PyOhio (July 30-31) Call for Proposals; due June 3
PyOhio 2011, the fourth annual Python programming conference for Ohio and the surrounding region, will take place Saturday-Sunday, July 30-31, 2011 at the Ohio State University in Columbus, Ohio. A variety of activities are planned, including tutorials, scheduled talks, Lightning Talks, Open Spaces and Sprints. PyOhio invites all interested people to submit proposals for scheduled talks, tutorials, and panels. All topics of interest to Python programmers will be considered. Standard presentation slots will be 40 minutes plus a 10 minute question-and-answer period. PyOhio is a great venue to get word out about your favorite Python library and how you use it, talk about how Python is used in your company, or practice your speaking in front of a welcoming audience. PyOhio is especially interested in hosting a Beginner’s Track for those new to Python or new to programming in general. If your proposal would be suitable for inclusion in a Beginner’s Track, please indicate so. Organizers will work with speakers and instructors in the Beginner’s Track to help them coordinate their talks/tutorials into a smooth, coherent learning curve for new Python users. To ensure that you provide all necessary information, please use the submission template provided below. If organizing a panel, please confirm all panelists’ intention to participate before submitting your proposal. PyOhio may record presentations for later release over the web. Presenters will need to sign a release of recording rights to PyOhio; see http://wiki.python.org/moin/PyOhio/RecordingRelease All proposals should be emailed to c...@pyohio.org for review. Please submit proposals by Friday, June 3, 2011. Accepted speakers will be notified by June 17. You can read more about the conference at http://pyohio.org. If you have questions about proposals, please email c...@pyohio.org. You can also contact the PyOhio organizers at pyohio-organiz...@python.org. The template can be downloaded here: http://bit.ly/lJAACo [pyohio.org] -- - Catherine http://catherinedevlin.blogspot.com -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations/
Re: ElementTree XML parsing problem
Hegedüs Ervin, 27.04.2011 21:33: hello, I'm using ElementTree to parse an XML file, but it stops at the second record (id = 002), which contains a non-standard ascii character, ä. Here's the XML: ?xml version=1.0? snapshot time=Mon Apr 25 08:47:23 PDT 2011 records record id=001 education=High School employment=7 yrs / record id=002 education=Universität Bremen employment=3 years / record id=003 education=River College employment=5 yrs / /records /snapshot The complaint offered up by the parser is I've checked this xml with your script, I think your locales settings are not good. $ ./parse.py XML file: test.xml 001 High School 002 Universität Bremen 003 River College (name of xml file is test.xml) So, I started change the codepage mark of xml: ?xml version=1.0 encoding=UTF-8 ? - same result ?xml version=1.0 encoding=ISO-8859-2 ? - same result ?xml version=1.0 encoding=ISO-8859-1 ? - same result You probably changed this in an editor that supports XML and thus saves the file in the declared encoding. Switching between the three by simply changing the first line (the XML declaration) and not adapting the encoding of the document itself would otherwise not yield the same result for the document given above. Stefan -- http://mail.python.org/mailman/listinfo/python-list
Re: Access violation reading 0x00000010
libcommon = CDLL(c:\libcommon-0.dll, RTLD_GLOBAL) libcommon.SIM_init() - This is the invoking. thanks, yuanzheng. 2011/4/28 Chris Angelico ros...@gmail.com On Thu, Apr 28, 2011 at 1:00 PM, yuan zheng tsinghuayua...@gmail.com wrote: Hi, everyone. I have a question when I invoke an api which is included a library open by CDLL. And then it will prompt the follow error: How are you invoking it? Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Access violation reading 0x00000010
On Thu, Apr 28, 2011 at 4:01 PM, yuan zheng tsinghuayua...@gmail.com wrote: libcommon = CDLL(c:\libcommon-0.dll, RTLD_GLOBAL) libcommon.SIM_init() - This is the invoking. When you have a backslash in a literal string, you need to double it: libcommon = CDLL(c:\\libcommon-0.dll, RTLD_GLOBAL) I don't know if that's your problem, but it could be! Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list
Re: ElementTree XML parsing problem
hello, On Thu, Apr 28, 2011 at 07:57:28AM +0200, Stefan Behnel wrote: So, I started change the codepage mark of xml: ?xml version=1.0 encoding=UTF-8 ? - same result ?xml version=1.0 encoding=ISO-8859-2 ? - same result ?xml version=1.0 encoding=ISO-8859-1 ? - same result You probably changed this in an editor that supports XML and thus saves the file in the declared encoding. no. I've saved the XML as UTF8, and didn't change the _file_ encoding - just modified the XML header, nothing else... (I'm using Geany - it doesn't realize what user wrote in file, just can save file as another encodign, when user choose one) Switching between the three by simply changing the first line (the XML declaration) and not adapting the encoding of the document itself would otherwise not yield the same result for the document given above. yes, that's what I wrote exactly. a. -- http://mail.python.org/mailman/listinfo/python-list
Re: Have you read the Python docs lately?
Raymond Hettinger pyt...@rcn.com writes: A number of developers have been working on adding examples and useful advice to the docs. To sharpen your skills, here are some pieces of recommended reading: Thanks, those are nice. The logging one looks especially useful. The module always looked very confusing to me (too Java-like), and I've dreaded the day when I might have to figure out how to use it instead of my own ad-hoc logging. I can sleep better now ;-). -- http://mail.python.org/mailman/listinfo/python-list
Re: Access violation reading 0x00000010
Sorry , the path is just an example. This is not the question I think. Because there is lots of api in libcommon-0.dll, and there is no fault when invoking other api, such as libcommon.SIM_start().. It's just fault when invoking this api - SIM_init(). So I wanna which situation would lead to this error: -- WindowsError: exception: access violation reading 0x0010 -- thanks, yuanzheng. 2011/4/28 Chris Angelico ros...@gmail.com On Thu, Apr 28, 2011 at 4:01 PM, yuan zheng tsinghuayua...@gmail.com wrote: libcommon = CDLL(c:\libcommon-0.dll, RTLD_GLOBAL) libcommon.SIM_init() - This is the invoking. When you have a backslash in a literal string, you need to double it: libcommon = CDLL(c:\\libcommon-0.dll, RTLD_GLOBAL) I don't know if that's your problem, but it could be! Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Have you read the Python docs lately?
On 4/27/2011 7:40 PM, Ben Finney wrote: http://docs.python.org/dev/howto/logging.html This one in particular was sorely needed, especially its early if-then discussion of whether to use ‘logging’ at all. Thanks very much to Vinay Sajip. Yes, he has been working pretty steadily for some months to improve the tests, code, and docs. -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: Reliably call code after object no longer exists or is unreachable?
Jack Bates wrote: Python's __del__ or destructor method works (above) - but only in the absence of reference cycles (below). An object, with a __del__ method, in a reference cycle, causes all objects in the cycle to be uncollectable. Store a weak reference to the object somewhere with a callback. This should work even in the presence of cycles, as long as the weak reference itself isn't part of the cycle. -- Greg -- http://mail.python.org/mailman/listinfo/python-list
argparse parser stores lists instead of strings
I've set up groups of arguments for a script I'm writing, and any time I
give an argument a value, it gets stored as a list instead of a string,
even if I explicitly tell it to store a string. Arguments declared with
other types (e.g. float, int) and default values are stored as expected.
For example:
vidin_args=parser.add_argument_group('Video Input Options', 'Various
options that control how the video file is demuxed/decoded.')
vidin_args.add_argument('-m', dest='vmode', nargs=1, type=str,
metavar='video_mode', choices=['ntsc', 'pal', 'film', 'ivtc'],
default='ntsc', help='Valid values are ntsc, pal, film and ivtc.')
...more arguments...
opts=parser.parse_args()
If I assign a value on the command line (e.g. -m pal), opts.vmode is a
list, otherwise it's a string. This is pretty bad since I can't know
whether to get opts.vmode or opts.vmode[0] later in the script. I could
loop through all the options and convert each option to a string, but
that's not really something I want to do, especially if I start adding
more options.
I'm pretty new to Python, and I might have missed something, but I have
been looking!
In case it matters, I'm learning Python 3.2 and have no intention of
using older code (once I have one version of Python covered, then I'll
look into making code that's compatible with 2.x if I have to).
--
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Re: unpickling derived LogRecord in python 2.7 from python2.6
Vinay Sajip wrote: On Apr 27, 5:41 pm, Peter Otten __pete...@web.de wrote: The Problem is that as of Python 2.7logging.LogRecord has become a newstyle class which is pickled/unpickled differently. I don't know if there is an official way to do the conversion, but here's what I've hacked up. The script can read pickles written with 2.6 in 2.7, but not the other way round. [code snipped] I don't know about official, but another way of doing this is to pickle just the LogRecord's __dict__ and send that over the wire. The logging package contains a function makeLogRecord(d) where d is a dict. You are right, my approach is too complicated and only needed when the OP cannot modify the sending script -- which is unlikely. This is the approach used by the examples in the library documentation which pickle events for sending across a network: http://docs.python.org/howto/logging-cookbook.html#sending-and-receiving- logging-events-across-a-network The built-in SocketHandler pickles the LogRecord's __dict__ rather than the LogRecord itself, precisely because of the improved interoperability over pickling the instance directly. As a minimal change ensuring that the logging.LogRecord subclass used by the OP is a newstyle class in 2.6 with class LogRecord(logging.LogRecord, object): #... should work, too. -- http://mail.python.org/mailman/listinfo/python-list
Re: Access violation reading 0x00000010
I have found my question's answer. The fault is sourced from the implement of SIM_init(). Thanks a lot. thanks, yuanzheng. 2011/4/28 yuan zheng tsinghuayua...@gmail.com Sorry , the path is just an example. This is not the question I think. Because there is lots of api in libcommon-0.dll, and there is no fault when invoking other api, such as libcommon.SIM_start().. It's just fault when invoking this api - SIM_init(). So I wanna which situation would lead to this error: -- WindowsError: exception: access violation reading 0x0010 -- thanks, yuanzheng. 2011/4/28 Chris Angelico ros...@gmail.com On Thu, Apr 28, 2011 at 4:01 PM, yuan zheng tsinghuayua...@gmail.com wrote: libcommon = CDLL(c:\libcommon-0.dll, RTLD_GLOBAL) libcommon.SIM_init() - This is the invoking. When you have a backslash in a literal string, you need to double it: libcommon = CDLL(c:\\libcommon-0.dll, RTLD_GLOBAL) I don't know if that's your problem, but it could be! Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: argparse parser stores lists instead of strings
Andrew Berg wrote:
I've set up groups of arguments for a script I'm writing, and any time I
give an argument a value, it gets stored as a list instead of a string,
even if I explicitly tell it to store a string. Arguments declared with
other types (e.g. float, int) and default values are stored as expected.
