Elisa Media Center 0.5.37 Release
Dear Python users, The Elisa team is happy to announce the release of Elisa Media Center 0.5.37, code-named Doubledecker. Elisa is a cross-platform and open-source Media Center written in Python. It uses GStreamer [1] for media playback and pigment [2] to create an appealing and intuitive user interface. This release is a lightweight release, meaning it is pushed through our automatic plugin update system. Additionally a windows installer is available for download on our website. As usual, for users running a version of Elisa = 0.5.35, the upgrade to 0.5.37 should be done automatically via the plugin repository. As usual, tarballs are provided for distribution packagers. A complete list of the issues fixed can be found at: http://bugs.launchpad.net/elisa/+milestone/0.5.37 This is also summarised in the (attached) release notes. Installers and sources can be downloaded from http://elisa.fluendo.com/download/ Bug reports and feature requests are welcome at http://bugs.launchpad.net/elisa/+filebug Have a media-centered evening, Olivier, for the Elisa team [1] http://www.gstreamer.net/ [2] https://code.fluendo.com/pigment/trac Elisa 0.5.37 Doubledecker === This is Elisa 0.5.37, thirty-seventh release of the 0.5 branch. Bugs fixed since 0.5.36: - 357097: Music scan partially fails on Ubuntu Jaunty - 361558: amp master doesn't KILL dead slaves - 330431: Previously played Audio track/video name appears on audio/video plugin - 366152: [win32] Integrate a browser control in the installer - 347174: Local videos thumbnail shown on Internet-video plugins Download You can find source releases of Elisa on the download page: http://elisa.fluendo.com/download Elisa Homepage More details can be found on the project's website: http://elisa.fluendo.com Support and Bugs We use Launchpad for bug reports and feature requests: https://bugs.launchpad.net/elisa/+filebug Developers All code is in a Bazaar branch and can be checked out from there. It is hosted on Launchpad: https://code.launchpad.net/elisa Contributors to this release: - Anna Wojdel - David McLeod - Florian Boucault - Guillaume Emont - Jesús Corrius - Julien Moutte - Krzysztof Adamski - Lionel Martin - Loïc Molinari - Marc Garcia - Maxwell Young - Olivier Tilloy - Philippe Normand -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
CodeInvestigator version 0.11.1
CodeInvestigator version 0.11.1 was released on April 28. Bug fix: - A windows installation issue was resolved. CodeInvestigator is a tracing tool for Python programs. Running a program through CodeInvestigator creates a recording. Program flow, function calls, variable values and conditions are all stored for every line the program executes. The recording is then viewed with an interface consisting of the code. The code can be clicked: A clicked variable displays its value, a clicked loop displays its iterations. You read code, and have at your disposal all the run time details of that code. A computerized desk check tool and another way to learn about your program. http://sourceforge.net/project/showfiles.php?group_id=183942 -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
[ANN] pyOpenSSL 0.9
I'm happy to announce the release of pyOpenSSL 0.9. This release includes several new features and a very important bug fix: * APIs have been introduced to get and set the version of an X509 request * Contexts now support loading CA certificates for verification from a specified directory or from the platform's default certificate store * DTLS-related constants, OP_NO_QUERY_MTU, OP_COOKIE_EXCHANGE, and OP_NO_TICKET are now exposed * X509Extension now has the `get_short_name´ method for retrieving the short form of the extension type * It is now possible to create extensions which use any of the three possible OpenSSL implementation approaches * FILETYPE_TEXT can be used to dump keys, certificate, and CSRs in text format * Various compiler warnings have been fixed * A bug triggered by almost all uses of pyOpenSSL from multiple threads and leading to a crash has been fixed Many thanks to numerous people who contributed patches to this release. You can find pyOpenSSL 0.9 in the downloads area of the SourceForge project page: https://sourceforge.net/project/showfiles.php?group_id=31249 Please use Launchpad to file any bug reports: https://bugs.launchpad.net/pyopenssl Jean-Paul Calderone -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
Re: suggestion on a complicated inter-process communication
On Apr 27, 8:59 pm, Way csw...@gmail.com wrote: Hello friends, I have a little messy situation on IPC. Please if you can, give me some suggestion on how to implement. Thanks a lot! - denotes create MainProcess - Process1 - Process3 (from os.system) | - Process2 (from os.system) - Process4 (from os.system) -Process5 I would like to make the communication between Process1 and Process5. Process1 needs Process5's output to provide argument to generate Process3, and in turn Process5 needs to wait Process3 finished. Thank you very much if you can give a hint. Abstraction should resolve this. What I mean is that Process2 shouldn't be defined in terms of what it actually does, but what it appears to do. If you look at each process and think only what its child processes do and what its parent process expects it to do, then your job should get a lot simpler. Process1 expects Process2 to deliver a set of parameters to spawn Process3, and then it will wait until Process3 terminates. Looking at it this way, questions come to mind: Why can't Process2 run Process3 itself? It's unusual to have one process tell another process what to do when it can simply do it itself. By the way, I've never seen a time when this kind of design is necessary. There are other ways around your problem than spawning a bunch of processes. Each process should really be independent of all the other processes, doing only a very well-specified task in a well- specified way. The only time I could think of doing something like this is when you're getting a webserver setup and Process5 needs to communicate with Process3 to render the page or something like that. But even in that case, each process is really independently defined and implemented. -- http://mail.python.org/mailman/listinfo/python-list
Re: mailbox.mbox.add() sets access time as well as modification time
In message pan.2009.04.28.04.29...@remove.this.cybersource.com.au, Steven D'Aprano wrote: On Tue, 28 Apr 2009 11:19:51 +1200, Lawrence D'Oliveiro wrote: Either there are enough people using it to care about it, in which case somebody in the community will fix it, it or there are not, in which case it's not worth bothering with. That's EXACTLY the same as the proprietary software world. No it's not. A proprietary product can have lots of users who care about it, yet the vendor can't be bothered keeping it up to date any more. For instance, it was estimated that there were 40 million people still using Windows 98 when Microsoft announced an end to support. You don't get that with open-source products. -- http://mail.python.org/mailman/listinfo/python-list
Why bool( object )?
What is the rationale for considering all instances true of a user- defined type? Is it strictly a practical stipulation, or is there something conceptually true about objects? ''' object.__bool__(self) If a class defines neither __len__() nor __bool__(), all its instances are considered true. ''' This makes it so all objects except False, None, 0, and empty containers are true by default. I am not convinced that 'if a generic object' should have any meaning; it should probably throw an exception. Is it part of Python's look and feel or its mentality? Is it part of the Zen? Certainly other ideal types can't be cast from generic objects, so why booleans? Is it an ineffable component of the author's vision for the language? I think that giving arbitrary syntactic constructs meaning is just space-filler. It's worse than syntactic sugar, it's semantic sugar. Why not assign meanings willy- nilly to other random juxtapositions of tokens? -- http://mail.python.org/mailman/listinfo/python-list
Re: Thread-killing, round 666 (was Re: Lisp mentality vs. Python mentality)
In article 9a827369-b36f-4a86-870a-e5a505e34...@q33g2000pra.googlegroups.com, Vsevolod vselo...@gmail.com wrote: On Apr 27, 8:18 pm, a...@pythoncraft.com (Aahz) wrote: If you want to talk about Python and problems you're running into, you should start a new thread. I'm not at that level of proficiency with the language. I believe most of my technical problems are connected with lack of knowledge or experience, not the language's features. While conceptual problems seem futile to discuss. There's another saying: when in Rome do as the Romans do c.l.py isn't just for the experts; if you have a question along the lines of here's something I do in Lisp, how do I do it in Python?, you're entirely on-topic. Also, most of us are happy to explain why Python does things in certain ways -- as with Lisp, the more you wrap your mind into the Python Way, the easier you'll find your work. Note that neither of these is why isn't Python more like Lisp?, that's where you get into futility territory. ;-) -- Aahz (a...@pythoncraft.com) * http://www.pythoncraft.com/ If you think it's expensive to hire a professional to do the job, wait until you hire an amateur. --Red Adair -- http://mail.python.org/mailman/listinfo/python-list
Re: Why bool( object )?
On Mon, Apr 27, 2009 at 11:11 PM, Aaron Brady castiro...@gmail.com wrote: What is the rationale for considering all instances true of a user- defined type? Is it strictly a practical stipulation, or is there something conceptually true about objects? ''' object.__bool__(self) If a class defines neither __len__() nor __bool__(), all its instances are considered true. ''' This makes it so all objects except False, None, 0, and empty containers are true by default. I am not convinced that 'if a generic object' should have any meaning; it should probably throw an exception. Is it part of Python's look and feel or its mentality? Is it part of the Zen? Certainly other ideal types can't be cast from generic objects, so why booleans? Python simply defines a False value as: - None - False - 0 - An empty sequence - An empty mapping - If an instance defines itself as false via either __nonzero__ or __len__() with either method returning False. Anything else is simply True. These simple rules define Python's view of True or False. Any object is free to define its own Truthfulness or Falseness as it sees fit. But in general, these rules are extremely useful I think in the Pythonic realm of Practicality beats Purity. It allows and encourages you to write expressions like if thing instead of if thing == True or if thing is True which enhance readability, IMHO. Being able to ask, Is this list empy as if not lst instead of if len(lst) == 0 is a highly useful property in expressiveness and usefulness. For user defined classes it just defaults to assuming True.. but that class is free to define its own truthfulness how it sees fit. --S -- http://mail.python.org/mailman/listinfo/python-list
Re: Why bool( object )?
