010

I am trying to develop a project tracking program that would allow you to track hours and minutes spent on several different projects and store he data in a database for printing. Any help would be appreciated. Mike

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difflib.SequenceMatcher with get_matching_blocks is incorrect
by Thomas Nov. 5, 2007

Nov. 5, 2007

I'm trying to write a program to test someone's typing speed and show them their mistakes. However I'm getting weird results when looking for the differences in longer (than 100 chars) strings: import difflib # a tape measure string (just makes it easier to locate a given index) a = '1-3-5-7-9-12-15-18-21-24-27-30-33-36-39-42-45-48-51-54-57-60-63-66-69-72-75-78-81-84-87-90-93-96-99-103-107-111-115-119-123-127-131-135-139-143-147-151-155-159-163-167-171-175-179-183-187-191-195--200' # now with a few mistakes b = '1-3-5-7-l-12-15-18-21-24-27-30-33-36-39o42-45-48-51-54-57-60-63-66-69-72-75-78-81-84-8k-90-93-96-9l-103-107-111-115-119-12b-1v7-131-135-139-143-147-151-m55-159-163-167-a71-175j179-183-187-191-195--200' s = difflib.SequenceMatcher(None, a ,b) ms = s.get_matching_blocks() print ms [(0, 0, 8), (200, 200, 0)] Have I made a mistake or is this function designed to give up when the input strings get too long? Thanks in advance, Thomas

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ossaudiodev, pygtk, and flushing buffers
by Matthew White Aug. 3, 2007

Aug. 3, 2007

Hello All, I'm writing a little audio player that plays voicemail files. (I realize I'm reinventing the wheel, but it's still fun.) The problem I'm experiencing is that I'm hearing the last fraction of the sound clip twice, either when the clip is done playing or when the program exits. I've tried a few things and none of them have worked. The bit of code that does the playing is here: def play(self): if self.data_written < self.file_length: buf = self.data.read(self.buf_size) self.data_written += self.dsp.write(buf) self.percent_done = self.data_written / self.file_length if self.data_written == self.file_length: self._reopen_audio_device() This causes the second playing of the "last little bit" when the end of the file is reached. When I don't include the second if statement, the "last little bit" gets played when the program exits. According to the documentaiton, closing the audio device will flush any data in the sound card buffer. I guess what I'm hearing is that buffered clip being flushed. I've thought about using the mixer device to put the volume to zero, flush the buffer, then turning the volume back up again, but that seems like a hack. If anyone decides to use this program, you'll need to use a .wav file and change the value of self.sample_rate in vmPlayer.py from 8000 to 44100 (or whatever rate your file is encoded in) (Also, I plan on auto-detecting the sample rate in the future. I hard coded 8000 because that's the rate the voice mail system uses.) See attached files for the code. -mtw

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SPE - Stani's Python Editor ?
by Vladimir Strycek June 24, 2007

June 24, 2007

Hi all, some time ago i instaled SPE with python 2.4... it works very good... but yesterday my pc crash completly ( some dll went missing somehow :-) )... so after format and reinstalling of windows i begin to install all my programs back... When i come to python i download new 2.5 version and only version for win i could find is SPE-0.8.2.a-wx2.6.1.0-py24 which doesnt work... :-( newer version ist just rpm and i need exe for win... any idea if there will be exe or any more development in SPE cause homepage is not running etc... Or can you suggest similar IDE for python... ? Thanks Best regards Vladimir

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geeks like us and the rest of THEM
by Kirk Bailey March 4, 2007

March 4, 2007

OK, my project is to come up with a wiki which is easy to install and use in a windows laptop, to wikify the notebook into a hypernotebook. ok, it must be EASY to install. And LEGAL. MiniWiki is in python. I can do it in a self extracting installer as there is a nice free pone out there someplace- links please? BUT PYTHON IS ANOTHER MATTER. It needs to have python on the notebook, which is not the case. It aldso needs a small server in the notebook, and I have one in python and another in C++, which alas is not freeware. The hurdle is it must be a legal and simple and almost droolproof solution from soup to nuts. the beta solution is working in this laptop NOW. Now how do I turn this into a turnkey solution for THEM? We are geeks. But the end result is intended for pointy haired bosses, soccer moms with Avon dealerships, and other regular humans. And as awlays, we must avoid the dread lawyer vampires. -- Salute! -Kirk Bailey Think +-----+ | BOX | +-----+ knihT Fnord.

