🌐 Mailman 3 February 2011 - Tutor - python.org

Wave module
by Alex Krycek Feb. 12, 2015

Feb. 12, 2015

Hello, I'm trying to join two .wav files with the wave module. But when I try to use wave.open(filename, "rb") I receive the following error: Traceback (most recent call last): File "<stdin>", line 1, in <module> File "F:\PortablePython1.0\lib\wave.py", line 483, in open return Wave_read(f) File "F:\PortablePython1.0\lib\wave.py", line 162, in __init__ self.initfp(f) File "F:\PortablePython1.0\lib\wave.py", line 143, in initfp self._read_fmt_chunk(chunk) File "F:\PortablePython1.0\lib\wave.py", line 264, in _read_fmt_chunk raise Error, 'unknown format: %r' % (wFormatTag,) wave.Error: unknown format: 85 I read somewhere that there are various wave formats, only some supported by Python. Is this true? If so, is there any way I can convert my wave files into a supported kind? Thanks!

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Running .py files in shell
by Kevin Rapley Sept. 22, 2011

Sept. 22, 2011

Hello all, I am new to programming and have opted to learn Python as I hear it is a good first language. I am currently going through the exercises in 'How to Think Like a Computer Scientist: Learning with Python 2nd Edition'. I am running Mac OSX v10.6.4 Snow Leopard I am running Python 2.6.1 I have a couple of questions: 1. How do I execute .py files in the command line shell? I have my files in /Users/Kevin/python-exercises/ and am opening python in shell from that directory 2. How do I install GASP which is referenced in chapter 4? The instructions in this book are not complete. I have researched and found a reference on Stack Overflow which is contributed to by GASP programmers http://stackoverflow.com/questions/1024862/how-do-i-install-gasp-for-python… I have MacPorts installed and have attempted to install PyObjC, which is referenced as a prerequisite to PyGame and GASP. I get the following error when attempting to install PyObjC: sudo port install py-pyobjc Password: ---> Computing dependencies for py-pyobjc ---> Fetching py-pyobjc Error: Target org.macports.fetch returned: PyObjC 1.4 is for Mac OS X 10.4 and lower. On 10.5, use py-pyobjc2 instead. Log for py-pyobjc is at: /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_python_py-pyobjc/main.log Error: Status 1 encountered during processing. It says to use py-objc2 instead, so I do so and get this error: sudo port install py-pyobjc2 Error: Target org.macports.activate returned: Image error: /opt/local/lib/python2.4/site-packages/modulegraph/__init__.py is being used by the active py-modulegraph port. Please deactivate this port first, or use 'port -f activate py-modulegraph-devel' to force the activation. Log for py-modulegraph-devel is at: /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_python_py-modulegraph-devel/main.log Error: The following dependencies failed to build: py-py2app-devel py-modulegraph-devel Error: Status 1 encountered during processing. To report a bug, see <http://guide.macports.org/#project.tickets> I attempted to correct the issue by entering the following: port -f activate py-modulegraph-devel But it returned this error: Warning: Failed to open Portfile from registry for py-modulegraph-devel @0.7.2_0 ---> Activating py-modulegraph-devel Error: port activate failed: sqlite error: attempt to write a readonly database (8) This is as far as I have got with resolving this issue so far. All help and guidance will be greatly appreciated. Kevin Rapley

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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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2to3 conversion
by Zubin Mithra July 1, 2011

July 1, 2011

Hey everyone, I was running 2to3 on a particular file and I got the following traceback( http://paste.pocoo.org/show/223468/). The file which I was attempting to convert can be viewed here( http://paste.pocoo.org/show/223469/). Any pointers on what needs to be done? Thanks in advance, Zubin

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sftp get single file
by Matt Herzog June 22, 2011