For example:
vidin_args=parser.add_argument_group('Video Input Options', 'Various
options that control how the video file is demuxed/decoded.')
vidin_args.add_argument('-m', dest='vmode', nargs=1, type=str,
metavar='video_mode', choices=['ntsc', 'pal', 'film', 'ivtc'],
default='ntsc', help='Valid values are ntsc, pal, film and ivtc.')
...more arguments...
opts=parser.parse_args()
If I assign a value on the command line (e.g. -m pal), opts.vmode is a
list, otherwise it's a string. This is pretty bad since I can't know
whether to get opts.vmode or opts.vmode[0] later in the script. I could
loop through all the options and convert each option to a string, but
that's not really something I want to do, especially if I start adding
more options.
I'm pretty new to Python, and I might have missed something, but I have
been looking!
http://docs.python.org/py3k/library/argparse.html#nargs
Note that nargs=1 produces a list of one item. This is different from the
default, in which the item is produced by itself.
So just omit 'nargs=1' from the add_argument() call.
In case it matters, I'm learning Python 3.2 and have no intention of
using older code (once I have one version of Python covered, then I'll
look into making code that's compatible with 2.x if I have to).
--
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Re: use of index (beginner's question)
On Apr 28, 2:45 am, Chris Angelico ros...@gmail.com wrote: Incidentally, you're allowed to put the comma on the last item too: lists = [ ['pig', 'horse', 'moose'], ['62327', '49123', '79115'], ] Often makes for easier maintenance, especially when you append array/list elements. Chris Angelico I did not know this. Very useful! Iain -- http://mail.python.org/mailman/listinfo/python-list
Re: argparse parser stores lists instead of strings
En Thu, 28 Apr 2011 04:24:46 -0300, Andrew Berg
bahamutzero8...@gmail.com escribió:
I've set up groups of arguments for a script I'm writing, and any time I
give an argument a value, it gets stored as a list instead of a string,
even if I explicitly tell it to store a string. Arguments declared with
other types (e.g. float, int) and default values are stored as expected.
For example:
vidin_args=parser.add_argument_group('Video Input Options', 'Various
options that control how the video file is demuxed/decoded.')
vidin_args.add_argument('-m', dest='vmode', nargs=1, type=str,
metavar='video_mode', choices=['ntsc', 'pal', 'film', 'ivtc'],
default='ntsc', help='Valid values are ntsc, pal, film and
ivtc.')
...more arguments...
opts=parser.parse_args()
If I assign a value on the command line (e.g. -m pal), opts.vmode is a
list, otherwise it's a string. This is pretty bad since I can't know
whether to get opts.vmode or opts.vmode[0] later in the script. I could
loop through all the options and convert each option to a string, but
that's not really something I want to do, especially if I start adding
more options.
That's because of nargs=1. From the argparse documentation: [1]
Note that nargs=1 produces a list of one item. This is different from the
default, in which the item is produced by itself.
So, just remove nargs=1 from add_argument()
[1] http://docs.python.org/py3k/library/argparse.html#nargs
--
Gabriel Genellina
--
http://mail.python.org/mailman/listinfo/python-list
Re: Access violation reading 0x00000010
En Thu, 28 Apr 2011 03:35:48 -0300, yuan zheng tsinghuayua...@gmail.com escribió: Sorry , the path is just an example. This is not the question I think. Because there is lots of api in libcommon-0.dll, and there is no fault when invoking other api, such as libcommon.SIM_start().. It's just fault when invoking this api - SIM_init(). So I wanna which situation would lead to this error: -- WindowsError: exception: access violation reading 0x0010 -- On Thu, Apr 28, 2011 at 4:01 PM, yuan zheng tsinghuayua...@gmail.com wrote: libcommon = CDLL(c:\libcommon-0.dll, RTLD_GLOBAL) libcommon.SIM_init() - This is the invoking. It's hard to guess, but if you get an access violation just from those two lines of code, I'd say the problem is inside SIM_init() itself. It may be attempting to dereference a NULL pointer: accessing a field inside a struct, or calling a virtual function from a NULL object... Also, make sure CDLL is the right choice; it implies a prototype like this: int cdecl SIM_INIT(void); -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Spurious character in IOError exception
When I correctly trap an IOError a spurious u' appears in the file path in the exception message : The path used in the code is correct i.e. /home/myfile But the error message says : [Errno 2] No such file or directory: u'/home/myfile' I am simply doing except IOError, e: print str(e) Any ideas where the 'u is coming from? This is python 2.4.1 -- http://mail.python.org/mailman/listinfo/python-list
Re: How to upload a file
En Wed, 27 Apr 2011 11:14:54 -0300, Torsten Bronger bron...@physik.rwth-aachen.de escribió: Hallöchen! I'm skimming through the various recipies for uploading a file via HTTP. Unfortunately, all of them are awkward but also rather old. (See for example http://stackoverflow.com/questions/68477/send-file-using-post-from-a-python-script) In my module, I do my HTTP request like this: opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cookielib.CookieJar())) opener.open(url, urllib.urlencode(data, doseq=True)) Well, and now I'd also like to include a file upload to the POST data. The solution should use urllib2, otherwise I'd have to change most of my existing code. If you now say Torsten, unfortunately it *is* so complicated I'll jump through the hoops, but I'd love to hear that with Python 2.6.5 there's an easier way. ;-) This particular battery isn't included (yet - see http://bugs.python.org/issue3244) but this little library may help: https://bitbucket.org/chrisatlee/poster -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Re: Spurious character in IOError exception
loial wrote: When I correctly trap an IOError a spurious u' appears in the file path in the exception message : The path used in the code is correct i.e. /home/myfile But the error message says : [Errno 2] No such file or directory: u'/home/myfile' I am simply doing except IOError, e: print str(e) Any ideas where the 'u is coming from? This is python 2.4.1 The filename does not appear directly in the error message, it is first converted by repr(). This ensures that (1) the error message will consist only of ascii characters (2) the filename can reliably reconstructed from the message try: open(äöü) ... except IOError, e: print e ... [Errno 2] No such file or directory: '\xc3\xa4\xc3\xb6\xc3\xbc' but the output may puzzle end users. The u'...' in your case means that you passed a unicode string to the open(...) function. try: open(uäöü) ... except IOError, e: print e ... [Errno 2] No such file or directory: u'\xe4\xf6\xfc' If you are sure that the output device supports unicode output (i. e. has a known encoding and can display the characters in your filename) you can build a friendlier message try: open(uäöü) ... except IOError, e: print u[Errno %d] %s: %s % (e.errno, e.strerror, e.filename) ... [Errno 2] No such file or directory: äöü Be aware though that some problems become near-impossible to detect that way: try: open(uäöü\n) # note the trailing newline ... except IOError, e: print u[Errno %d] %s: %s % (e.errno, e.strerror, e.filename) ... [Errno 2] No such file or directory: äöü -- http://mail.python.org/mailman/listinfo/python-list
Re: use of index (beginner's question)
On Apr 28, 5:32 am, Algis Kabaila akaba...@pcug.org.au wrote: On Thursday 28 April 2011 11:23:51 Thomas 'PointedEars' Lahn wrote: Chris Angelico wrote: Rusty Scalf wrote: list1 = ['pig', 'horse', 'moose'] list2 = ['62327', '49123', '79115'] n = 2 s2 = list + `n` list + 'n' 'listn' And IMHO you did not want that, did you? OldAl. -- Algishttp://akabaila.pcug.org.au/StructuralAnalysis.pdf It will not be 'listn' it will be 'list2'. He is using back ticks ` which translates the n into its value 2. Granted it is not very readable (as it can easily be mistaken for a single quote depending on the font your using). It would be better written as 'list%s' %n -- http://mail.python.org/mailman/listinfo/python-list
Need your help
Hi friends: Here I need some help. #encoding=utf-8 #moudle a.py def a(): print function a! #encoding=utf-8 #moudle b.py def b(): print function b! #encoding=utf-8 #moudle c.py import a import b def c(): a.a() b.b() Here in function c,How can i record all the information printed by a and b with out modifying moudle a and b? I want to output all the printed information into a text file. Need your help, thanks a lot! Best Regards 2011-04-28 Kerry Wang-- http://mail.python.org/mailman/listinfo/python-list
Re: Need your help
On Wed, Apr 27, 2011 at 10:38 PM, 1011_wxy 1011_...@163.com wrote:
Hi friends:
Here I need some help.
#encoding=utf-8
#moudle a.py
def a():
print function a!
#encoding=utf-8
#moudle b.py
def b():
print function b!
#encoding=utf-8
#moudle c.py
import a
import b
def c():
a.a()
b.b()
Here in function c,How can i record all the information printed by a and b
with out modifying moudle a and b?
I want to output all the printed information into a text file.
Need your help, thanks a lot!
import a, b, sys
def c():
orig_stdout = sys.stdout
sys.stdout = open('my_log_file.log', 'w')
a.a()
b.b()
sys.stdout.close()
sys.stdout = orig_stdout
Someone may have written a with-statement context manager that
abstracts away the swapping.