Aaron Brady wrote: What is the rationale for considering all instances true of a user- defined type? User-defined objects (or type) can override .__len__() [usually container types] or .__nonzero__() to make bool() returns False. Is it strictly a practical stipulation, or is there something conceptually true about objects? Objects are true unless they define themself as false. The practical implication is we can do this: def foo(args = None): if args: ... In python all objects are true except: None, False, 0/0L/0.0/0j, empty sequence or container, and on objects that defines .__len__() or .__nonzero__() that returns 0 or False. ''' object.__bool__(self) If a class defines neither __len__() nor __bool__(), all its instances are considered true. ''' This makes it so all objects except False, None, 0, and empty containers are true by default. I am not convinced that 'if a generic object' should have any meaning; it should probably throw an exception. Is it part of Python's look and feel or its mentality? Is it part of the Zen? Certainly other ideal types can't be cast from generic objects, so why booleans? Is it an ineffable component of the author's vision for the language? I think that giving arbitrary syntactic constructs meaning is just space-filler. It's worse than syntactic sugar, it's semantic sugar. Why not assign meanings willy- nilly to other random juxtapositions of tokens? It's part of the design decision. In almost all cases (in any language), a so-called Design Decision is rather random and prone to subjective judgment, just as the decision to make bool(int) returns False only on 0, -1, or for all negative values; whether to make bool(100) and exception or True; or round() rounds down or up or even-odd; or the use of brackets vs. indentation; or whether to treat empty list as True or False. -- http://mail.python.org/mailman/listinfo/python-list
Re: Why bool( object )?
On Mon, Apr 27, 2009 at 11:11 PM, Aaron Brady castiro...@gmail.com wrote: What is the rationale for considering all instances true of a user- defined type? Is it strictly a practical stipulation, or is there something conceptually true about objects? ''' object.__bool__(self) If a class defines neither __len__() nor __bool__(), all its instances are considered true. ''' This makes it so all objects except False, None, 0, and empty containers are true by default. I am not convinced that 'if a generic object' should have any meaning; it should probably throw an exception. Is it part of Python's look and feel or its mentality? Is it part of the Zen? Certainly other ideal types can't be cast from generic objects, so why booleans? Is it an ineffable component of the author's vision for the language? I think that giving arbitrary syntactic constructs meaning is just space-filler. It's worse than syntactic sugar, it's semantic sugar. Why not assign meanings willy- nilly to other random juxtapositions of tokens? I believe the justification is that in the case of objects with otherwise undefined truth, it effectively serves as a test for non-None-ness, which makes some sense and is apparently more useful in practice than throwing an exception. It was obviously a design decision made by the PSU, probably for practicality over purity reasons; indeed, they could reasonably have chose to make it throw an exception in such cases, but the current behavior is also reasonable and justifiable. For comparison, some other languages use a similar definition of truth (if you can't show it's false, then it's true), such as Lisp/Scheme and Ruby (if it's not equal to #f/false or nil, then it's true). Admittedly, it's not a direct comparison since Python has fancier semantics, but it's somewhat similar. Cheers, Chris -- http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: Why bool( object )?
On Apr 28, 1:35 am, Lie Ryan lie.1...@gmail.com wrote: Aaron Brady wrote: What is the rationale for considering all instances true of a user- defined type? User-defined objects (or type) can override .__len__() [usually container types] or .__nonzero__() to make bool() returns False. Is it strictly a practical stipulation, or is there something conceptually true about objects? Objects are true unless they define themself as false. The practical implication is we can do this: def foo(args = None): if args: ... In python all objects are true except: None, False, 0/0L/0.0/0j, empty sequence or container, and on objects that defines .__len__() or .__nonzero__() that returns 0 or False. ''' object.__bool__(self) If a class defines neither __len__() nor __bool__(), all its instances are considered true. ''' This makes it so all objects except False, None, 0, and empty containers are true by default. I am not convinced that 'if a generic object' should have any meaning; it should probably throw an exception. Is it part of Python's look and feel or its mentality? Is it part of the Zen? Certainly other ideal types can't be cast from generic objects, so why booleans? Is it an ineffable component of the author's vision for the language? I think that giving arbitrary syntactic constructs meaning is just space-filler. It's worse than syntactic sugar, it's semantic sugar. Why not assign meanings willy- nilly to other random juxtapositions of tokens? It's part of the design decision. In almost all cases (in any language), a so-called Design Decision is rather random and prone to subjective judgment, just as the decision to make bool(int) returns False only on 0, -1, or for all negative values; whether to make bool(100) and exception or True; or round() rounds down or up or even-odd; or the use of brackets vs. indentation; or whether to treat empty list as True or False. Whether it's a good feature and whether it's a popular feature are two different things. (It's not always clear that the former is even real anyway.) I'm actually not sure that my question was /entirely/ scientifically motivated. Perhaps I'm expressing admiration (or maybe envy). Maybe I want to design a popular language too. If I was really being scientific, I would have been wondering, what is the balance of pros and cons of the decision? pros - cons = ? Is that an objective expression? Are there only measurable quantities in both operands? If it's a close call, I might not agree, or might not have followed the same experimental method. Trivially the answer is, 'the decision maker found sum( pros ) sum ( cons )'. Many arts and disciplines do guesswork to a degree in evaluating their 'sum( pros )', so perhaps I should expect a degree of variation in what the experts all say that quantity is. On a more idealist's level, perhaps I am asking the outside world what /my/ evaluation of 'sum( pros )' is. What's yours? -- http://mail.python.org/mailman/listinfo/python-list
Re: Web based application development using python
Calling mod_python a web framework is a bit of a stretch. if you want to work at that level though mod_wsgi is worth a look, on top of that you can put a range of frameworks such as repose, django, turbo gears etc.. T On Apr 28, 12:55 pm, Rahul r.warhe...@gmail.com wrote: 2) I have my web based application written using mod_python a. It should be more based on framework type. b. It should have all the features present in mod_python. These two goals conflict. You'll need to use your brain to discover what is best for your application. In general have all the features of and but better conflict. --Scott David Daniels scott.dani...@acm.org hi scott, i am getting more specific, is there any web development framework better than mod python which is easy to maintain. thanks rahul -- http://mail.python.org/mailman/listinfo/python-list
Re: Web based application development using python
1) Do you have any idea about web based support (like mod_python) provided by python.org (official web site) Details: - As we know mod_python is used for embeding python code into apache server. so, i want to know whether mod_python is officially supported by python.org or if there is other such framework for embeding python on web server Thanks, Rahul -- http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
Denis L schrieb:
Hello,
I'm experiencing odd errors on both windows and linux with the following
code:
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class Options(QDialog):
def __init__(self, values):
QDialog.__init__(self)
self.values = values
fooEdit = QLineEdit(values['foo'])
self.connect(fooEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('foo', value))
barEdit = QLineEdit(values['bar'])
self.connect(barEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('bar', value))
layout = QVBoxLayout()
layout.addWidget(fooEdit)
layout.addWidget(barEdit)
self.setLayout(layout)
def optionChanged(self, option, value):
self.values[option] = value
print self.values
def main(args):
app = QApplication(args)
values = dict(foo='', bar='')
dialog = Options(values)
dialog.show()
app.exec_()
if __name__ == '__main__':
main(sys.argv)
If I type a character in fooEdit, another character in barEdit, and then
delete the character from barEdit I get an unhandled win32 exception occured
in python.exe on windows and segfault on linux.
If I type a character in fooEdit, delete it, and then type a character in
barEdit I get:
{'foo': PyQt4.QtCore.QString(u'a'), 'bar': ''}
{'foo': PyQt4.QtCore.QString(u''), 'bar': ''}
{'foo': Traceback (most recent call last):
File L:\home\dev\python\test.py, line 17, in lambda
lambda value: self.optionChanged('bar', value))
File L:\home\dev\python\test.py, line 27, in optionChanged
print self.values
MemoryError
I'm using Python 2.5.4 and PyQt 4.4.3-1
As the documentation of pyqt clearly states, connecting signals doesn't
increment the refcount on a passed slot, thus
you need to keep a reference to your slots around.
Diez
--
http://mail.python.org/mailman/listinfo/python-list
Re: Why bool( object )?
On Mon, 27 Apr 2009 23:11:11 -0700, Aaron Brady wrote:
What is the rationale for considering all instances true of a user-
defined type? Is it strictly a practical stipulation, or is there
something conceptually true about objects?
Seven years ago, in an attempt to convince Guido *not* to include
booleans in Python, Laura Creighton wrote a long, detailed post
explaining her opposition.
At the heart of her argument is the observation that Python didn't need
booleans, at least not the ints-in-fancy-hats booleans that we've ended
up with, because Python already made a far more useful and fundamental
distinction: between Something and Nothing.
http://groups.google.com/group/comp.lang.python/msg/2de5e1c8384c0360?hl=en
All objects are either Something or Nothing. The instances of some
classes are always Something, just as the instances of some classes are
always Nothing. By default, instances are Something, unless __nonzero__
returns False, or __len__ returns 0, then they are Nothing.
In a boolean (or truth) context, Something and Nothing behave like True
and False in languages with real booleans:
if obj:
print I am Something
else:
print I am Nothing
To steal an idiom from Laura: Python has a float-shaped Nothing 0.0, a
list-shaped Nothing [], a dict-shaped Nothing {}, an int-shaped Nothing
0, a singleton Nothing None, and so forth. It also has many corresponding
Somethings.
All bool() does is convert Something or Nothing into a canonical form,
the subclassed ints True and False.
I'm not sure whether Guido ever used the terms Something vs Nothing when
describing Python's truth-testing model, but it is clearly there, at the
heart of Python. Python didn't even get a boolean type until version 2.3.