June 22, 2011

Hello All. I need to use paramiko to sftp get a single file from a remote server. The remote file's base name will be today's date (%Y%m%d) dot tab. I need help joining the today with the .tab extension. Do I need globbing? example: 20090716.tab #!/usr/bin/env python import paramiko import glob import os import time hostname = 'sftp.booboo.com' port = 22 username = 'booboo' password = '07N4219?' # glob_pattern='*.tab' today = time.strftime("%Y%m%d") remotepath = today.tab localpath = '/home/data/text' if __name__ == "__main__": t = paramiko.Transport((hostname, port)) t.connect(username=username, password=password) sftp = paramiko.SFTPClient.from_transport(t) sftp.get(remotepath, localpath) t.close() -- I fear you speak upon the rack, Where men enforced do speak anything. - William Shakespeare

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Plotting a Linear Equation
by Corey Richardson April 21, 2011

April 21, 2011

Hello tutors. Probably the wrong mailing list, but someone might know. I want to use matplotlib (or similar) to plot an equation in slope-intercept (y=mx+b) or standard form (Ax + By = C). As far as I've read and tested, you can only plot with a series of points. I could make two points out of those manually, but I was wondering if anyone knew of an easier way. Thanks.

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Multiples python files
by Christopher Brookes March 1, 2011

March 1, 2011

Hi, first sorry for my poor english, i'm a french guy, i'm trying to make the best :( I would like to split my python script into multiples files. I want : A file which contains only class creations and methods, A file with some personals functions And a main.py which is the main script. But i'm getting some problems In class creation file, i've a init method which create a character (it works). They are created in main.py like this : herosAll = [ Character(1,"Antaa","Soldat moins fort",15,5,8), Character(2,"Klaitos","Soldat moins fort",15,5,8)] But when i want to display all information about my character with : class Character(): def DisplayAll(): print ('There is', Character.CharacterCount, 'heros') for heros in herosAll: heros.DisplayCharacterInfos() I'm getting : Traceback (most recent call last): File "main.py", line 28, in <module> Character.DisplayAll() File "/home/christopher/class_creation.py", line 53, in DisplayAll for heros in herosAll: NameError: global name 'herosAll' is not defined I know the source of the problem. The list herosAll is declared in main.py so he can't access to it. But i'm stuck here. How can he get it ? Have I to append the list in the init method ? Thank you for ready. -- Brookes Christopher.

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Socket and Changing IP's
by Jacob Bender March 1, 2011

March 1, 2011

Tutors, I was looking into network programming, and I came across a problem. Socket programs need an IP address to function correctly, right? Well, IP addresses are always changing, so how should I go about making sockets that will work for an extended period of time? Thanks in advance!

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Timer with exe command
by Kaden McLaws Feb. 28, 2011

Feb. 28, 2011

I would like to set up the following using python: A timer that is activated when a user logs on to our computer, then shuts the computer down when the timer runs out (no matter what, ending all programs). First, a raw input is used, so that if you know the password, you may shut off the timer (set for 90 mins). Otherwise, it is activated. This is a timer to be used so (anonymous) can only spend 90 mins playing Modern Warfare, and not hours upon end like he does. I was also wondering about parsing. It would be effective if the last time the timer activated was recorded in a txt file, logged, so that the program can check and ensure that the last time the timer ended was at least 12 hours ago, so the computer just isnt turned right back on for another 90 mins repeatedly.Is there also a way to run the python hidden in the background so he cannot just figure out how to close it?If you aren't sure off all the details, email me back. Thanks for helping me save (anonymous) from wasting too much time on MW2! :)

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string conversion
by Robert Clement Feb. 28, 2011

Feb. 28, 2011

Hi I have a wxpython control in which users are intended to enter control characters used to define binary string delimiters, eg. '\xBA\xBA' or '\t\r\n' . The string returned by the control is a unicode version of the string entered by the user, eg. u'\\xBA\\xBA' or u'\\t\\r\\n' . I would like to be able retrieve the original string containing the escaped control characters or hex values so that I can assign it to a variable to be used to split the binary string. Does anyone know of a way this can be achieved? Thanks Rob -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.

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