Cheers,
Chris
--
http://rebertia.com
--
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Re: Need your help
hello, Here I need some help. #encoding=utf-8 #moudle a.py def a(): print function a! #encoding=utf-8 #moudle b.py def b(): print function b! #encoding=utf-8 #moudle c.py import a import b def c(): a.a() b.b() Here in function c,How can i record all the information printed by a and b with out modifying moudle a and b? I want to output all the printed information into a text file. Need your help, thanks a lot! sounds you want something like this: #!/usr/bin/python import a import b import sys import StringIO output = StringIO.StringIO() def c(): # save default stdout tout = sys.stdout # redirect stdout to StringIO object sys.stdout = output # a.a() prints their output to StringIO object a.a() # back up default stdout sys.stdout = tout # print StringIO object value print retval:, output.getvalue() c() a. -- http://mail.python.org/mailman/listinfo/python-list
Re: Need your help
hello, On Thu, Apr 28, 2011 at 01:20:16PM +0200, Ervin Hegedüs wrote: #!/usr/bin/python import a import b import sys import StringIO output = StringIO.StringIO() def c(): # save default stdout tout = sys.stdout # redirect stdout to StringIO object sys.stdout = output # a.a() prints their output to StringIO object a.a() # back up default stdout sys.stdout = tout # print StringIO object value print retval:, output.getvalue() c() sorry, this is a littlebit more abstact example, it gives a StringIO object, instead of write to a file - of course, you can do what you want with that string... a. -- http://mail.python.org/mailman/listinfo/python-list
Re: Need your help
1011_wxy wrote: Hi friends: Here I need some help. #encoding=utf-8 #moudle a.py def a(): print function a! #encoding=utf-8 #moudle b.py def b(): print function b! #encoding=utf-8 #moudle c.py import a import b def c(): a.a() b.b() Here in function c,How can i record all the information printed by a and b with out modifying moudle a and b? I want to output all the printed information into a text file. Need your help, thanks a lot! Best Regards 2011-04-28 Kerry Wang Hi, python c.py afile.log JM -- http://mail.python.org/mailman/listinfo/python-list
High respected career - Careers in next month
Potential income in Management careers. Work in Management careers. Visit: http://managementjobs.webs.com/index.htm http://jobscore.webs.com/executivemanager.htm Careers for Management - Careers in next month http://employmentsmanagement.blogspot.com/ http://rojgars1.webs.com/gov.htm -- http://mail.python.org/mailman/listinfo/python-list
回复: Re: Need your help
Hi JM: python c.py afile.log could you pls give me the whole example? I am so sorry that I am a beginner in Python. 2011-04-28 1011_wxy 发件人: Jean-Michel Pichavant jeanmic...@sequans.com 发送时间: 2011-04-28 20:42 主 题: Re: Need your help 收件人: 1011_wxy 1011_...@163.com 抄 送: python-list@python.org python-list@python.org 1011_wxy wrote: Hi friends: Here I need some help. #encoding=utf-8 #moudle a.py def a(): print function a! #encoding=utf-8 #moudle b.py def b(): print function b! #encoding=utf-8 #moudle c.py import a import b def c(): a.a() b.b() Here in function c,How can i record all the information printed by a and b with out modifying moudle a and b? I want to output all the printed information into a text file. Need your help, thanks a lot! Best Regards 2011-04-28 Kerry Wang Hi, python c.py afile.log JM -- http://mail.python.org/mailman/listinfo/python-list
Re: 回复: Re: Need your help
1011_wxy wrote: Hi JM: *python c.py afile.log* could you pls give me the whole example? I am so sorry that I am a beginner in Python. Your module a and b that you cannot modify given your original description, are printing data using the print statement. That means these module only intend to print the data on the standard output (aka stdout, your screen by default). If you want to print the data in a file, then you have to make stdout that file. 2 possible way have been provided: 1/ within the c.py file, redirect sys.stdout to a file (see Chris Rebert's answer) 2/ use the system command line to redirect stdout to a file. In any unix system, you can redirect stdout to a file( instead of the screen) that way: echo Hello world afile.txt It works for any command, including python c.py afile.txt That will execute you c.py file writing everything into afile.txt instead of your display. JM -- http://mail.python.org/mailman/listinfo/python-list
Re: Need your help
Am 28.04.2011 13:14, schrieb Chris Rebert:
import a, b, sys
def c():
orig_stdout = sys.stdout
sys.stdout = open('my_log_file.log', 'w')
a.a()
b.b()
sys.stdout.close()
sys.stdout = orig_stdout
Someone may have written a with-statement context manager that
abstracts away the swapping.
@contextlib.contextmanager
def swap_stdout(target):
orig_stdout = sys.stdout
sys.stdout = target
try:
yield target
finally:
sys.stdout = orig_stdout
In this case, I can use all kinds of files (open() files, StringIO
objects etc.), and can re-use them if necessary, in order to
prepend/append data.
Closing can happen additionally, if the user wants.
Thomas
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Read-write lock for Python
Hi all, I currently find myself needing a Python read-write lock. I note that there is none in the standard library, but googling python read-write lock quickly produced 6 different competing examples, including two languishing patch proposals for the standard library. I can always pick a random one and hope for the best, but I was hoping someone here might have a tip for one that has been used and debugged and is likely to work. Regards, Geoff Bache -- http://mail.python.org/mailman/listinfo/python-list
Re: Read-write lock for Python
Geoff Bache wrote: Hi all, I currently find myself needing a Python read-write lock. I note that there is none in the standard library, but googling python read-write lock quickly produced 6 different competing examples, including two languishing patch proposals for the standard library. I can always pick a random one and hope for the best, but I was hoping someone here might have a tip for one that has been used and debugged and is likely to work. Regards, Geoff Bache What about http://docs.python.org/library/threading.html#lock-objects ? JM -- http://mail.python.org/mailman/listinfo/python-list
Re: Python IDE/text-editor
In article mailman.511.1303137613.9059.python-l...@python.org, Alec Taylor alec.tayl...@gmail.com wrote: Geany I've tried in the past, it's really buggy on my home computer and at Uni... however from my phone it works wonderfully! (Use it for C++ projects on Rhobuntu) Eric 4 was suggested to me on the #python channel on Freenode... however I've never been able to get it compiled/working. Too many dependencies I'm guessing... PTK looks great, and does everything I want (from screenshots). Unfortunately, it doesn't run on my system; Win7 x64, Python 2.7.1 x64, WxPython 2.8 x64. Install ran as admin. Emacs and vim still seem like good alternatives, when I get the time. However, currently have 3 assignments to start and finish so would like a simple Notepad2 with python interpreter attached (and keyboard shortcut to run script) type program. Please continue recommending Thanks, Alec Taylor You will never be satisfied, until you've written something yourself. Start writing now. A friend of mine started writing in 1983, and since 1985 I'm a happy user. The only language that is a candidate to write in is C, however. Groetjes Albert -- -- Albert van der Horst, UTRECHT,THE NETHERLANDS Economic growth -- being exponential -- ultimately falters. albert@spearc.xs4all.nl =n http://home.hccnet.nl/a.w.m.van.der.horst -- http://mail.python.org/mailman/listinfo/python-list
Re: Equivalent code to the bool() built-in function
In article iok5tg$svv$1...@reader1.panix.com, Grant Edwards invalid@invalid.invalid wrote: On Tue, Apr 19, 2011 at 7:09 AM, Christian Heimes li...@cheimes.de wrote: Am 18.04.2011 21:58, schrieb John Nagle: ?? ?? This is typical for languages which backed into a bool type, rather than having one designed in. ??The usual result is a boolean type with numerical semantics, like ?? True + True 2 I find the behavior rather useful. It allows multi-xor tests like: if a + b + c + d != 1: ?? ??raise ValueError(Exactly one of a, b, c or d must be true.) I guess I never thought about it, but there isn't an 'xor' operator to go along with 'or' and 'and'. Must not be something I need very often. There is. applied to booleans is xor. -- Grant Edwards grant.b.edwardsYow! I am having FUN... at I wonder if it's NET FUN or gmail.comGROSS FUN? -- -- Albert van der Horst, UTRECHT,THE NETHERLANDS Economic growth -- being exponential -- ultimately falters. albert@spearc.xs4all.nl =n http://home.hccnet.nl/a.w.m.van.der.horst -- http://mail.python.org/mailman/listinfo/python-list
Re: Equivalent code to the bool() built-in function
In article 9142usf51...@mid.individual.net, Gregory Ewing greg.ew...@canterbury.ac.nz wrote: Chris Angelico wrote: Remind me some day to finish work on my ultimate programming language, which starts out with a clean slate and lets the programmer define his own operators and everything. Didn't someone already do that and call it lisp? :-) Lisp is betrayed by its brackets. He wants Forth. -- Greg Groetjes Albert -- -- Albert van der Horst, UTRECHT,THE NETHERLANDS Economic growth -- being exponential -- ultimately falters. albert@spearc.xs4all.nl =n http://home.hccnet.nl/a.w.m.van.der.horst -- http://mail.python.org/mailman/listinfo/python-list
socket.gethostbyaddr() wrongly returning a DNS CNAME as the 'primary' hostname
Python 2.7.1 (perhaps others)
I believe this is a bug. Comments?
Docs state: Return a triple (hostname, aliaslist, ipaddrlist)
where hostname is the primary host name responding to the
given ip_address, aliaslist is a (possibly empty) list of
alternative host names for the same address, and ipaddrlist
is a list of IPv4/v6 addresses for the same interface on the
same host (most likely containing only a single address).
my-dns-cname.our.org is a CNAME record for primary.our.org
primary.our.org has IP address xx.xx.xx.xx
import socket
socket.gethostbyaddr('xx.xx.xx.xx')
returns:
('my-dns-cname.our.org', ['primary.our.org'], ['xx.xx.xx.xx'])
--
http://mail.python.org/mailman/listinfo/python-list
NaN
There's a big discussion going on at python-dev and python-ideas about NaN (not-a-number, from IEEE 754). I haven't really gotten into any scientific computing or numeric programming so I have never knowingly dealt with NaN. However, I have read the discussions and several things are not clear: 1. Why is NaN not an exception? (not why not change it to one? Changing it now would probably break stuff.) 2. What are the use cases for NaN? Looks like it gets used a lot as a numeric (float?) object with non-value. Any clarification would be really helpful. Thanks! -eric -- http://mail.python.org/mailman/listinfo/python-list
IDLE lost from Windows menu !
I have lost the convenient feature that to edit a .py file I could right-click on the file name and reach the menu item Edit with IDLE. The workaround is not hard, but it wouild be nice to get this feature back. It happened when I was mungeing around and downloaded Python 2.3.3 in addition to Python 2.71, and got into trojuble uintil I discovered that I was involuntarily RUNNING the older version. So I cleaned it out, but still I have this aftermath. Is there a Windows guru out there who can tell be how to add to the right-click menu clicking on myfile.py? Uncle Ben -- http://mail.python.org/mailman/listinfo/python-list
multiprocessing: file-like object
I've been having issues with getting a file-like object to work with multiprocessing. Since the details are quite lengthy, I've posted them on stackoverflow here: http://stackoverflow.com/questions/5821880/python-multiprocessing-synchronizing-file-like-object I hope I'm not being super rude by cross-posting, but I thought some of you would be interested in the question, and I'd be delighted to get some ideas. -- http://mail.python.org/mailman/listinfo/python-list
Re: Have you read the Python docs lately?