--
Steven
--
http://mail.python.org/mailman/listinfo/python-list
Web framework for embedded system
I'm looking for a lightweight web-framework for an embedded system. The system is running a realtime linux-variant on a 200 MHz ARM processor, Python reports a performance of around 500 pystones. The web application will not be too fancy, no databases involved for example, but it will need to control some simple peripherals (some parallel in/out, some dacs) attached to the system. It should provide a user interface showing the current state and allowing to manipulate it via a browser, and I will probably need to support some rpc as well. Does this sound sensible at all? Any suggestions? Thomas -- http://mail.python.org/mailman/listinfo/python-list
sorted() erraticly fails to sort string numbers
I would be very interested in a logical explanation why this happens on python 2.5.1: In order to sort an etree by the .text value of one child, I adapted this snippet from effbot.org: import xml.etree.ElementTree as ET tree = ET.parse(data.xml) def getkey(elem): return elem.findtext(number) container = tree.find(entries) container[:] = sorted(container, key=getkey) tree.write(new-data.xml) While working with a moderately sized xml file (2500 entries to sort by), I found that a few elements were not in order. It seems that numbers with seven digits were sorted correctly, while those with six digits were just added at the end. I fixed the problem by converting the numbers to int in the callback: def getkey(elem): return int(elem.findtext(number)) So to my naive mind, it seems as if there was some error with the sorted() function. Would anyone be as kind as to explain why it could be happening? Thanks in advance! -- http://mail.python.org/mailman/listinfo/python-list
Re: Presentation software for Python code
Neal Becker wrote: IPython offers something similar for giving demos. I've found that very useful in the past. Really? Any pointers? http://ipython.scipy.org/doc/manual/html/api/generated/IPython.demo.html -- http://mail.python.org/mailman/listinfo/python-list
Re: sorted() erraticly fails to sort string numbers
On Tue, Apr 28, 2009 at 9:47 AM, uuid m8r-r1c6...@mailinator.com wrote: I would be very interested in a logical explanation why this happens on python 2.5.1: In order to sort an etree by the .text value of one child, I adapted this snippet from effbot.org: import xml.etree.ElementTree as ET tree = ET.parse(data.xml) def getkey(elem): return elem.findtext(number) container = tree.find(entries) container[:] = sorted(container, key=getkey) tree.write(new-data.xml) While working with a moderately sized xml file (2500 entries to sort by), I found that a few elements were not in order. It seems that numbers with seven digits were sorted correctly, while those with six digits were just added at the end. I fixed the problem by converting the numbers to int in the callback: def getkey(elem): return int(elem.findtext(number)) So to my naive mind, it seems as if there was some error with the sorted() function. Would anyone be as kind as to explain why it could be happening? Thanks in advance! When sorting strings, including strings that represent numbers, sorting is done alphabetically. In this alphabetical order the numbers are all ordered the normal way, so two numbers with the same number of digits will be sorted the same way, but any number starting with 1 will come before any number starting with 2, whether they denote units, tens, hundreds or millions. Thus: 1 15999 16 2 -- André Engels, andreeng...@gmail.com -- http://mail.python.org/mailman/listinfo/python-list
Memory leak on python 2.5 if using str(dict(a='a'))
Hi, all.
I use guppy-pe to identify this issue in my program. The resources links are
all embedded in source code already.
I developed a test case for your convenience and attached the log. Any gurus
help out here? It's really python internal stuff which I can't easily peek into.
Thanks,
Benjamin
test_tuple_and_dict.py
Description: Binary data
TEST4
{'a': 'a_value', 'b': 'b_value'}
Partition of a set of 5 objects. Total size = 1064 bytes.
Index Count % Size % Cumulative % Kind (class / dict of class)
0 2 40 864 81 864 81 types.FrameType
1 1 20 136 13 1000 94 dict (no owner)
2 1 20 32 3 1032 97 list
3 1 20 32 3 1064 100 str
=0=
Set of 2 types.FrameType objects. Total size = 864 bytes.
Index Size % Cumulative % Name at Address
0 448 51.9 448 51.9 heap at 0x822c2fc
1 416 48.1 864 100.0 profileHeap at 0x824ddd4
--0--
frame object at 0x822c2fc
=1=
Set of 1 dict (no owner) object. Total size = 136 bytes.
Index Size % Cumulative % Address*Length
0 136 100.0 136 100.0 0x828b68c*1
--0--
{'Py_Repr': [{...}, [...]]}
=2=
Set of 1 list object. Total size = 32 bytes.
Index Size % Cumulative % Address*Length
0 32 100.032 100.0 0x826b58c*0
--0--
[[...]]
=3=
Set of 1 str object. Total size = 32 bytes.
Index Size % Cumulative % Representation (limited)
0 32 100.032 100.0 'Py_Repr'
--0--
Py_Repr
TEST5
a a_value
b b_value
Partition of a set of 2 objects. Total size = 736 bytes.
Index Count % Size % Cumulative % Kind (class / dict of class)
0 2 100 736 100 736 100 types.FrameType
=0=
Set of 2 types.FrameType objects. Total size = 736 bytes.
Index Size % Cumulative % Name at Address
0 372 50.5 372 50.5 profileHeap at 0x824fc94
1 364 49.5 736 100.0 heap at 0x82edc04
--0--
frame object at 0x824fc94
TEST6
Partition of a set of 2 objects. Total size = 864 bytes.
Index Count % Size % Cumulative % Kind (class / dict of class)
0 2 100 864 100 864 100 types.FrameType
=0=
Set of 2 types.FrameType objects. Total size = 864 bytes.
Index Size % Cumulative % Name at Address
0 448 51.9 448 51.9 heap at 0x822c2fc
1 416 48.1 864 100.0 profileHeap at 0x824ddd4
--0--
frame object at 0x822c2fc
--
http://mail.python.org/mailman/listinfo/python-list
Re: Web based application development using python
Rahul wrote: 1) Do you have any idea about web based support (like mod_python) provided by python.org (official web site) Details: - As we know mod_python is used for embeding python code into apache server. so, i want to know whether mod_python is officially supported by python.org or if there is other such framework for embeding python on web server Forget about mod_python, everything else is better. This list (the first result upon googling for python web frameworks) is actually up to date, and a good start. http://wiki.python.org/moin/WebFrameworks Just don't ask which one is best for everything, or which one is The Official Standard Way Of Doing Things. -- http://mail.python.org/mailman/listinfo/python-list
Re: sorted() erraticly fails to sort string numbers
I am at the same time impressed with the concise answer and disheartened by my inability to see this myself. My heartfelt thanks! On 2009-04-28 10:06:24 +0200, Andre Engels andreeng...@gmail.com said: When sorting strings, including strings that represent numbers, sorting is done alphabetically. In this alphabetical order the numbers are all ordered the normal way, so two numbers with the same number of digits will be sorted the same way, but any number starting with 1 will come before any number starting with 2, whether they denote units, tens, hundreds or millions. Thus: 1 15999 16 2 -- http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
On Tue, 28 Apr 2009 03:53:34 +0200, Denis L n...@spam.com wrote:
Hello,
I'm experiencing odd errors on both windows and linux with the following
code:
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class Options(QDialog):
def __init__(self, values):
QDialog.__init__(self)
self.values = values
fooEdit = QLineEdit(values['foo'])
self.connect(fooEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('foo', value))
barEdit = QLineEdit(values['bar'])
self.connect(barEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('bar', value))
layout = QVBoxLayout()
layout.addWidget(fooEdit)
layout.addWidget(barEdit)
self.setLayout(layout)
def optionChanged(self, option, value):
self.values[option] = value
print self.values
def main(args):
app = QApplication(args)
values = dict(foo='', bar='')
dialog = Options(values)
dialog.show()
app.exec_()
if __name__ == '__main__':
main(sys.argv)
If I type a character in fooEdit, another character in barEdit, and then
delete the character from barEdit I get an unhandled win32 exception
occured
in python.exe on windows and segfault on linux.
If I type a character in fooEdit, delete it, and then type a character in
barEdit I get:
{'foo': PyQt4.QtCore.QString(u'a'), 'bar': ''}
{'foo': PyQt4.QtCore.QString(u''), 'bar': ''}
{'foo': Traceback (most recent call last):
File L:\home\dev\python\test.py, line 17, in lambda
lambda value: self.optionChanged('bar', value))
File L:\home\dev\python\test.py, line 27, in optionChanged
print self.values
MemoryError
I'm using Python 2.5.4 and PyQt 4.4.3-1
Thanks in advance for any help.
Works fine for me with current versions.
Phil
--
http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
On Tue, 28 Apr 2009 09:35:31 +0200, Diez B. Roggisch
de...@nospam.web.de
wrote:
Denis L schrieb:
Hello,
I'm experiencing odd errors on both windows and linux with the following
code:
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class Options(QDialog):
def __init__(self, values):
QDialog.__init__(self)
self.values = values
fooEdit = QLineEdit(values['foo'])
self.connect(fooEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('foo', value))
barEdit = QLineEdit(values['bar'])
self.connect(barEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('bar', value))
layout = QVBoxLayout()
layout.addWidget(fooEdit)
layout.addWidget(barEdit)
self.setLayout(layout)
def optionChanged(self, option, value):
self.values[option] = value
print self.values
def main(args):
app = QApplication(args)
values = dict(foo='', bar='')
dialog = Options(values)
dialog.show()
app.exec_()
if __name__ == '__main__':
main(sys.argv)
If I type a character in fooEdit, another character in barEdit, and then
delete the character from barEdit I get an unhandled win32 exception
occured
in python.exe on windows and segfault on linux.
If I type a character in fooEdit, delete it, and then type a character
in
barEdit I get:
{'foo': PyQt4.QtCore.QString(u'a'), 'bar': ''}
{'foo': PyQt4.QtCore.QString(u''), 'bar': ''}
{'foo': Traceback (most recent call last):
File L:\home\dev\python\test.py, line 17, in lambda
lambda value: self.optionChanged('bar', value))
File L:\home\dev\python\test.py, line 27, in optionChanged
print self.values
MemoryError
I'm using Python 2.5.4 and PyQt 4.4.3-1
As the documentation of pyqt clearly states, connecting signals doesn't
increment the refcount on a passed slot, thus
you need to keep a reference to your slots around.
But it does increase the refcount for lambda slots.
Phil
--
http://mail.python.org/mailman/listinfo/python-list
Re: python setup ?