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dictionaries and memory handling
by Arild B. Næss March 3, 2007

March 3, 2007

Hi, I'm working on a python script for a task in statistical language processing. Briefly put it all boils down to counting different things in very large text files, doing simple computations on these counts and storing the results. I have been using python's dictionary type as my basic data structure of storing the counts. This has been a nice and simple solution, but turns out to be a bad idea in the long run, since the dictionaries become _very_ large, and create MemoryErrors when I try to run my script on texts of a certain size. It seems that an SQL database would probably be the way to go, but I am a bit concerned about speed issues (even though running time is not all that crucial here). In any case it would probably take me a while to get a database up and running and I need to hand in some preliminary results pretty soon, so for now I think I'll postpone the SQL and try to tweak my current script to be able to run it on slightly longer texts than it can handle now. So, enough beating around the bush, my questions are: - Will the dictionaries take up less memory if I use numbers rather than words as keys (i.e. will {3:45, 6:77, 9:33} consume less memory than {"eloquent":45, "helpless":77, "samaritan":33} )? And if so: Slightly less, or substantially less memory? - What are common methods to monitor the memory usage of a script? Can I add a snippet to the code that prints out how many MBs of memory a certain dictionary takes up at that particular time? regards, Arild Næss

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howto call DOM with python
by Ismael Farfán Estrada March 3, 2007

March 3, 2007

hi there I was wondering wheter someone knows how to use python to write a client-side scripts like if it were java, I want to get someting like this working <html> <script type="text/python"> window.alert("python") </script> </html> but nothing happens. I don't know javascript but this code works if I put javascript instead of python, I've also tried with pythonscript python-source, etc hope you can help me, I'm using GNU/Suse, Opera, and Firefox for test _________________________________________________________________ El mejor destino, con los mejores contenidos http://www.prodigy.msn.com

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httpd in your laptop?!? serve web pages and wikis in your notebook?
by Kirk Bailey March 2, 2007

March 2, 2007

ok, I realized SOME TIME BACK that to run MANY THINGS in your windows computer you need a server in there- and a nice SMALL one if it is going to coexist with everything else going on. I found one in python, and posted it, and it caused a stirr. Well, I found a LISTING of them, and tried all the more promising ones. here is that page: http://microsoft.toddverbeek.com/phttpd.html In breif, they are: xitami - fast, powerful, and the basic version is free. Omnihttpd - looks good, very configurable, maqny features. Sambar - many features, more thsan just httpd by a long shot. Savant - SECURE? in my laptop? well, so it says. MAny other features. MiniPortal - includes apache and ftp and a web baised control panel. possibly this is overkill? BadBlue - it talks a good fight, but I found it's setup and installation confuising. possibly a criticism of it's documentaion, or maybe a lack of coffee on my part. give it a look. Viking - another does everthing server. this includes dns and web mail and hosting lists and... jeez louise, will it wask my car? INframail - from the site: "...Inframail is a combination mail/web/ftp/news/gopher server, available in different versions with varying capabilities, all of them inexpensive." Not free, but cheap. SompleServerWWW - trivally easy to install. but not easy to bend to my will. I have to reorganise mu directory tree to suit it, as I could not conviently discover a way to tell it where my webpages live. Maybe studying the manual at length will reveal this, but it is not obvious. Is this a criticism of myself, the program, or the docs? Hmmm... Serving - not to be found on host site. ??? Falcon- limited, but good if it's limitations do now hamper your needed application. it concerned me, so I gave it a miss. TinyWeb - Ignoring the name thing, it is pretty simple to use, is configured witrh command line arguements (old BBS sysop that I am, this is nothing new) and the impact on my laptop was- none. as in less than 1% cpu usage, memory requirements that sound like the guts of my digital watch. And it works. it hosts scripts, invokes python, hands off environment variables, works with the directory tree the way I set it up, and is very sparing with my resources. and it's free. This one is a definate looker, check it out and see if it suits your needs. A GUI front end is available if you want it. Both are $free$. MacHttp - beats me, I do intel/pc stuff. No opinion. RobinHood - did not evalulate. Smallhttps - VERY good, many features, powerful, web management and configuration. $25.free version limits how many simultanious connections to 3, and only licenses for 21 days. Russian author is not ideal for documenting the work for english reading eyes, but I managed. It's VERY good, and my second choice for my personal server. So there it is, click to read the page and go from there and see if something suits ytour needs and wallet. For now tiny is serving my needs with complete satisfaction. I may write a tiddlywiki manual for it as a donation to support the project. -- Salute! -Kirk Bailey Think +-----+ | BOX | +-----+ knihT Fnord.

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Problem with Import
by Nagendra Singh March 2, 2007

March 2, 2007

Hi all, I am running python on Cygwin and I have also installed gdal which is a raster translator library. When I run the command import gdal, Python gives me an error : Python 2.4.3 (#1, May 18 2006, 07:40:45) [GCC 3.3.3 (cygwin special)] on cygwin Type "help", "copyright", "credits" or "license" for more information. >>> import gdal Traceback (most recent call last): File "<stdin>", line 1, in ? File "/usr/lib/python2.4/site-packages/gdal.py", line 191, in ? import _gdal ImportError: No module named _gdal The file gdal.py and gdal.pyc are in : /usr/lib/python2.4/site-packages, but still it gives this error. Thanks Singh

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