On Apr 27, 11:28 pm, Paul Rubin no.em...@nospam.invalid wrote: Raymond Hettinger pyt...@rcn.com writes: A number of developers have been working on adding examples and useful advice to the docs. To sharpen your skills, here are some pieces of recommended reading: Thanks, those are nice. The logging one looks especially useful. The module always looked very confusing to me (too Java-like), and I've dreaded the day when I might have to figure out how to use it instead of my own ad-hoc logging. I can sleep better now ;-). Vinay put also put together a logging cookbook: http://docs.python.org/howto/logging-cookbook.html Raymond -- http://mail.python.org/mailman/listinfo/python-list
Re: Equivalent code to the bool() built-in function
I'm not not touching you! -- http://mail.python.org/mailman/listinfo/python-list
Re: NaN
On Thu, Apr 28, 2011 at 9:21 AM, Eric Snow ericsnowcurren...@gmail.com wrote: There's a big discussion going on at python-dev and python-ideas about NaN (not-a-number, from IEEE 754). I haven't really gotten into any scientific computing or numeric programming so I have never knowingly dealt with NaN. However, I have read the discussions and several things are not clear: 1. Why is NaN not an exception? (not why not change it to one? Changing it now would probably break stuff.) Most things that would produce NaN [e.g. x/0, sqrt(-abs(x))] in lower-level languages do produce exceptions in Python. If you encounter a NaN in Python, it was probably either explicitly created or came from a C extension library. It's basically an abstraction leaked through from C/hardware for compatibility. 2. What are the use cases for NaN? Looks like it gets used a lot as a numeric (float?) object with non-value. FWICT, it's useful in lower-level languages (which typically lack exceptions and often lack nice ways of returning multiple values from a function) as a convenient way of signaling a mathematical error. It also lets some calculations continue to limp along (albeit with a NaN result) after an error rather than forcing the probably slower explicit handling of the error at the time of its occurrence. And it's used to represent missing numeric data values, sort of like a numerical None/Null: How much does the truck weigh? NaN (i.e. No idea; we haven't put it on the scale yet). Cheers, Chris -- http://rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Composition instead of inheritance
For anybody interested in composition instead of multiple inheritance, I have posted this recipe on ActiveState (for python 2.6/7, not 3.x): http://code.activestate.com/recipes/577658-composition-of-classes-instead-of-multiple-inherit/ Comments welcome! ~Ethan~ -- http://mail.python.org/mailman/listinfo/python-list
Re: Python IDE/text-editor
Your probably right. I suppose I'll just wait till I finish my fooIDE project On Fri, Apr 29, 2011 at 2:21 AM, Albert van der Horst alb...@spenarnc.xs4all.nl wrote: In article mailman.511.1303137613.9059.python-l...@python.org, Alec Taylor alec.tayl...@gmail.com wrote: Geany I've tried in the past, it's really buggy on my home computer and at Uni... however from my phone it works wonderfully! (Use it for C++ projects on Rhobuntu) Eric 4 was suggested to me on the #python channel on Freenode... however I've never been able to get it compiled/working. Too many dependencies I'm guessing... PTK looks great, and does everything I want (from screenshots). Unfortunately, it doesn't run on my system; Win7 x64, Python 2.7.1 x64, WxPython 2.8 x64. Install ran as admin. Emacs and vim still seem like good alternatives, when I get the time. However, currently have 3 assignments to start and finish so would like a simple Notepad2 with python interpreter attached (and keyboard shortcut to run script) type program. Please continue recommending Thanks, Alec Taylor You will never be satisfied, until you've written something yourself. Start writing now. A friend of mine started writing in 1983, and since 1985 I'm a happy user. The only language that is a candidate to write in is C, however. Groetjes Albert -- -- Albert van der Horst, UTRECHT,THE NETHERLANDS Economic growth -- being exponential -- ultimately falters. albert@spearc.xs4all.nl =n http://home.hccnet.nl/a.w.m.van.der.horst -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: use of index (beginner's question) (Iain King)
Envoyé de mon iPad Le 2011-04-28 à 4:55, python-list-requ...@python.org a écrit : Send Python-list mailing list submissions to python-list@python.org To subscribe or unsubscribe via the World Wide Web, visit http://mail.python.org/mailman/listinfo/python-list or, via email, send a message with subject or body 'help' to python-list-requ...@python.org You can reach the person managing the list at python-list-ow...@python.org When replying, please edit your Subject line so it is more specific than Re: Contents of Python-list digest... Today's Topics: 1. Re: Have you read the Python docs lately? (Terry Reedy) 2. Re: Reliably call code after object no longer exists or is unreachable? (Gregory Ewing) 3. argparse parser stores lists instead of strings (Andrew Berg) 4. Re: unpickling derived LogRecord in python 2.7 from python2.6 (Peter Otten) 5. Re: Access violation reading 0x0010 (yuan zheng) 6. Re: argparse parser stores lists instead of strings (Peter Otten) 7. Re: use of index (beginner's question) (Iain King) 8. Re: argparse parser stores lists instead of strings (Gabriel Genellina) 9. Re: Access violation reading 0x0010 (Gabriel Genellina) 10. Spurious character in IOError exception (loial) Ce message ne peut être affiché à cause de son format. Veuillez demander à l’expéditeur de le renvoyer en utilisant un autre format ou un autre logiciel de courrier. multipart/alternative -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Read-write lock for Python
On Thu, Apr 28, 2011 at 4:28 PM, Jean-Michel Pichavant jeanmic...@sequans.com wrote: Geoff Bache wrote: Hi all, I currently find myself needing a Python read-write lock. I note that there is none in the standard library, but googling python read-write lock quickly produced 6 different competing examples, including two languishing patch proposals for the standard library. I can always pick a random one and hope for the best, but I was hoping someone here might have a tip for one that has been used and debugged and is likely to work. Regards, Geoff Bache What about http://docs.python.org/library/threading.html#lock-objects Those aren't read-write locks. They are basic locks, which don't distinguish between readers and writers. I need to be able to lock between reader and writer operations, without readers locking each other out. /Geoff -- http://mail.python.org/mailman/listinfo/python-list
Re: Equivalent code to the bool() built-in function
Albert van der Horst alb...@spenarnc.xs4all.nl wrote: I guess I never thought about it, but there isn't an 'xor' operator to go along with 'or' and 'and'. Must not be something I need very often. There is. applied to booleans is xor. Best to get into the habit of using '!=' otherwise you'll find Python 3.x a bit frustrating. However, that only works if you have exactly two values: both 'and' and 'or' will extend easily to any number of values: True and False and True False False or False or True or False True but using != for 'xor' doesn't extend the same way: False != False != True False You can use 'sum(...)==1' for a larger number of values but do have to be careful that all of them are bools (or 0|1). -- Duncan Booth http://kupuguy.blogspot.com -- http://mail.python.org/mailman/listinfo/python-list
Re: NaN
On Thu, Apr 28, 2011 at 11:01 AM, Chris Rebert c...@rebertia.com wrote: On Thu, Apr 28, 2011 at 9:21 AM, Eric Snow ericsnowcurren...@gmail.com wrote: There's a big discussion going on at python-dev and python-ideas about NaN (not-a-number, from IEEE 754). I haven't really gotten into any scientific computing or numeric programming so I have never knowingly dealt with NaN. However, I have read the discussions and several things are not clear: 1. Why is NaN not an exception? (not why not change it to one? Changing it now would probably break stuff.) Most things that would produce NaN [e.g. x/0, sqrt(-abs(x))] in lower-level languages do produce exceptions in Python. If you encounter a NaN in Python, it was probably either explicitly created or came from a C extension library. It's basically an abstraction leaked through from C/hardware for compatibility. 2. What are the use cases for NaN? Looks like it gets used a lot as a numeric (float?) object with non-value. FWICT, it's useful in lower-level languages (which typically lack exceptions and often lack nice ways of returning multiple values from a function) as a convenient way of signaling a mathematical error. It also lets some calculations continue to limp along (albeit with a NaN result) after an error rather than forcing the probably slower explicit handling of the error at the time of its occurrence. And it's used to represent missing numeric data values, sort of like a numerical None/Null: How much does the truck weigh? NaN (i.e. No idea; we haven't put it on the scale yet). Thanks Chris. That's really helpful. Sounds like NaN is a pretty overloaded object. Nick Coghlan brought up in the issue tracker that it is useful for prototyping algorithms that will be converted to C. Other than that, why should Python care? We have None. Is it for performance (since None acts like a number in some ways, but NaN acts like it better)? Is the problem less with NaN (number object with an undefined value) and more with the broken reflexivity with regards to equality in general (x is x doesn't imply that x == x)? Looks like that situation breaks a number of different operations in Python, whether or not NaN is involved. This stuff is way outside my realm of experience so I don't want to wade into the core lists with these questions, but I want to understand the issues too... -eric Cheers, Chris -- http://rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Python 3.2 Tkinter and TTK
Just downloaded Python3.2 from python's site and attempted to run some of the examples in the 24.2.10Tk Styling. The button worked, but the menu didn't. I also tried a couple from the TKDocs web site. Only errors from there. So, what do I need to do to get it to run? -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
On Thu, Apr 28, 2011 at 11:15 AM, Ethan Furman et...@stoneleaf.us wrote: For anybody interested in composition instead of multiple inheritance, I have posted this recipe on ActiveState (for python 2.6/7, not 3.x): http://code.activestate.com/recipes/577658-composition-of-classes-instead-of-multiple-inherit/ Comments welcome! ~Ethan~ -- http://mail.python.org/mailman/listinfo/python-list That's cool. And if Spam and Eggs were abstract base classes you could register TestAll to them. Granted, that is not so applicable in your example. But generally that would help bridge the inheritance gap for isinstance cases. -eric p.s. I would have commented on the recipe but could not log in... -- http://mail.python.org/mailman/listinfo/python-list
Re: Read-write lock for Python
On Thu, 28 Apr 2011 19:14:45 +0200 Geoff Bache geoff.ba...@gmail.com wrote: On Thu, Apr 28, 2011 at 4:28 PM, Jean-Michel Pichavant jeanmic...@sequans.com wrote: What about http://docs.python.org/library/threading.html#lock-objects Those aren't read-write locks. They are basic locks, which don't distinguish between readers and writers. I need to be able to lock between reader and writer operations, without readers locking each other out. There really isn't any such thing as read-write locks. In fact, the term locks without any further explanation is pretty loose in any case. You can use the above method to implement your own locking scheme. However, that only works if your application is a single, multi-threaded app. Is that the case? When I saw your original question I thought that you needed something inter-process. If so then you need another scheme. I think you have to first clarify your requirements and ask again. I have gleaned a little more information from your above response, you don't require readers to be locked out during an update if I understand the requirement. There is still a lot of information missing. For example: - What is being read and written? Files? - Is this a single multi-threaded app or multiple processes? - if multiple processes, can they be counted on to cooperate? - Do update requests need to be queued or is random availability OK? Now, don't just answer the above questions. Try to start with that and think about what other requirements you have. The more information you give us, the better the answer will be. You may even find that locking is not the actual answer you need. People do have a tendency to offer solutions when they think they are asking questions. Don't pre-suppose the answer. http://www.catb.org/~esr/faqs/smart-questions.html is always a good read in these situations. -- D'Arcy J.M. Cain da...@druid.net | Democracy is three wolves http://www.druid.net/darcy/| and a sheep voting on +1 416 425 1212 (DoD#0082)(eNTP) | what's for dinner. -- http://mail.python.org/mailman/listinfo/python-list
Re: I think I found a mistake in the official language reference documentation -- or I am missing somethig???