Xavier Maillard wrote: Hi Xavier Maillard x...@gnu.org writes: I am starting to do some work with python. I am looking for options/setups to introduce into my .emacs file to have the best experience possible with this scripting language. Where should I start ? I personnaly use python-mode.el that is much better than python.el (that come with emacs). In what is it better ? I use also ipython as python shell that integrate fine in emacs. Phew, how many new dependances should I install in order to have something simple to use ? :) I thought python was something for beginners, it is not. I find it easier to play lisp... Xavier Hi Xavier, as its well known, you are not a beginner with Emacs, please permit to take your comment as occasion: Your question and experience with Emacs and Python reflects IMHO some general strength and likewise present limitation. The strength is, clearly: with that many files out there, that many people who wrote already something for python, with some Emacs Lisp knowledge you'll be able to install a reasonable environment. OTOH: how many people did that already, spent hours to collect and adapt utilities from the net? And afterwards? If we take together all this time from users configuring an python-environment, we could probably get more useful results from it. So there is a lose of time. Can we do better? ... :) One thing, thats to realize IMO: times are gone where one person with some knowledge of a language may write a mode and thats it. Even maintaining it alone seems to surpass any personal capacity. If we want to keep path, we have to establish developer-groups caring for a language. That happened already with C-modes AFAIS. We need that for any major language. Concerning python, we have enough man-power to perform excellent things. To the extent, user have to do `M-x python,' and an environment with all up-to-date debugging facilities gets installed. No question its great whats done at http://www.emacswiki.org/emacs/PythonMode Emacswiki was helpful many times for me. However, for pure development issues, designed platforms like Launchpad seem more suitable for the purpose for me. Beside excellent bazaar behind, lets mention its email- and bugreport integration. As it happens we have with Barry Warsaw not just an experienced Emacs Lisper, but a python core developer with its python-mode account: we should try our chance to proceed with his gentle help occasionally. AFAIS we need tailored accounts, where we maintain flavours of possible environments, learning and lifting from each other, enabling distributions to select and pull for delivering. So far Andreas -- http://bazaar.launchpad.net/~a-roehler/python-mode/python-mode.el/ https://code.launchpad.net/s-x-emacs-werkstatt/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Web framework for embedded system
Thomas Heller wrote: I'm looking for a lightweight web-framework for an embedded system. The system is running a realtime linux-variant on a 200 MHz ARM processor, Python reports a performance of around 500 pystones. The web application will not be too fancy, no databases involved for example, but it will need to control some simple peripherals (some parallel in/out, some dacs) attached to the system. It should provide a user interface showing the current state and allowing to manipulate it via a browser, and I will probably need to support some rpc as well. Does this sound sensible at all? Any suggestions? I'd try first what I know best. In my case Django. Despite the restricted hardware, it might just work fine because you'll only use a tiny fraction of it. If this doesn't work because of CPU or memory requirements, I'd next try to build my own using components like - CherryPy for the web server, it should also be able to handle your (XML)RPC requirements - some templating language like Mako (my favourite) It doesn't sound like you need much more. You could even build upon wsgiref, string.Template and the XMLRPC stuff in the standard library, but that's for people who like tinkering ;-) -- Gerhard -- http://mail.python.org/mailman/listinfo/python-list
Re: Lisp mentality vs. Python mentality
On Tue, 28 Apr 2009 02:00:22 -0300, namekuseijin wrote: Dan Sommers wrote: On Mon, 27 Apr 2009 07:57:00 +0300, Ciprian Dorin, Craciun wrote: I agree with your opinion about keeping the abstraction layers shallow, but in my view high-order and helper functions do not comprise a new abstraction layer. For example in Lisp, using map, reduce (fold), or any other high-order function is just like using for, or while in a normal imperative language. If I hit a call to map or to reduce, I've hit the bottom: map and reduce are defined by Lisp and not by the programmer. You truly don't know Lisp. *Everything* in Lisp can be _redefined_ and if you can't do something conveniently that way, you can use a _macro_ to implement convenient new syntax for it. Yes, I agree: Python and Lisp are extremely dynamic languages. I *can* redefine map, reduce, +, and other operators and functions, but I know better. When is the last time you examined someone else's code, and asked them what their map function did (in Lisp or in Python)? -- Dan Sommers A death spiral goes clock- http://www.tombstonezero.net/dan/ wise north of the equator. Atoms are not things. -- Werner Heisenberg -- Dilbert's PHB -- http://mail.python.org/mailman/listinfo/python-list
Re: Restart generator when it is exhausted.
On Tue, Apr 28, 2009 at 2:54 AM, Lacrima lacrima.ma...@gmail.com wrote: Hello! I am quite new to Python and I have maybe simple (or maybe not) question. Is it possible to restart generator when it is exhausted? No. You have to make a new instance of the generator. What should I do to get the initial state of g? So if I do again g.next () I receive 'a'. g = (i for i in a) #that is, make a fresh generator instance If it is not possible what are common techniques to use iterator or generator objects that allow restarting when it is needed? There's itertools.cycle() -- http://docs.python.org/library/itertools.html#itertools.cycle Cheers, Chris -- http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: mailbox.mbox.add() sets access time as well as modification time
Lawrence D'Oliveiro l...@geek-central.gen.new_zealand wrote: In message jo2dnwpluopxvwjunz2dnuvz_qudn...@posted.usinternet, Grant Edwards wrote: On 2009-04-26, Lawrence D'Oliveiro l...@geek-central.gen.new_zealand wrote: In message _vqdnf6pny1gymzunz2dnuvz_qcdn...@posted.visi, Grant Edwards wrote: ... if one didn't care about backwards-compatiblity with old e-mail apps, then one would use a less broken mailbox format like maildir. It's only in the proprietary-software world that we need to worry about backward compatibility with old, obsolete software that the vendors cannot or will not fix. In the Free Software world, we fix the software to bring it up to date. Who's we? Are you volunteering to fix all of the MUAs and MTAs out there that have mbox code in them that do follow the rules to make them compatible with _one_ broken library module? All the MUAs and MTAs I'm aware of that are worth bothering about have the option to support maildir format these days. Yes, but as I explained earlier in this thread there are reasons why one might want to stay with mbox. I use mutt which can quite happily cope with either mbox or maildir (and some other formats), it can even work with a mix of mailbox types. I've used mutt for several years now and have tried to move to maildir more than once and have always returned to mbox because the disadvantages of maildir outweigh the benefits (for me). Currently I run mutt on a remote server where I have to use maildir because their file systems are mounted noatime. I am moving to reading mail on my own Linux box just because I want to get back to mbox, this python issue is about the only thing I have to overcome before I have what I want. -- Chris Green -- http://mail.python.org/mailman/listinfo/python-list
Using ascii numbers in regular expression
Hi, How can I use the ascii number of a character in a regular expression (module re) instead of the character itself? Thanks very much -- http://mail.python.org/mailman/listinfo/python-list
screen scraping with Python?
Hi Friends, Please let me know whether VT100 (Screen scrapping) emulation is possible or not. If screen scrapping / VT100 emulation is possible, please let me know how to do it. I will be happier, if you can provide me steps and sample codes. I am a beginner in python. So kindly help me by letting me know about the possibilities. EXPECTING THE REPLY MAIL Thanks Regards, Arun FoneNet : 390-13359 Mobile: 9884471702 This email and any attachments are confidential and may also be privileged. If you are not the addressee, do not disclose, copy, circulate or in any other way use or rely on the information contained in this email or any attachments. If received in error, notify the sender immediately and delete this email and any attachments from your system. Emails cannot be guaranteed to be secure or error free as the message and any attachments could be intercepted, corrupted, lost, delayed, incomplete or amended. Standard Chartered PLC and its subsidiaries do not accept liability for damage caused by this email or any attachments and may monitor email traffic. Standard Chartered PLC is incorporated in England with limited liability under company number 966425 and has its registered office at 1 Aldermanbury Square, London, EC2V 7SB. Standard Chartered Bank (SCB) is incorporated in England with limited liability by Royal Charter 1853, under reference ZC18. The Principal Office of SCB is situated in England at 1 Aldermanbury Square, London EC2V 7SB. In the United Kingdom, SCB is authorised and regulated by the Financial Services Authority under FSA register number 114276. If you are receiving this email from SCB outside the UK, please click http://www.standardchartered.com/global/email_disclaimer.html to refer to the information on other jurisdictions. -- http://mail.python.org/mailman/listinfo/python-list
suggestion on a complicated inter-process communication
Hello friends, I have a little messy situation on IPC. Please if you can, give me some suggestion on how to implement. Thanks a lot! - denotes create MainProcess - Process1 - Process3 (from os.system) | - Process2 (from os.system) - Process4 (from os.system) -Process5 I would like to make the communication between Process1 and Process5. Process1 needs Process5's output to provide argument to generate Process3, and in turn Process5 needs to wait Process3 finished. Thank you very much if you can give a hint. -- http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
On Tue, 28 Apr 2009 11:18:31 +0200, Diez B. Roggisch de...@nospam.web.de wrote: As the documentation of pyqt clearly states, connecting signals doesn't increment the refcount on a passed slot, thus you need to keep a reference to your slots around. But it does increase the refcount for lambda slots. Has that changed? It has been a while, but I've been bitten by this before, so I was pretty sure about my answer. Support for lambda slots was add in PyQt v4.1.1 (released December 2006). Phil -- http://mail.python.org/mailman/listinfo/python-list
desperately looking for a howto on running my wxPython app on Vista
python 2.6, py2exe and Vista do not make a happy set. Unfortunately I am in dire need to launch my app not only on WinXP but also on Vista. I need 2.6 because of a number of support packages I am using and some of which I am compiling myself (and python 2.5 needs a version of visual studio that is no longer available.) I can find all kinds of advice and discussions with google but I have yet to find a clear explanation on what a poor developer like me is supposed to do to get my python 2.6.2 , stackless, wxpython and all my (self-built) pyds to work happily on Vista. I am currently stuck on the infamous R6034 error but I understand that after that there may be another issue with certain wxPython functions. Can someone please point me to a howto on crafting the right Setup.py and manifests etc. to make this work? Paul -- http://mail.python.org/mailman/listinfo/python-list
Python 2.6 ImportError: cannot import name SSLType
I have built python 2.6.1 and 2.6.2 with ssl support (Redhat 3.4.6-9 / Openssl 0.9.8j). I am trying to use this with the Apache Qpid project but cannot bring up an ssl connection because the code relies on socket.SSLType which is missing from my build. The only references to SSLType I can find for python is that it is missing from the windows version which I am not using. I do not see what is going wrong. Any tips greatly appreciated. Roger -- http://mail.python.org/mailman/listinfo/python-list
Re: screen scraping with Python?