On 27 abr, 21:29, MRAB pyt...@mrabarnett.plus.com wrote: On 27/04/2011 21:02, Igor Soares wrote: Reading the section 6.11. The import statement http://docs.python.org/py3k/reference/simple_stmts.html#the-import-st... I found: Import statements are executed in two steps: (1) find a module, and initialize it if necessary; (2) define a name or names in the local namespace (of the scope where the import statement occurs). (...) The first form (without from) repeats these steps for each identifier in the list. The form with from performs step (1) once, and then performs step (2) repeatedly. In the last sentence, isn't it the opposite? With the from form it would find/initialize all the modules and define just the name after from. Or am I missing something? The from form is like: from monty import spam, eggs The steps are: 1. find module monty, and initialize it if necessary 2. define name spam in the local namespace 3. define name eggs in the local namespace Also note that the name monty itself never enters the local namespace. My mistake... I got confused with wrong code in IDLE... I also didn't understand that section ( 6.11 ) at first Thank you guys for the help -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
Ethan Furman wrote: For anybody interested in composition instead of multiple inheritance, I have posted this recipe on ActiveState (for python 2.6/7, not 3.x): http://code.activestate.com/recipes/577658-composition-of-classes-instead-of-multiple-inherit/ Comments welcome! ~Ethan~ Sounds great. But I fear that would completely fool any linter. JM -- http://mail.python.org/mailman/listinfo/python-list
Re: NaN
On Thu, 28 Apr 2011 10:01:49 -0700, Chris Rebert wrote: 2. What are the use cases for NaN? Looks like it gets used a lot as a numeric (float?) object with non-value. [...] And it's used to represent missing numeric data values, sort of like a numerical None/Null: How much does the truck weigh? NaN (i.e. No idea; we haven't put it on the scale yet). While it is common, it is also an abuse of NANs to use it to represent missing values. In Python, that's (probably) best done with None. The statistics language R has a specific value NA to use for missing, distinct from NANs. Still, it could be worse... I've seen a programs use to represent missing values, on the basis that nobody could ever have more than (say) 5000 invoices in the database... (I wish I was exaggerating.) -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE lost from Windows menu !
On Apr 28, 12:28 pm, Uncle Ben b...@greenba.com wrote: I have lost the convenient feature that to edit a .py file I could right-click on the file name and reach the menu item Edit with IDLE. The workaround is not hard, but it wouild be nice to get this feature back. It happened when I was mungeing around and downloaded Python 2.3.3 in addition to Python 2.7.1, and got into trouble until I discovered that I was involuntarily RUNNING the older version. So I cleaned it out, but still I have this aftermath. Is there a Windows guru out there who can tell be how to add to the right-click menu clicking on myfile.py? Uncle Ben It was suggested to me privately that I search for HKEY_CLASSES_ROOT\*\shell, right_click on shell, create a new key called EDIT with IDLE and another called command python.exe %1 Problem: Searching on the HKEY group as above yields no shell. Did I not do it right, or is there another way? (I would think that that command would execute my file, not edit it. But maybe I will be surprised.) (I am running Windows 7, 64-bit.) Uncle Ben -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE lost from Windows menu !
On 28/04/2011 20:11, Uncle Ben wrote: On Apr 28, 12:28 pm, Uncle Benb...@greenba.com wrote: I have lost the convenient feature that to edit a .py file I could right-click on the file name and reach the menu item Edit with IDLE. The workaround is not hard, but it wouild be nice to get this feature back. It happened when I was mungeing around and downloaded Python 2.3.3 in addition to Python 2.7.1, and got into trouble until I discovered that I was involuntarily RUNNING the older version. So I cleaned it out, but still I have this aftermath. Is there a Windows guru out there who can tell be how to add to the right-click menu clicking on myfile.py? Uncle Ben It was suggested to me privately that I search for HKEY_CLASSES_ROOT\*\shell, right_click on shell, create a new key called EDIT with IDLE and another called command python.exe %1 Problem: Searching on the HKEY group as above yields no shell. Did I not do it right, or is there another way? (I would think that that command would execute my file, not edit it. But maybe I will be surprised.) (I am running Windows 7, 64-bit.) Probably the simplest solution would be to install the appropriate version of Python again. -- http://mail.python.org/mailman/listinfo/python-list
Re: socket.gethostbyaddr() wrongly returning a DNS CNAME as the 'primary' hostname
In article
850c85c0-be6e-4eec-b6b1-5c79e1716...@glegroupsg2000goo.googlegroups.com
, cjblaine cjbla...@gmail.com wrote:
Python 2.7.1 (perhaps others)
I believe this is a bug. Comments?
Docs state: Return a triple (hostname, aliaslist, ipaddrlist)
where hostname is the primary host name responding to the
given ip_address, aliaslist is a (possibly empty) list of
alternative host names for the same address, and ipaddrlist
is a list of IPv4/v6 addresses for the same interface on the
same host (most likely containing only a single address).
my-dns-cname.our.org is a CNAME record for primary.our.org
primary.our.org has IP address xx.xx.xx.xx
import socket
socket.gethostbyaddr('xx.xx.xx.xx')
returns:
('my-dns-cname.our.org', ['primary.our.org'], ['xx.xx.xx.xx'])
socket.gethostbyaddr() is pretty much just a transparent wrapper around
the platform's C library function of the same name. See if a simple C
program with a similar call to gethostbyaddr produces the same results.
The code in question for Python 2.7 is here:
http://hg.python.org/cpython/file/a6b772599594/Modules/socketmodule.c
--
Ned Deily,
n...@acm.org
--
http://mail.python.org/mailman/listinfo/python-list
Zope with mySQL
Hi, i am doing web development with Zope. My connected database is mySQL. I am new to this combination.I have to upload the files to mySQL with programming in zope and then downloading them via zope.Can you help me in this regard? I will be very thankfull to you. Regards, Harry -- View this message in context: http://old.nabble.com/Zope-with-mySQL-tp31499628p31499628.html Sent from the Python - python-list mailing list archive at Nabble.com. -- http://mail.python.org/mailman/listinfo/python-list
Where to start in writing test programs for electronics
I would like to write test programs that will collect data over the serial port, control instruments, plot data as its collected, and save that data to a file. I have partially figured out instrument control and have downloaded numpy and matplot. I am having trouble pulling it together as regards feeding realtime data into matplot. I am reading as much as I can in all areas and I'm hoping someone can give me some guidance or tips as to how best to proceed with this. Thanks in advance. -- http://mail.python.org/mailman/listinfo/python-list
Re: Have you read the Python docs lately?
On Apr 28, 12:40 am, Ben Finney ben+pyt...@benfinney.id.au wrote: This one in particular was sorely needed, especially its early if-then discussion of whether to use ‘logging’ at all. For that when to use logging part, you can thank Nick Coghlan :-) Thanks are also due to all those who commented on early drafts, which were put together initially for the 3.2 release. If anyone has any other improvements to suggest, keep 'em coming! Regards, Vinay Sajip -- http://mail.python.org/mailman/listinfo/python-list
Re: socket.gethostbyaddr() wrongly returning a DNS CNAME as the 'primary' hostname
Thanks for the reply, Ned. Bummer for me. Check this out: C code on Solaris 10 SPARC returns the following with nscd running (the Solaris Naming Services Caching Daemon, on by default): PRIMARY according to gethostbyaddr(): my-dns-cname.our.org ALIAS according to gethostbyaddr(): primary.our.org However, I can stop/start nscd and get the complete opposite (correct) result. C code on Solaris 10 SPARC returns the following with nscd OFF: PRIMARY according to gethostbyaddr(): my-dns-cname.our.org ALIAS according to gethostbyaddr(): primary.our.org These then ALTERNATE consistently with every successive invocation of my code. C code on Linux 2.6 with glibc 2.5 returns: PRIMARY according to gethostbyaddr(): primary.our.org [ no aliases get listed ] Time to query the corporate DNS folks. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 3.2 Tkinter and TTK
Man, If you want to programm GUI's it is better for you learn Qt or GTK. They are so much better than tkinter. I told this with sadness because I like free things, but the reality is not like this. This libs are in all places. --- Jayme Proni Filho Skype: jaymeproni Twitter: @jaymeproni Phone: +55 - 17 - 3631 - 6576 Mobile: +55 - 17 - 9605 - 3560 e-Mail: jaymeproni at yahoo dot com dot br --- -- http://mail.python.org/mailman/listinfo/python-list
Re: Deditor
On 28 apr, 07:46, jmfauth wxjmfa...@gmail.com wrote: On 27 avr, 19:22, Alec Taylor alec.tayl...@gmail.com wrote: Thanks, any plans for a Windows version? - Download the deb - Unpack it with a utility like 7zip - Throw away the unnecessary stuff, (keep the deditor part) - Depending on your libs, adatpt the import - Launch deditor.py - Then ... [5 minutes] In fact, this kind of app can be simply packed in a zip file. jmf It isn't that easy as you might have hoped ;) I'm using wxpython for rendering the GUI somehow some things that work in the linux version break in the windows version so I need to do some small modifications and as I'm a hardcore linux fan I ony use windows for gaming it usually takes a little longer for a windows release, I'm releasing a tarball now btw :D -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE lost from Windows menu !
On Apr 28, 3:29 pm, MRAB pyt...@mrabarnett.plus.com wrote: On 28/04/2011 20:11, Uncle Ben wrote: On Apr 28, 12:28 pm, Uncle Benb...@greenba.com wrote: I have lost the convenient feature that to edit a .py file I could right-click on the file name and reach the menu item Edit with IDLE. The workaround is not hard, but it wouild be nice to get this feature back. It happened when I was mungeing around and downloaded Python 2.3.3 in addition to Python 2.7.1, and got into trouble until I discovered that I was involuntarily RUNNING the older version. So I cleaned it out, but still I have this aftermath. Is there a Windows guru out there who can tell be how to add to the right-click menu clicking on myfile.py? Uncle Ben It was suggested to me privately that I search for HKEY_CLASSES_ROOT\*\shell, right_click on shell, create a new key called EDIT with IDLE and another called command python.exe %1 Problem: Searching on the HKEY group as above yields no shell. Did I not do it right, or is there another way? (I would think that that command would execute my file, not edit it. But maybe I will be surprised.) (I am running Windows 7, 64-bit.) Probably the simplest solution would be to install the appropriate version of Python again.- Hide quoted text - - Show quoted text - Tried that. No change. Strange things are happening! -- http://mail.python.org/mailman/listinfo/python-list
Re: Read-write lock for Python
On Thu, Apr 28, 2011 at 7:53 PM, D'Arcy J.M. Cain da...@druid.net wrote: On Thu, 28 Apr 2011 19:14:45 +0200 Geoff Bache geoff.ba...@gmail.com wrote: On Thu, Apr 28, 2011 at 4:28 PM, Jean-Michel Pichavant jeanmic...@sequans.com wrote: What about http://docs.python.org/library/threading.html#lock-objects Those aren't read-write locks. They are basic locks, which don't distinguish between readers and writers. I need to be able to lock between reader and writer operations, without readers locking each other out. There really isn't any such thing as read-write locks. Did you google it? I even provided the exact search terms to use in my initial posting. It takes you straight to two standard library patch proposals and four other solutions, all labelled this way (sometimes reader-writer locks admittedly). That doesn't happen if it isn't a standard problem. I'm not looking for general advice on how to solve some specific problem. I'm asking if anyone knows anything about the relative merits of the above 6 solutions. Regards, Geoff Bache -- http://mail.python.org/mailman/listinfo/python-list
Re: NaN
On 2011-04-28, Chris Rebert c...@rebertia.com wrote: 2. What are the use cases for NaN? Looks like it gets used a lot as a numeric (float?) object with non-value. FWICT, it's useful in lower-level languages (which typically lack exceptions and often lack nice ways of returning multiple values from a function) as a convenient way of signaling a mathematical error. When doing stuff involving process control systems, I found it very useful to use NaN to indicate unknown/invalid. It propogates properly through calculations so that when you have an invalid input, all of the outputs that depend on it also go invalid. The other option is to use a value/status tuple everywhere you would normally use a float. But that falls over every time you need to use a library function that expects a float as an input and returns a float as an output. Since the sensors return a NaN when the value is unkown/invalid it seemed logical to continue with that paradigm in my Python code -- and it pretty much just works. -- Grant Edwards grant.b.edwardsYow! If elected, Zippy at pledges to each and every gmail.comAmerican a 55-year-old houseboy ... -- http://mail.python.org/mailman/listinfo/python-list
Re: [OT] VCS tools (was Development tools and practices for Pythonistas)
This has been a pretty informative thread so far. Please keep it coming. I am a hardware development guy and do very little software development. I have been vaguely aware of tools for version control but inspired by this thread I have started looking at Mercurial. My humble contribution (from my boss really) since I have not seen it mentioned here: http://code.google.com/p/gource/ (I have zero experience of gource so there is no point in asking me questions) /Martin -- http://mail.python.org/mailman/listinfo/python-list
Re: use of index (beginner's question)
On Thu, 28 Apr 2011 01:49:33 +0100, Chris Angelico ros...@gmail.com
wrote:
On Thu, Apr 28, 2011 at 10:42 AM, Rusty Scalf iai-...@sonic.net wrote:
list1 = ['pig', 'horse', 'moose']
list2 = ['62327', '49123', '79115']
n = 2
s2 = list + `n`
a = s2[list1.index('horse')]
print a
s2 is a string with the value list2; this is not the same as the
variable list2. You could use eval to convert it, but you'd do better
to have a list of lists:
lists = [
['pig', 'horse', 'moose']
['62327', '49123', '79115']
]
Then you could use:
n = 2
a = lists[n][list1.index('horse')]
*cough* I think you mean
n = 1
a = lists[n][list[0].index('horse')]
The alternative would be to have a dictionary of lists:
lists = {
list1: ['pig', 'horse', 'moose'],
list2: ['62327', '49123', '79115']
}
n = 2
s2 = list + str(n)
a = lists[s2][lists[list1].index('horse')]
Both of these can be made less ugly if the list you want to index into
isn't one of the lists you might want to look up, but that's just a detail.
--
Rhodri James *-* Wildebeest Herder to the Masses
--
http://mail.python.org/mailman/listinfo/python-list
subclassing an extension (non built-in) class / type in python 3.2
Hello everybody, I read in the extending and embedding documentation of python 3, that it is easily possible to subclass or subtype a built-in type. However, in my case, I would like to subclass a class, defined in a external python-file (py), which I can import in my C++-application and access the class by the module's dictionary. Does anybody have an example or just a hint, how to successfully realize this type of inheritance? I will be grateful for every response. Cheers Marc -- GMX DSL Doppel-Flat ab 19,99 Euro/mtl.! Jetzt mit gratis Handy-Flat! http://portal.gmx.net/de/go/dsl -- http://mail.python.org/mailman/listinfo/python-list
Fwd: subclassing an extension (non built-in) class / type in python 3.2
Hello everybody, I read in the extending and embedding documentation of python 3, that it is easily possible to subclass or subtype a built-in type. However, in my case, I would like to subclass a class, defined in a external python-file (py), which I can import in my C++-application and access the class by the module's dictionary. Does anybody have an example or just a hint, how to successfully realize this type of inheritance? I will be grateful for every response. Cheers Marc -- NEU: FreePhone - kostenlos mobil telefonieren und surfen! Jetzt informieren: http://www.gmx.net/de/go/freephone -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE lost from Windows menu !
On 2011.04.28 02:11 PM, Uncle Ben wrote: It was suggested to me privately that I search for HKEY_CLASSES_ROOT\*\shell, right_click on shell, create a new key called EDIT with IDLE and another called command python.exe %1 The key you're looking for is HKCR\Python.File\shell. Add a subkey called Edit with IDLE. Create a subkey in there called command. Inside HKCR\Python.File\shell\Edit with IDLE\command, modify the default value to C:\Python32\pythonw.exe C:\Python32\Lib\idlelib\idle.pyw -e %1 (changing the paths if necessary). Do the same with HKCR\Python.NoConFile\shell to get the command for .pyw files. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 3.2 Tkinter and TTK
If you want to programm GUI's it is better for you learn Qt or GTK. They are so much better than tkinter. I told this with sadness because I like free things, but the reality is not like this. This libs are in all places. --- Jayme Proni Filho My experience with tkinter and Python 3.2 is more positive. I wrote a GUI for an editing program (editing like publishers think of it, not programmers) that was fairly complex with three different list boxes, an information pane, a toolbar, and a pane for the text being edited (implemented with a Text widget). Admittedly it took a little trial and error to perfect the layout of the various frames, but when it was done, I was pleased with the appearance, functionality, and performance. David Phillips -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE lost from Windows menu !