On Mon, 27 Apr 2009 12:28:31 +0530, Meenakshi, Arun Kumar arunkumar.meenak...@sc.com wrote: Hi Friends, Please let me know whether VT100 (Screen scrapping) emulation is possible or not. If screen scrapping / VT100 emulation is possible, please let me know how to do it. I will be happier, if you can provide me steps and sample codes. I am a beginner in python. So kindly help me by letting me know about the possibilities. EXPECTING THE REPLY MAIL Thanks Of course... VT-100 terminals were usually rs-232 devices connected at 9600 baud If you can write some python code talking to the serial port, you can easily read the data from the port... render it... and do whatever you need... If you are doing it over a network then you are using a terminal emulator. Many of the top name termninal emulators provide a programming api. If not.. go open source There are just many.. many different ways these days... depending on what platform and which terminal emulator you are using... David -- http://mail.python.org/mailman/listinfo/python-list
Restart generator when it is exhausted.
Hello! I am quite new to Python and I have maybe simple (or maybe not) question. Is it possible to restart generator when it is exhausted? For example: a = ['a', 'b', 'c'] g = (i for i in a) g.next() 'a' g.next() 'b' g.next() 'c' g.next() Traceback (most recent call last): File pyshell#31, line 1, in module g.next() StopIteration What should I do to get the initial state of g? So if I do again g.next () I receive 'a'. If it is not possible what are common techniques to use iterator or generator objects that allow restarting when it is needed? With regards, Max (sorry if my English isn't very proper) -- http://mail.python.org/mailman/listinfo/python-list
Re: Restart generator when it is exhausted.
On Apr 28, 1:04 pm, Chris Rebert c...@rebertia.com wrote: On Tue, Apr 28, 2009 at 2:54 AM, Lacrima lacrima.ma...@gmail.com wrote: Hello! I am quite new to Python and I have maybe simple (or maybe not) question. Is it possible to restart generator when it is exhausted? No. You have to make a new instance of the generator. What should I do to get the initial state of g? So if I do again g.next () I receive 'a'. g = (i for i in a) #that is, make a fresh generator instance If it is not possible what are common techniques to use iterator or generator objects that allow restarting when it is needed? There's itertools.cycle() --http://docs.python.org/library/itertools.html#itertools.cycle Cheers, Chris --http://blog.rebertia.com Chris, thanks a lot for the help! -- http://mail.python.org/mailman/listinfo/python-list
Efficient bits manipulation in Python
Hi: I have a bit-code :'1011011', how can I reverse it to '1101101'? Another question is I know how to transform the string '110' into integer 6, does anyone know how to transform integer 6 to a string '110'? Thank you very much:) -- Li -- Time is all we have and you may find one day you have less than you think -- http://mail.python.org/mailman/listinfo/python-list
RE: screen scraping with Python?
David, Thanks a ton for your swift reply. I will be more happy, if you could direct me with right API with which I can walk further. Regards, Arun FoneNet : 390-13359 Mobile: 9884471702 -Original Message- From: David Lyon [mailto:david.l...@preisshare.net] Sent: Tuesday, April 28, 2009 4:52 PM To: Meenakshi, Arun Kumar Cc: python-list@python.org Subject: Re: screen scraping with Python? On Mon, 27 Apr 2009 12:28:31 +0530, Meenakshi, Arun Kumar arunkumar.meenak...@sc.com wrote: Hi Friends, Please let me know whether VT100 (Screen scrapping) emulation is possible or not. If screen scrapping / VT100 emulation is possible, please let me know how to do it. I will be happier, if you can provide me steps and sample codes. I am a beginner in python. So kindly help me by letting me know about the possibilities. EXPECTING THE REPLY MAIL Thanks Of course... VT-100 terminals were usually rs-232 devices connected at 9600 baud If you can write some python code talking to the serial port, you can easily read the data from the port... render it... and do whatever you need... If you are doing it over a network then you are using a terminal emulator. Many of the top name termninal emulators provide a programming api. If not.. go open source There are just many.. many different ways these days... depending on what platform and which terminal emulator you are using... David This email and any attachments are confidential and may also be privileged. If you are not the addressee, do not disclose, copy, circulate or in any other way use or rely on the information contained in this email or any attachments. If received in error, notify the sender immediately and delete this email and any attachments from your system. Emails cannot be guaranteed to be secure or error free as the message and any attachments could be intercepted, corrupted, lost, delayed, incomplete or amended. Standard Chartered PLC and its subsidiaries do not accept liability for damage caused by this email or any attachments and may monitor email traffic. Standard Chartered PLC is incorporated in England with limited liability under company number 966425 and has its registered office at 1 Aldermanbury Square, London, EC2V 7SB. Standard Chartered Bank (SCB) is incorporated in England with limited liability by Royal Charter 1853, under reference ZC18. The Principal Office of SCB is situated in England at 1 Aldermanbury Square, London EC2V 7SB. In the United Kingdom, SCB is authorised and regulated by the Financial Services Authority under FSA register number 114276. If you are receiving this email from SCB outside the UK, please click http://www.standardchartered.com/global/email_disclaimer.html to refer to the information on other jurisdictions. -- http://mail.python.org/mailman/listinfo/python-list
RE: screen scraping with Python?
On Tue, 28 Apr 2009 16:57:18 +0530, Meenakshi, Arun Kumar arunkumar.meenak...@sc.com wrote: David, Thanks a ton for your swift reply. I will be more happy, if you could direct me with right API with which I can walk further. Twisted includes a vt102 API along with an in-memory emulator implementing many (but not all) of the features of the terminal. You can find the API documentation online: http://twistedmatrix.com/documents/current/api/twisted.conch.insults.html Jean-Paul -- http://mail.python.org/mailman/listinfo/python-list
Re: Efficient bits manipulation in Python
On Tue, Apr 28, 2009 at 7:26 AM, Li Wang li.wan...@gmail.com wrote: Hi: I have a bit-code :'1011011', how can I reverse it to '1101101'? Another question is I know how to transform the string '110' into integer 6, does anyone know how to transform integer 6 to a string '110'? Thank you very much:) Assuming that you are using 2.6: a = 0b1011011 print bin(a)[:1:-1] a = 6 print bin(a)[2:] - Max -- http://mail.python.org/mailman/listinfo/python-list
Re: Web based application development using python
On Apr 28, 1:02 pm, Marco Mariani ma...@sferacarta.com wrote: Rahul wrote: 1) Do you have any idea about web based support (like mod_python) provided by python.org (official web site) Details: - As we know mod_python is used for embeding python code into apache server. so, i want to know whether mod_python is officially supported by python.org or if there is other such framework for embeding python on web server Forget about mod_python, everything else is better. This list (the first result upon googling for python web frameworks) is actually up to date, and a good start. http://wiki.python.org/moin/WebFrameworks Just don't ask which one is best for everything, or which one is The Official Standard Way Of Doing Things. but i want to know which is the official standard recommended by python. -- http://mail.python.org/mailman/listinfo/python-list
Unknown Visual C++ error
hello, Anyone knows what this error message means ? Python 2.5.2 thanks, Stef -- http://mail.python.org/mailman/listinfo/python-list
Re: Using ascii numbers in regular expression
Thanks very much for your reply.
What I mean is that I would like to use the ascii number in a regular
expression pattern.
For instance, if I want to substitute the occurrences of character 'a' for
the character 'b' in a string, instead of doing this:
re.subn('a','b','')
I'd like to specify the ascii number of a (which is 97)
I tried converting 97 to hexadecimal (with hex()) and tried this
re.subn(''\0x61,'b','')
but it doesnt work.
I need this because I'm working on non printable characters.
Thanks a lot
On Tue, Apr 28, 2009 at 12:45 PM, Chris Rebert c...@rebertia.com wrote:
On Tue, Apr 28, 2009 at 4:05 AM, jorma kala jjk...@gmail.com wrote:
Hi,
How can I use the ascii number of a character in a regular expression
(module re) instead of the character itself?
Thanks very much
I refer you to the chr() and ord() built-in functions, which can
certainly be used to solve your problem, though they are not
regex-specific in application.
http://docs.python.org/library/functions.html
Cheers,
Chris
--
http://blog.rebertia.com
--
http://mail.python.org/mailman/listinfo/python-list
Re: Efficient bits manipulation in Python
I have a bit-code :'1011011', how can I reverse it to '1101101'? Another question is I know how to transform the string '110' into integer 6, does anyone know how to transform integer 6 to a string '110'? Thank you very much:) Assuming that you are using 2.6: a = 0b1011011 print bin(a)[:1:-1] a = 6 print bin(a)[2:] Thank you very much, that works:). - Max -- Li -- Time is all we have and you may find one day you have less than you think -- http://mail.python.org/mailman/listinfo/python-list
Re: Web based application development using python
On Apr 28, 7:50 pm, Rahul r.warhe...@gmail.com wrote: On Apr 28, 1:02 pm, Marco Mariani ma...@sferacarta.com wrote: Rahul wrote: 1) Do you have any idea about web based support (like mod_python) provided by python.org (official web site) Details: - As we know mod_python is used for embeding python code into apache server. so, i want to know whether mod_python is officially supported by python.org or if there is other such framework for embeding python on web server Forget about mod_python, everything else is better. This list (the first result upon googling for python web frameworks) is actually up to date, and a good start. http://wiki.python.org/moin/WebFrameworks Just don't ask which one is best for everything, or which one is The Official Standard Way Of Doing Things. but i want to know which is the official standard recommended by python. But there isn't There are a number of frameworks out there each with there own set of strengths and weaknesses, you shoul dbe looking at each ones vibrancy (community), suitablility for your application, etc... T T -- http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
As the documentation of pyqt clearly states, connecting signals doesn't increment the refcount on a passed slot, thus you need to keep a reference to your slots around. But it does increase the refcount for lambda slots. Has that changed? It has been a while, but I've been bitten by this before, so I was pretty sure about my answer. Diez -- http://mail.python.org/mailman/listinfo/python-list
Re: Why bool( object )?