On 4/28/2011 12:28 PM, Uncle Ben wrote: I have lost the convenient feature that to edit a .py file I could right-click on the file name and reach the menu item Edit with IDLE. The workaround is not hard, but it wouild be nice to get this feature back. It happened when I was mungeing around and downloaded Python 2.3.3 in addition to Python 2.71, and got into trojuble uintil I discovered that I was involuntarily RUNNING the older version. So I cleaned it out, but still I have this aftermath. Is there a Windows guru out there who can tell be how to add to the right-click menu clicking on myfile.py? In Window98, one could get from Explorer Window to a file-associations dialog/window/tool that would let you change/add 'open', 'open with x', 'run', for a particular file type without using the registry editor, which is slightly dangerous. I have forgotten how to find it in xp, and no idea in w7. I would look in windows help and or control panel. -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: NaN
On 4/28/2011 2:59 PM, Steven D'Aprano wrote: Still, it could be worse... I've seen a programs use to represent missing values, on the basis that nobody could ever have more than (say) 5000 invoices in the database... (I wish I was exaggerating.) All 9s in a field for missing was once standard for Fortran programs. -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: Read-write lock for Python
Geoff Bache geoff.ba...@gmail.com writes: I currently find myself needing a Python read-write lock. Please tell us what you mean by “read-write lock”. I note that there is none in the standard library, but googling python read-write lock quickly produced 6 different competing examples, including two languishing patch proposals for the standard library. That's probably because the term isn't well defined. What is your definition? -- \ “If you can't beat them, arrange to have them beaten.” —George | `\Carlin | _o__) | Ben Finney -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
Ethan Furman et...@stoneleaf.us writes: For anybody interested in composition instead of multiple inheritance, I have posted this recipe on ActiveState (for python 2.6/7, not 3.x): http://code.activestate.com/recipes/577658-composition-of-classes-instead-of-multiple-inherit/ Comments welcome! It doesn't look like composition at all, though. I understand composition to be the setting of attributes on a class or instance; that recipe doesn't show it very well IMO. -- \ “[The RIAA] have the patience to keep stomping. They're playing | `\ whack-a-mole with an infinite supply of tokens.” —kennon, | _o__) http://kuro5hin.org/ | Ben Finney -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 3.2 Tkinter and TTK
On 4/28/2011 1:33 PM, steven.oldner wrote: Just downloaded Python3.2 from python's site and attempted to run some of the examples in the 24.2.10 Tk Styling. The button worked, I found 4 examples, none of which *do* anything. Perhaps they are only meant to show syntax. I am running WinXP. You? .Style: .configure OK .map OK .layout OK? Text says it is not intended to do anything useful and indeed the displayed button does nothing when pressed. .theme_settings OK? I do not see any green or olive but the menu didn't. What do *you* mean by 'did not work'? They all compile and display something, but I would have to study more before I would know what to expect. It is possible that the examples have bugs, or that the ttk module does. Either should be reported on the tracker. Others have used it though. I also tried a couple from the TKDocs web site. Only errors from there. Syntax error? Runtime exception? or just not look/act as you expect? -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: [OT] VCS tools
Martin Schöön martin.sch...@gmail.com writes: This has been a pretty informative thread so far. Please keep it coming. I am a hardware development guy and do very little software development. I have been vaguely aware of tools for version control but inspired by this thread I have started looking at Mercurial. After my passionate Bazaar evangelism? :-) I seriously recommend anyone looking for a modern VCS to give Bazaar a decent trial. It's the one I've found newcomers learn most easily, and it's astoundingly flexible as one's needs with it grow. -- \ “I'm a born-again atheist.” —Gore Vidal | `\ | _o__) | Ben Finney -- http://mail.python.org/mailman/listinfo/python-list
Re: NaN
On 2011-04-28, Steven D'Aprano steve+comp.lang.pyt...@pearwood.info wrote: While it is common, it is also an abuse of NANs to use it to represent missing values. In Python, that's (probably) best done with None. None won't propogate through calculations to produce None's on outputs. The statistics language R has a specific value NA to use for missing, distinct from NANs. Still, it could be worse... I've seen a programs use to represent missing values, on the basis that nobody could ever have more than (say) 5000 invoices in the database... All 1's in a float is a NaN, so all 9's in a BCD value is a NaN. Sort of makes sense if the BCD operations propogate all-nine values or raise exceptions when they are encountered (that's a big if). -- Grant Edwards grant.b.edwardsYow! If elected, Zippy at pledges to each and every gmail.comAmerican a 55-year-old houseboy ... -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
On Thursday, April 28, 2011 10:15:02 AM UTC-7, Ethan Furman wrote: For anybody interested in composition instead of multiple inheritance, I have posted this recipe on ActiveState (for python 2.6/7, not 3.x): http://code.activestate.com/recipes/577658-composition-of-classes-instead-of-multiple-inherit/ Comments welcome! That's not what we mean by composition. Composition is when one object calls upon another object that it owns to implement some of its behavior. Often used to model a part/whole relationship, hence the name. The sorts of class that this decorator will work for are probably not the ones that are going to have problems cooperating in the first place. So you might as well just use inheritance; that way people trying to read the code will have a common, well-known Python construct rather than a custom decorator to understand. If you want to enforce no duplication of attributes you can do that, such as with this untested metaclass: class MakeSureNoBasesHaveTheSameClassAttributesMetaclass(type): def __new__(metatype,name,bases,dct): u = collections.Counter() for base in bases: for key in base.__dict__.keys(): u[key] += 1 for key in dct.keys(): u[key] += 1 if any(u[key] 1 for key in u.keys()): raise TypeError(base classes and this class share some class attributes) return type.__new__(metatype,name,bases,dct) Carl Banks -- http://mail.python.org/mailman/listinfo/python-list
Re: Read-write lock for Python
On Thu, 2011-04-28 at 07:02 -0700, Geoff Bache wrote: Hi all, I currently find myself needing a Python read-write lock. I note that there is none in the standard library, but googling python read-write lock quickly produced 6 different competing examples, including two languishing patch proposals for the standard library. I can always pick a random one and hope for the best, but I was hoping someone here might have a tip for one that has been used and debugged and is likely to work. I wrote and have used the SHLock class in threading2 which should do what you need. Don't know about likely to work but if it doesn't, I'd like to hear about it so I can fix it :-) `pip install threading2` Cheers, Ryan -- Ryan Kelly http://www.rfk.id.au | This message is digitally signed. Please visit r...@rfk.id.au| http://www.rfk.id.au/ramblings/gpg/ for details signature.asc Description: This is a digitally signed message part -- http://mail.python.org/mailman/listinfo/python-list
Re: [OT] VCS tools
On 04/28/2011 04:50 PM, Ben Finney wrote: This has been a pretty informative thread so far. Please keep it coming. I am a hardware development guy and do very little software development. I have been vaguely aware of tools for version control but inspired by this thread I have started looking at Mercurial. After my passionate Bazaar evangelism? :-) I must say my takeaway from the thread was (1) check back in on Bazaar to see if the speed is better than I remember and (2) Fossil, wha? wow! -tkc -- http://mail.python.org/mailman/listinfo/python-list
Re: [OT] VCS tools
On Fri, Apr 29, 2011 at 8:50 AM, Ben Finney ben+pyt...@benfinney.id.au wrote: Martin Schöön martin.sch...@gmail.com writes: I seriously recommend anyone looking for a modern VCS to give Bazaar a decent trial. It's the one I've found newcomers learn most easily, and it's astoundingly flexible as one's needs with it grow. When I was deciding what DVCS I should use for personal projects, Bzr was first thing I tried. It was quite uncomfortable experience after svn, esp. with branches and merges, working not the way I was expecting it to. Mercurial, on the contrary, did exactly what I was expecting it to, and was overall very easy to learn. -- With best regards, Daniel Kluev -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE lost from Windows menu !
On Apr 28, 3:11 pm, Uncle Ben b...@greenba.com wrote: On Apr 28, 12:28 pm, Uncle Ben b...@greenba.com wrote: I have lost the convenient feature that to edit a .py file I could right-click on the file name and reach the menu item Edit with IDLE. The workaround is not hard, but it wouild be nice to get this feature back. It happened when I was mungeing around and downloaded Python 2.3.3 in addition to Python 2.7.1, and got into trouble until I discovered that I was involuntarily RUNNING the older version. So I cleaned it out, but still I have this aftermath. Is there a Windows guru out there who can tell be how to add to the right-click menu clicking on myfile.py? Uncle Ben It was suggested to me privately that I search for HKEY_CLASSES_ROOT\*\shell, right_click on shell, create a new key called EDIT with IDLE and another called command python.exe %1 Problem: Searching on the HKEY group as above yields no shell. Did I not do it right, or is there another way? (I would think that that command would execute my file, not edit it. But maybe I will be surprised.) (I am running Windows 7, 64-bit.) Uncle Ben Thanks to all for good help. I finally got what I need by altering the original advice (A.W.) slightly. The key to edit was HKCR/Applications/python.exe/shell, the item is put into the menu in a sub-key labelled Edit with IDLE, and the command sub-sub-key that works for me is idle.bat %1 I will keep Andrew Berg's note and use it when I encounter .pyw files. Python's the ninth language I've had to learn. And I love it. Uncle Ben -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE lost from Windows menu !
On Apr 28, 5:17 pm, Andrew Berg bahamutzero8...@gmail.com wrote: On 2011.04.28 02:11 PM, Uncle Ben wrote: It was suggested to me privately that I search for HKEY_CLASSES_ROOT\*\shell, right_click on shell, create a new key called EDIT with IDLE and another called command python.exe %1 The key you're looking for is HKCR\Python.File\shell. Add a subkey called Edit with IDLE. Create a subkey in there called command. Inside HKCR\Python.File\shell\Edit with IDLE\command, modify the default value to C:\Python32\pythonw.exe C:\Python32\Lib\idlelib\idle.pyw -e %1 (changing the paths if necessary). Do the same with HKCR\Python.NoConFile\shell to get the command for .pyw files. Thanks to all for good help. I finally got what I need by altering the original advice (A.T.) slightly. The key to edit was HKCR/Applications/python.exe/shell, the item is put into the menu in a sub-key labelled Edit with IDLE, and the command sub-sub-key that works for me is idle.bat %1 I will keep Andrew Berg's note and use it when I encounter .pyw files. Python's the ninth language I've had to learn. And I love it. Uncle Ben -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
Carl Banks wrote: That's not what we mean by composition. Composition is when one object calls upon another object that it owns to implement some of its behavior. Often used to model a part/whole relationship, hence the name. Hmmm. Okay -- any ideas for a better term? Something that describes taking different source classes and fusing them into a new whole, possibly using single-inheritance... Frankenstein, maybe? ;) The sorts of class that this decorator will work for are probably not the ones that are going to have problems cooperating in the first place. So you might as well just use inheritance; that way people trying to read the code will have a common, well-known Python construct rather than a custom decorator to understand. From thread 'python and super' on Python-Dev: Ricardo Kirkner wrote: I'll give you the example I came upon: I have a TestCase class, which inherits from both Django's TestCase and from some custom TestCases that act as mixin classes. So I have something like class MyTestCase(TestCase, Mixin1, Mixin2): ... now django's TestCase class inherits from unittest2.TestCase, which we found was not calling super. This is the type of situation the decorator was written for (although it's too simplistic to handle that exact case, as Ricardo goes on to say he has a setUp in each mixin that needs to be called -- it works fine though if you are not adding duplicate names). ~Ethan~ -- http://mail.python.org/mailman/listinfo/python-list
Re: socket.gethostbyaddr() wrongly returning a DNS CNAME as the 'primary' hostname
On Thu, Apr 28, 2011 at 1:18 PM, cjblaine cjbla...@gmail.com wrote: Thanks for the reply, Ned. Bummer for me. Check this out: C code on Solaris 10 SPARC returns the following with nscd running (the Solaris Naming Services Caching Daemon, on by default): I'm guessing the IP's PTR record is pointing to a CNAME rather than (one of) the A record(s). -- http://mail.python.org/mailman/listinfo/python-list
回复: Re: Need your help
Dear Thomas,JM,Chris Rebert:
I got it. Thank you very very very much.
Best Regards
2011-04-29
1011_wxy
发件人: Thomas Rachel
nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa...@spamschutz.glglgl.de
发送时间: 2011-04-28 21:26
主 题: Re: Need your help
收件人: python-list@python.org
Am 28.04.2011 13:14, schrieb Chris Rebert:
import a, b, sys
def c():
orig_stdout = sys.stdout
sys.stdout = open('my_log_file.log', 'w')
a.a()
b.b()
sys.stdout.close()
sys.stdout = orig_stdout
Someone may have written a with-statement context manager that
abstracts away the swapping.