Lie Ryan wrote: Aaron Brady wrote: What is the rationale for considering all instances true of a user- defined type? User-defined objects (or type) can override .__len__() [usually container types] or .__nonzero__() to make bool() returns False. Is it strictly a practical stipulation, or is there something conceptually true about objects? Objects are true unless they define themself as false. The practical implication is we can do this: def foo(args = None): if args: ... In python all objects are true except: None, False, 0/0L/0.0/0j, empty sequence or container, and on objects that defines .__len__() or ..__nonzero__() that returns 0 or False. ''' object.__bool__(self) If a class defines neither __len__() nor __bool__(), all its instances are considered true. ''' This makes it so all objects except False, None, 0, and empty containers are true by default. I am not convinced that 'if a generic object' should have any meaning; it should probably throw an exception. Is it part of Python's look and feel or its mentality? Is it part of the Zen? Certainly other ideal types can't be cast from generic objects, so why booleans? Is it an ineffable component of the author's vision for the language? I think that giving arbitrary syntactic constructs meaning is just space-filler. It's worse than syntactic sugar, it's semantic sugar. Why not assign meanings willy- nilly to other random juxtapositions of tokens? It's part of the design decision. In almost all cases (in any language), a so-called Design Decision is rather random and prone to subjective judgment, just as the decision to make bool(int) returns False only on 0, -1, or for all negative values; whether to make bool(100) and exception or True; or round() rounds down or up or even-odd; or the use of brackets vs. indentation; or whether to treat empty list as True or False. I'm puzzled by the last sentence: *** Python 2.6.2 (r262:71605, Apr 14 2009, 22:40:02) [MSC v.1500 32 bit (Intel)] on win32. *** bool(0) False bool(-1) True bool(-100) True Colin W. -- http://mail.python.org/mailman/listinfo/python-list
Connecting/talking to OpenOffice Base files
Hi, I was wondering if the python interpretor can talk to files with extension *.odb (OpenOffice Base files). They are like flat database files, similar to Microsoft Access files. I want to store data into them as well as extract data out of them. --deostroll -- http://mail.python.org/mailman/listinfo/python-list
Re: Using ascii numbers in regular expression
On Tue, Apr 28, 2009 at 4:58 AM, jorma kala jjk...@gmail.com wrote:
Thanks very much for your reply.
What I mean is that I would like to use the ascii number in a regular
expression pattern.
For instance, if I want to substitute the occurrences of character 'a' for
the character 'b' in a string, instead of doing this:
re.subn('a','b','')
I'd like to specify the ascii number of a (which is 97)
I tried converting 97 to hexadecimal (with hex()) and tried this
You should go the more direct route, as my function recommendation implied:
assert chr(97) == a
re.subn(chr(97),'b','')
Cheers,
Chris
--
http://blog.rebertia.com
--
http://mail.python.org/mailman/listinfo/python-list
Re: Using ascii numbers in regular expression
On Tue, Apr 28, 2009 at 4:05 AM, jorma kala jjk...@gmail.com wrote: Hi, How can I use the ascii number of a character in a regular expression (module re) instead of the character itself? Thanks very much I refer you to the chr() and ord() built-in functions, which can certainly be used to solve your problem, though they are not regex-specific in application. http://docs.python.org/library/functions.html Cheers, Chris -- http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: Why bool( object )?
In message 54cb7f8a- fef4-4bf8-8054-16dc9b5c8...@d2g2000pra.googlegroups.com, Aaron Brady wrote: What is the rationale for considering all instances true of a user- defined type? It's a stupid idea, and there seem to be instances of users tripping over it here in comp.lang.python every week. -- http://mail.python.org/mailman/listinfo/python-list
Re: The whole story
Paul Hemans wrote: Hi Andrew, The reason I am using mapped objects is that I need to abstract from the database implementation allowing the replication to target a number of different platforms. This will definitely slow things down. have you looked at sqlalchemy's generic sql support? you can construct sql statements using python classes/functions called select, update etc and sqlalchemy automatically makes things work with different database implementations. it's not perfect, but i have the same code working with mysql and oracle, which covers quite a range :o) process a whole pile in memory and then (perhaps every 10,000 - when your memory is about to run out and start paging) flush the session. Under windows how can I tell when memory is about to run out? I guess there is no cross-platform solution to this. i don't know, sorry. Writing external files has all come about from a post titled Memory problems (garbage collection) by Carbon Man which I never got a resolution to. I was trying to execute gc.collect() when a process was complete because I was having huge problems with memory (though the problem still remains). If I stop at import schema There are 2524104 objects processed by gc.collect() you shouldn't need to call gc.collect(). when you write everything out to the database, if you have no other references to the objects, python will clean them up automatically. calling gc.collect() won't make any difference - python's gc already works just fine. if your memory use isn't going down then either (1) you are not writing out/flushing correctly (if you want i can check my code later today and tell you exactly what i do) or you are keeping references to your objects elsewhere (eg in a dictionary in the code you use to construct them). andrew -- http://mail.python.org/mailman/listinfo/python-list
Re: Restart generator when it is exhausted.
Lacrima lacrima.ma...@gmail.com wrote: If it is not possible what are common techniques to use iterator or generator objects that allow restarting when it is needed? The usual thing if you want to use the generator's output more than once would be to convert the generator to a list, then you can iterate over it as often as you want. a = ['a', 'b', 'c'] g = (i for i in a) restartable = list(g) If you want the output of the generator to potentially change each time you iterate then you need to create a new generator. -- Duncan Booth http://kupuguy.blogspot.com -- http://mail.python.org/mailman/listinfo/python-list
Re: Why bool( object )?
On Tue, Apr 28, 2009 at 2:22 PM, Colin J. Williams c...@ncf.ca wrote: Lie Ryan wrote: Aaron Brady wrote: What is the rationale for considering all instances true of a user- defined type? User-defined objects (or type) can override .__len__() [usually container types] or .__nonzero__() to make bool() returns False. Is it strictly a practical stipulation, or is there something conceptually true about objects? Objects are true unless they define themself as false. The practical implication is we can do this: def foo(args = None): if args: ... In python all objects are true except: None, False, 0/0L/0.0/0j, empty sequence or container, and on objects that defines .__len__() or ..__nonzero__() that returns 0 or False. ''' object.__bool__(self) If a class defines neither __len__() nor __bool__(), all its instances are considered true. ''' This makes it so all objects except False, None, 0, and empty containers are true by default. I am not convinced that 'if a generic object' should have any meaning; it should probably throw an exception. Is it part of Python's look and feel or its mentality? Is it part of the Zen? Certainly other ideal types can't be cast from generic objects, so why booleans? Is it an ineffable component of the author's vision for the language? I think that giving arbitrary syntactic constructs meaning is just space-filler. It's worse than syntactic sugar, it's semantic sugar. Why not assign meanings willy- nilly to other random juxtapositions of tokens? It's part of the design decision. In almost all cases (in any language), a so-called Design Decision is rather random and prone to subjective judgment, just as the decision to make bool(int) returns False only on 0, -1, or for all negative values; whether to make bool(100) and exception or True; or round() rounds down or up or even-odd; or the use of brackets vs. indentation; or whether to treat empty list as True or False. I'm puzzled by the last sentence: *** Python 2.6.2 (r262:71605, Apr 14 2009, 22:40:02) [MSC v.1500 32 bit (Intel)] on win32. *** bool(0) False bool(-1) True bool(-100) True Colin W. -- http://mail.python.org/mailman/listinfo/python-list bool has been defined thus in Python: False are: * False * None * empty containers, lists etc. * The number zero Everything else is true. -100 is not equal to zero, so its boolean value is True. -- André Engels, andreeng...@gmail.com -- http://mail.python.org/mailman/listinfo/python-list
Re: Connecting/talking to OpenOffice Base files
hi, On Tue, 2009-04-28 at 05:24 -0700, deostroll wrote: Hi, I was wondering if the python interpretor can talk to files with extension *.odb (OpenOffice Base files). They are like flat database files, similar to Microsoft Access files. I want to store data into them as well as extract data out of them. This is done either using ooolib if you want to do some simple read and write tasks or then use odfpy which is a complete library. I had asked the same question a few months back and come from the same path you are coming. But odfpy was initially difficult for me and would take a while to understand. It is a kind of wrapper around the xml structure of an odf document. happy hacking. Krishnakant. --deostroll -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
[ANN] pyOpenSSL 0.9
I'm happy to announce the release of pyOpenSSL 0.9. This release includes several new features and a very important bug fix: * APIs have been introduced to get and set the version of an X509 request * Contexts now support loading CA certificates for verification from a specified directory or from the platform's default certificate store * DTLS-related constants, OP_NO_QUERY_MTU, OP_COOKIE_EXCHANGE, and OP_NO_TICKET are now exposed * X509Extension now has the `get_short_name´ method for retrieving the short form of the extension type * It is now possible to create extensions which use any of the three possible OpenSSL implementation approaches * FILETYPE_TEXT can be used to dump keys, certificate, and CSRs in text format * Various compiler warnings have been fixed * A bug triggered by almost all uses of pyOpenSSL from multiple threads and leading to a crash has been fixed Many thanks to numerous people who contributed patches to this release. You can find pyOpenSSL 0.9 in the downloads area of the SourceForge project page: https://sourceforge.net/project/showfiles.php?group_id=31249 Please use Launchpad to file any bug reports: https://bugs.launchpad.net/pyopenssl Jean-Paul Calderone -- http://mail.python.org/mailman/listinfo/python-list
Re: Is there a maximum size to a Python program?
On 27 Apr, 05:01, Carbon Man dar...@nowhere.com wrote: I have a program that is generated from a generic process. It's job is to check to see whether records (replicated from another system) exist in a local table, and if it doesn't, to add them. I have 1 of these programs for every table in the database. Some people have discussed whether you need one or many programs. In practice, you're going to need to execute many tasks to process all your tables, and potentially this could mean generating many SQL statements, as I will describe below. [...] I am thinking that dynamically generating the programs to run might not be such a good idea. It would be a shame to drop it because the system needs to be generic and it runs from an XML file so the resulting code could be pretty complex, and I am new to Python. The program did generate a pyc so it was able to compile. Thoughts anyone? This problem sounds as if it could be solved adequately using only the database system, although I accept that sometimes some logic or additional processing could be done in Python. If I were to receive updates from a system, presumably as files, I'd want to bulk copy them into the database and then perform the necessary inserts using SQL. If the raw updates were not directly compatible with the database, perhaps because data representations might differ, then I would want to process them before doing the bulk copy. In other words, the workflow for a single table would look like this: 1. Obtain update files. 2. Process files in order to make the data compatible with the database. 3. Create temporary tables for the updates in the database. 4. Bulk copy the files into the temporary tables (using COPY or LOAD DATA commands). 5. Do the necessary inserts (where you have to either use the non- standard INSERT OR UPDATE or an INSERT involving a join between existing and temporary tables). 6. Drop the temporary tables (if not done automatically). Now, it's almost certain that the details of the above workflow would vary from table to table and from update to update. Even in the case where you don't have to process the files, you still need to copy the files into the database and to work with a different table each time. This is where generating something for each table is unavoidable, and one solution might be to have a generic template and to substitute the table name and update filename into that template as you process each table and its associated data. Whether you actually generate an SQL command file for each table, or whether you have a program issue the commands directly, is a matter of preference. Anyway, from what you've described, that's how I would approach this problem. Certainly, it's a lot more straightforward than dealing with object-relational abstractions in programs generated by other programs. Paul -- http://mail.python.org/mailman/listinfo/python-list
Re: Web framework for embedded system
On Apr 28, 3:43 am, Thomas Heller thel...@python.net wrote: I'm looking for a lightweight web-framework for an embedded system. The system is running a realtime linux-variant on a 200 MHz ARM processor, Python reports a performance of around 500 pystones. The web application will not be too fancy, no databases involved for example, but it will need to control some simple peripherals (some parallel in/out, some dacs) attached to the system. It should provide a user interface showing the current state and allowing to manipulate it via a browser, and I will probably need to support some rpc as well. Does this sound sensible at all? Any suggestions? Thomas You should definitely check out the SIMPL toolkit (http:// www.icanprogram.com/simpl). We have used this ultra lightweight toolkit in several embedded Linux projects. It will allow you to seamlessly connect your Python bits with bits more appropriately written in other languages like C. There is a hello world level tutorial on the Python-SIMPL capabilities (which includes a web CGI interface) at: http://www.icanprogram.com/06py/main.html If you have any questions about our SIMPL experiences don't hesitate to ask. bob -- http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
Phil Thompson p...@riverbankcomputing.com wrote in message
news:mailman.4664.1240907352.11746.python-l...@python.org...
On Tue, 28 Apr 2009 03:53:34 +0200, Denis L n...@spam.com wrote:
Hello,
I'm experiencing odd errors on both windows and linux with the following
code:
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class Options(QDialog):
def __init__(self, values):
QDialog.__init__(self)
self.values = values
fooEdit = QLineEdit(values['foo'])
self.connect(fooEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('foo', value))
barEdit = QLineEdit(values['bar'])
self.connect(barEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('bar', value))
layout = QVBoxLayout()
layout.addWidget(fooEdit)
layout.addWidget(barEdit)
self.setLayout(layout)
def optionChanged(self, option, value):
self.values[option] = value
print self.values
def main(args):
app = QApplication(args)
values = dict(foo='', bar='')
dialog = Options(values)
dialog.show()
app.exec_()
if __name__ == '__main__':
main(sys.argv)
If I type a character in fooEdit, another character in barEdit, and then
delete the character from barEdit I get an unhandled win32 exception
occured
in python.exe on windows and segfault on linux.
If I type a character in fooEdit, delete it, and then type a character in
barEdit I get:
{'foo': PyQt4.QtCore.QString(u'a'), 'bar': ''}
{'foo': PyQt4.QtCore.QString(u''), 'bar': ''}
{'foo': Traceback (most recent call last):
File L:\home\dev\python\test.py, line 17, in lambda
lambda value: self.optionChanged('bar', value))
File L:\home\dev\python\test.py, line 27, in optionChanged
print self.values
MemoryError
I'm using Python 2.5.4 and PyQt 4.4.3-1
Thanks in advance for any help.
Works fine for me with current versions.
Phil
I have noticed that if I do self.values[option] = QString(value)
instead of self.values[option] = value in optionChanged I don't get any
errors.
Is it perhaps not safe to keep the reference to the lambda QString argument?
--
http://mail.python.org/mailman/listinfo/python-list
Getting the dir from the other ancestor ?
hello, I have a class, derived from some user defined class (User_Defined_Ancestor) and some basic class (Basic_Ancestor). One of the major tasks of the Basic_Ancestor, is to hide all kinds of implementation details for the user, so the user can concentrate on the functional design. One of things I need to know are the methods and attributes of the Basic_Ancestor. Both classes are dynamic, i.e. attributes are added during run time. class Master ( User_Defined_Ancestor, Basic_Ancestor ) : def __init__ ( self, *args, **kwargs ) : Basic_Ancestor.__init__ ( self, *args, **kwargs ) . class Basic_Ancestor ( object ) : def __init__ ( self, ) : self.other = dir ( User_Defined_Ancestor ) def Get_Attributes ( self ) : return dir ( self ) - dir ( self.other ) Now the problem is, I don't know User_Defined_Ancestor in Basic_Ancestor. I can't pass it through the parameter list, because I use *args, **kwargs I possibly could use some global variable, but that's not my preference. Any other suggestions ? thanks, Stef Mientki -- http://mail.python.org/mailman/listinfo/python-list
Re: Getting the dir from the other ancestor ?
On 28 Apr, 15:01, Stef Mientki stef.mien...@gmail.com wrote: hello, I have a class, derived from some user defined class (User_Defined_Ancestor) and some basic class (Basic_Ancestor). One of the major tasks of the Basic_Ancestor, is to hide all kinds of implementation details for the user, so the user can concentrate on the functional design. One of things I need to know are the methods and attributes of the Basic_Ancestor. Both classes are dynamic, i.e. attributes are added during run time. class Master ( User_Defined_Ancestor, Basic_Ancestor ) : def __init__ ( self, *args, **kwargs ) : Basic_Ancestor.__init__ ( self, *args, **kwargs ) . class Basic_Ancestor ( object ) : def __init__ ( self, ) : self.other = dir ( User_Defined_Ancestor ) def Get_Attributes ( self ) : return dir ( self ) - dir ( self.other ) Now the problem is, I don't know User_Defined_Ancestor in Basic_Ancestor. I can't pass it through the parameter list, because I use *args, **kwargs I possibly could use some global variable, but that's not my preference. Any other suggestions ? thanks, Stef Mientki In anytime, if you do dir() in a class B, that extends a class A, you have all fields of A also. Example: class A: ...def a(self): ...return 0 class B(A): ...def b(self): ...return 5 dir(A) [., 'a'] dir(B) [.., 'a', 'b'] Hi. -- http://mail.python.org/mailman/listinfo/python-list
Re: mailbox.mbox.add() sets access time as well as modification time
On 2009-04-27, Lawrence D'Oliveiro l...@geek-central.gen.new_zealand wrote: In message gt3a7k$8d...@panix3.panix.com, Aahz wrote: In article gt0f2d$t5...@lust.ihug.co.nz, Lawrence D'Oliveiro l...@geek-central.gen.new_zealand wrote: It's only in the proprietary-software world that we need to worry about backward compatibility with old, obsolete software that the vendors cannot or will not fix. In the Free Software world, we fix the software to bring it up to date. Are you volunteering to maintain trn3.6? Either there are enough people using it to care about it, in which case somebody in the community will fix it, it or there are not, in which case it's not worth bothering with. Except _it's_not_broken_. It follows the established set of rules for manipulating mbox mailboxes. It follows the set of rules that all other mbox MUAs and MTAs use. Python's library is not following the rules, and your response is that the rest of the world should change? -- Grant Edwards grante Yow! GOOD-NIGHT, everybody at ... Now I have to go visi.comadminister FIRST-AID to my pet LEISURE SUIT!! -- http://mail.python.org/mailman/listinfo/python-list
Re: mailbox.mbox.add() sets access time as well as modification time
On 2009-04-27, Lawrence D'Oliveiro l...@geek-central.gen.new_zealand wrote: Who's we? Are you volunteering to fix all of the MUAs and MTAs out there that have mbox code in them that do follow the rules to make them compatible with _one_ broken library module? All the MUAs and MTAs I'm aware of that are worth bothering about have the option to support maildir format these days. That sure seems like a rather unhelpful response when somebody finds a bug in the standard library: 1) Don't use that module. 2) Change the rest of the world to work around Python's bug. -- Grant Edwards grante Yow! I've got an IDEA!! at Why don't I STARE at you visi.comso HARD, you forget your SOCIAL SECURITY NUMBER!! -- http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
On Tue, 28 Apr 2009 14:54:41 +0200, Denis L n...@spam.com wrote:
Phil Thompson p...@riverbankcomputing.com wrote in message
news:mailman.4664.1240907352.11746.python-l...@python.org...