@contextlib.contextmanager
def swap_stdout(target):
orig_stdout = sys.stdout
sys.stdout = target
try:
yield target
finally:
sys.stdout = orig_stdout
In this case, I can use all kinds of files (open() files, StringIO
objects etc.), and can re-use them if necessary, in order to
prepend/append data.
Closing can happen additionally, if the user wants.
Thomas
--
http://mail.python.org/mailman/listinfo/python-list --
http://mail.python.org/mailman/listinfo/python-list
Aborting Python from C code
In our sandboxed Python environment, I would like to be able to trigger an abort of the currently-running Python script (from a signal handler or another thread). Currently, I use PyErr_SetInterrupt() which raises KeyboardInterrupt in the script; this works for the most part, but can be bypassed with a script like: while True: try: while True: pass except: pass I want to be able to administratively order Python to stop executing. Is it possible to make KeyboardInterrupt non-catchable from Python? Alternatively, can I use Py_AddPendingCall to do this? I'd rather not use setjmp/longjmp if I can help it, as they seem a tad brutal, but I'm thinking in terms of a call that, in effect, doesn't return. Any ideas would be appreciated! Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
On 29/04/2011 02:43, Ethan Furman wrote: Carl Banks wrote: That's not what we mean by composition. Composition is when one object calls upon another object that it owns to implement some of its behavior. Often used to model a part/whole relationship, hence the name. Hmmm. Okay -- any ideas for a better term? Something that describes taking different source classes and fusing them into a new whole, possibly using single-inheritance... Frankenstein, maybe? ;) [snip] Fusing/fusion? Compounding? -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE lost from Windows menu !
Search for the following key in regedit: HKEY_CLASSES_ROOT\*\shell Right click on “shell”, choose create new key. Name it “Edit with IDLE Create a new key below that one and call it “command.” Now double click on the (Default) value that you will find in the right hand pane, and type in the following: python.exe %1 (or if you don't have it in your PATH, then put in the absolute python directory, ie: C:\Python27\bin\python.exe) -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE lost from Windows menu !
I agree with MRAB because it is easy and fast solution. --- Jayme Proni Filho Skype: jaymeproni Twitter: @jaymeproni Phone: +55 - 17 - 3631 - 6576 Mobile: +55 - 17 - 9605 - 3560 e-Mail: jaymeproni at yahoo dot com dot br --- -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
On Thu, 28 Apr 2011 15:35:47 -0700, Carl Banks wrote: On Thursday, April 28, 2011 10:15:02 AM UTC-7, Ethan Furman wrote: For anybody interested in composition instead of multiple inheritance, I have posted this recipe on ActiveState (for python 2.6/7, not 3.x): http://code.activestate.com/recipes/577658-composition-of-classes- instead-of-multiple-inherit/ Comments welcome! That's not what we mean by composition. Composition is when one object calls upon another object that it owns to implement some of its behavior. I thought that was delegation. As in, when one object delegates some or all of it's behaviour to another object: http://code.activestate.com/recipes/52295 Often used to model a part/whole relationship, hence the name. In mathematics, composition means to make a function by applying a function to the output of another. E.g.: f o g(x) is equivalent to f(g(x)) (Strictly speaking, the o in the f o g should be a little circle rather than lowercase O.) -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
On Fri, Apr 29, 2011 at 11:43 AM, Ethan Furman et...@stoneleaf.us wrote: Hmmm. Okay -- any ideas for a better term? Something that describes taking different source classes and fusing them into a new whole, possibly using single-inheritance... Frankenstein, maybe? ;) I'd have to say that this is typical of MixIns cheers James -- -- James Mills -- -- Problems are solved by method -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
Ethan Furman et...@stoneleaf.us writes: Carl Banks wrote: That's not what we mean by composition. Composition is when one object calls upon another object that it owns to implement some of its behavior. Often used to model a part/whole relationship, hence the name. Hmmm. Okay -- any ideas for a better term? Something that describes taking different source classes and fusing them into a new whole, possibly using single-inheritance... Frankenstein, maybe? ;) (Remember that Frankenstein was not the monster, but the scientist.) “Hybrid”? -- \ “If sharing a thing in no way diminishes it, it is not rightly | `\ owned if it is not shared.” —Augustine of Hippo (354–430 CE) | _o__) | Ben Finney -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
Steven D'Aprano steve+comp.lang.pyt...@pearwood.info writes: On Thu, 28 Apr 2011 15:35:47 -0700, Carl Banks wrote: That's not what we mean by composition. Composition is when one object calls upon another object that it owns to implement some of its behavior. I thought that was delegation. As in, when one object delegates some or all of it's behaviour to another object: http://code.activestate.com/recipes/52295 The difference being that, with delegation, the object being called is unrelated to this one. With composition, the object being called is not wholly separate, but is instead an attribute on the current object. The “another object that it owns” was, I presume, meant to communicate this “an object which is an attribute of the current one” relationship. In mathematics, composition means to make a function by applying a function to the output of another. The term “composition” in the programming sense comes from OO design, not functional nor mathematical terminology. -- \ “I don't like country music, but I don't mean to denigrate | `\ those who do. And for the people who like country music, | _o__)denigrate means ‘put down’.” —Bob Newhart | Ben Finney -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
On Thu, Apr 28, 2011 at 3:35 PM, Carl Banks pavlovevide...@gmail.com wrote: On Thursday, April 28, 2011 10:15:02 AM UTC-7, Ethan Furman wrote: For anybody interested in composition instead of multiple inheritance, I have posted this recipe on ActiveState (for python 2.6/7, not 3.x): http://code.activestate.com/recipes/577658-composition-of-classes-instead-of-multiple-inherit/ Comments welcome! That's not what we mean by composition. Composition is when one object calls upon another object that it owns to implement some of its behavior. Often used to model a part/whole relationship, hence the name. It's a pretty old idea, that seems to be getting revived in a big way all of a sudden. Perhaps the Java people just rediscovered it? In a Software Engineering class using Ada, the teacher called it Structural Inclusion, and of course it was an important concept in Ada, because Ada had no inheritance. This was in 1989-1990. -- http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
Dan Stromberg drsali...@gmail.com writes: On Thu, Apr 28, 2011 at 3:35 PM, Carl Banks pavlovevide...@gmail.com wrote: That's not what we mean by composition. Composition is when one object calls upon another object that it owns to implement some of its behavior. Often used to model a part/whole relationship, hence the name. It's a pretty old idea, that seems to be getting revived in a big way all of a sudden. Perhaps the Java people just rediscovered it? I think it's more that people keep re-discovering how irredeemably messy multiple inheritance is, and finding that object composition is better in most cases :-) -- \ “There's a fine line between fishing and standing on the shore | `\looking like an idiot.” —Steven Wright | _o__) | Ben Finney -- http://mail.python.org/mailman/listinfo/python-list
Re: use of index (beginner's question)
On Thu, Apr 28, 2011 at 11:42 AM, Rusty Scalf iai-...@sonic.net wrote:
list1 = ['pig', 'horse', 'moose']
list2 = ['62327', '49123', '79115']
n = 2
s2 = list + `n`
a = s2[list1.index('horse')]
print a
-does not work
While advices above are indeed right way to go in your case, there is
a way to get variable by its name.
list2 = ['62327', '49123', '79115']
n = 2
s2 = list{0}.format(n)
print s2
list2
print locals()[s2]
['62327', '49123', '79115']
print locals()[s2][0]
62327
But generally if you need to do that, you would be better with
re-design of your data/architecture.
--
With best regards,
Daniel Kluev
--
http://mail.python.org/mailman/listinfo/python-list
Re: Composition instead of inheritance
On Thu, Apr 28, 2011 at 11:15 AM, Ethan Furman et...@stoneleaf.us wrote: For anybody interested in composition instead of multiple inheritance, I have posted this recipe on ActiveState (for python 2.6/7, not 3.x): http://code.activestate.com/recipes/577658-composition-of-classes-instead-of-multiple-inherit/ Comments welcome! On line 14, is it intentional that attributes whose values happen to be false are not considered as conflicts? On line 31, this code: thing = getattr(thing, '__func__', None) or thing could be simplified to this: thing = getattr(thing, '__func__', thing) Cheers, Ian -- http://mail.python.org/mailman/listinfo/python-list
Python RPM Package build error
Hello List, I am attempting to build an rpm from Python-3.1.3.tar.bz2 with the included spec file from /Python-3.1.3/Misc/RPM/ and it fails with the following error: Does anyone have any ideas? # rpmbuild -ba python-3.1.spec mv: cannot stat `idle': No such file or directory + echo '#!/usr/bin/env python2.6' + echo 'import os, sys' + echo 'os.execvp(/usr/bin/python2.6, [/usr/bin/python2.6, /usr/lib/python3.1/idlelib/idle.py] + sys.argv[1:])' + echo 'print Failed to exec Idle' + echo 'sys.exit(1)' + chmod 755 /var/tmp/python2.6-3.1.3-root/usr/bin/idle2.6 + cp -a Tools /var/tmp/python2.6-3.1.3-root/usr/lib64/python3.1 + rm -f mainpkg.files + find /var/tmp/python2.6-3.1.3-root/usr/lib64/python3.1/lib-dynload -type f + sed 's|^/var/tmp/python2.6-3.1.3-root|/|' + grep -v -e '_tkinter.so$' error: Bad exit status from /var/tmp/rpm-tmp.7647 (%install) /var/tmp/rpm-tmp.7647 include the following: # check to see if there are any straggling #! lines find $RPM_BUILD_ROOT -type f | xargs egrep -n '^#! */usr/local/bin/python' \ | grep ':1:#!' /tmp/python-rpm-files.$$ || true if [ -s /tmp/python-rpm-files.$$ ] then echo '*' cat /tmp/python-rpm-files.$$ cat @EOF * There are still files referencing /usr/local/bin/python in the install directory. They are listed above. Please fix the .spec file and try again. If you are an end-user, you probably want to report this to jafo-r...@tummy.com as well. * @EOF rm -f /tmp/python-rpm-files.$$ exit 1 fi rm -f /tmp/python-rpm-files.$$ # CLEAN /usr/lib/rpm/brp-compress /usr/lib/rpm/brp-strip /usr/lib/rpm/brp-strip-static-archive /usr/lib/rpm/brp-strip-comment-note -- http://mail.python.org/mailman/listinfo/python-list