On Tue, 28 Apr 2009 03:53:34 +0200, Denis L n...@spam.com wrote:
Hello,
I'm experiencing odd errors on both windows and linux with the
following
code:
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class Options(QDialog):
def __init__(self, values):
QDialog.__init__(self)
self.values = values
fooEdit = QLineEdit(values['foo'])
self.connect(fooEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('foo', value))
barEdit = QLineEdit(values['bar'])
self.connect(barEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('bar', value))
layout = QVBoxLayout()
layout.addWidget(fooEdit)
layout.addWidget(barEdit)
self.setLayout(layout)
def optionChanged(self, option, value):
self.values[option] = value
print self.values
def main(args):
app = QApplication(args)
values = dict(foo='', bar='')
dialog = Options(values)
dialog.show()
app.exec_()
if __name__ == '__main__':
main(sys.argv)
If I type a character in fooEdit, another character in barEdit, and
then
delete the character from barEdit I get an unhandled win32 exception
occured
in python.exe on windows and segfault on linux.
If I type a character in fooEdit, delete it, and then type a character
in
barEdit I get:
{'foo': PyQt4.QtCore.QString(u'a'), 'bar': ''}
{'foo': PyQt4.QtCore.QString(u''), 'bar': ''}
{'foo': Traceback (most recent call last):
File L:\home\dev\python\test.py, line 17, in lambda
lambda value: self.optionChanged('bar', value))
File L:\home\dev\python\test.py, line 27, in optionChanged
print self.values
MemoryError
I'm using Python 2.5.4 and PyQt 4.4.3-1
Thanks in advance for any help.
Works fine for me with current versions.
Phil
I have noticed that if I do self.values[option] = QString(value)
instead of self.values[option] = value in optionChanged I don't get any
errors.
Is it perhaps not safe to keep the reference to the lambda QString
argument?
It shouldn't make any difference.
Phil
--
http://mail.python.org/mailman/listinfo/python-list
Re: Using ascii numbers in regular expression
jorma kala wrote:
Thanks very much for your reply.
What I mean is that I would like to use the ascii number in a regular
expression pattern.
For instance, if I want to substitute the occurrences of character 'a'
for the character 'b' in a string, instead of doing this:
re.subn('a','b','')
I'd like to specify the ascii number of a (which is 97)
I tried converting 97 to hexadecimal (with hex()) and tried this
re.subn(''\0x61,'b','')
but it doesnt work.
I need this because I'm working on non printable characters.
[snip]
You're almost there:
re.subn('\x61','b','')
or better yet:
re.subn(r'\x61','b','')
--
http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
Phil Thompson wrote: On Tue, 28 Apr 2009 11:18:31 +0200, Diez B. Roggisch de...@nospam.web.de wrote: As the documentation of pyqt clearly states, connecting signals doesn't increment the refcount on a passed slot, thus you need to keep a reference to your slots around. But it does increase the refcount for lambda slots. Has that changed? It has been a while, but I've been bitten by this before, so I was pretty sure about my answer. Support for lambda slots was add in PyQt v4.1.1 (released December 2006). Unfortunately after I had the chance to play with PyQt for the last time. Thanks for clarifying! Diez -- http://mail.python.org/mailman/listinfo/python-list
Query related to matplotlib
I would like to draw a chart which takes 'dates' in x axes and some values in y axes. I would like to draw a simple chart using matplotlib. Can someone tell me which submodule i could use for this purpose? The module has to support in the way that i can draw more than one set can be passed to Y axes. So it will generate more than one line. Thanks, Srini Now surf faster and smarter ! Check out the new Firefox 3 - Yahoo! Edition http://downloads.yahoo.com/in/firefox/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Help AIX 5.3 build on Python-3.1a2
-On [20090427 20:31], prueba...@latinmail.com (prueba...@latinmail.com) wrote: ./Modules/ld_so_aix xlc_r -q64 -bI:Modules/python.exp build/ temp.aix-5.3-3.1//ptst/Python-3.1a2/Modules/_tkinter.o build/ temp.aix-5.3-3.1//ptst/Python-3.1a2/Modules/tkappinit.o -L/usr/X11R6/ lib64 -L/usr/X11R6/lib -L/usr/local/lib -ltk8.3 -ltcl8.3 -lX11 -o build/lib.aix-5.3-3.1/_tkinter.so ld: 0706-006 Cannot find or open library file: -l tk8.3 ld:open(): A file or directory in the path name does not exist. Well, do you have TK installed? It seems so, but are the paths passed to the compiler/linker correct (-L) for locating libtk8.3.so? -- Jeroen Ruigrok van der Werven asmodai(-at-)in-nomine.org / asmodai イェルーン ラウフロック ヴァン デル ウェルヴェン http://www.in-nomine.org/ | http://www.rangaku.org/ | GPG: 2EAC625B Time is a twofold teacher, harsh and yet patient like no-one... -- http://mail.python.org/mailman/listinfo/python-list
Re: Web based application development using python
On Apr 28, 5:07 pm, Tim Hoffman zutes...@gmail.com wrote: On Apr 28, 7:50 pm, Rahul r.warhe...@gmail.com wrote: On Apr 28, 1:02 pm, Marco Mariani ma...@sferacarta.com wrote: Rahul wrote: 1) Do you have any idea about web based support (like mod_python) provided by python.org (official web site) Details: - As we know mod_python is used for embeding python code into apache server. so, i want to know whether mod_python is officially supported by python.org or if there is other such framework for embeding python on web server Forget about mod_python, everything else is better. This list (the first result upon googling for python web frameworks) is actually up to date, and a good start. http://wiki.python.org/moin/WebFrameworks Just don't ask which one is best for everything, or which one is The Official Standard Way Of Doing Things. but i want to know which is the official standard recommended by python. But there isn't There are a number of frameworks out there each with there own set of strengths and weaknesses, you shoul dbe looking at each ones vibrancy (community), suitablility for your application, etc... T T Thanks tim This information was really of help to me -- http://mail.python.org/mailman/listinfo/python-list
Re: Web framework for embedded system
Thomas Heller theller at python.net writes: I'm looking for a lightweight web-framework for an embedded system. The system is running a realtime linux-variant on a 200 MHz ARM processor, Python reports a performance of around 500 pystones. You can start with webpy (http://webpy.org/) and build up from there. The web application will not be too fancy, no databases involved for example, but it will need to control some simple peripherals (some parallel in/out, some dacs) attached to the system. It should provide a user interface showing the current state and allowing to manipulate it via a browser, and I will probably need to support some rpc as well. Does this sound sensible at all? Any suggestions? I don't know how Python will affect the real-time tasks your system is performing. You may want to look at a web framework in C (e.g. http://www.koanlogic.com/klone/index.html). Regards, Suraj -- http://mail.python.org/mailman/listinfo/python-list
Re: Re: sorted() erraticly fails to sort string numbers
uuid wrote: I am at the same time impressed with the concise answer and disheartened by my inability to see this myself. My heartfelt thanks! Don't be disheartened! Many people -- myself included, absolutely! -- occasionally let a blind spot show in their messages to this list. BTW: container[:] = sorted(container, key=getkey) ... is equivalent to: container.sort(key=getkey) (unless I'm showing *my* blind spot here) -- http://mail.python.org/mailman/listinfo/python-list
How to locate the bit in bits string?
Hi: If I use an integer to represent bits: e.g. 99 represents '1100011' How can I locate, say the second bit of 99(i.e. '1')? Although bin(99)[4] could be used to locate it, this transform cost too much memory (99 only needs 2Bytes, while string '1100011' needs 7Bytes). Anyone knows how to locate the second bit without using bin() function? Thank you very much:D -- Li -- Time is all we have and you may find one day you have less than you think -- http://mail.python.org/mailman/listinfo/python-list
Re: sorted() erraticly fails to sort string numbers
On 2009-04-28 16:18:43 +0200, John Posner jjpos...@snet.net said: Don't be disheartened! Many people -- myself included, absolutely! -- occasionally let a blind spot show in their messages to this list. Thanks for the encouragement :) BTW: container[:] = sorted(container, key=getkey) ... is equivalent to: container.sort(key=getkey) (unless I'm showing *my* blind spot here) I don't think etree element objects support the .sort method. At least in lxml they don't (http://codespeak.net/lxml/api/elementtree.ElementTree.Element-class.html) -- http://mail.python.org/mailman/listinfo/python-list
Re: Best way to evaluate boolean expressions from strings?
Thank you very much, Gabriela and Peter! I'm going for Pyparsing. :) -- Gustavo. -- http://mail.python.org/mailman/listinfo/python-list
Re: How to locate the bit in bits string?
Li Wang wrote: Hi: If I use an integer to represent bits: e.g. 99 represents '1100011' How can I locate, say the second bit of 99(i.e. '1')? Although bin(99)[4] could be used to locate it, this transform cost too much memory (99 only needs 2Bytes, while string '1100011' needs 7Bytes). Anyone knows how to locate the second bit without using bin() function? You mean def get_bit(number, bit): return (number bit) 1 ? -tkc -- http://mail.python.org/mailman/listinfo/python-list
Third Party Modules
Hi Everyone, I know this is most likely a basic question and you will roll your eyes, but I am just starting out with Python (hobbyist) and I see many tutorials on the web referring to the use of external modules. However, when I locate them, they often come as a zipped folder with a number of files. How do I install them? In addition, is there an easy way to manage external modules? Some I see require additional modules not included. Where I am coming from is R, which has a point-and-click way of getting packages not distributed with the version of the software, so that is my point of reference. Many thanks! - Brock -- http://mail.python.org/mailman/listinfo/python-list
What do you think of ShowMeDo
Hi, I've just stumbled over this (http://showmedo.com/) and being the very visual person I am, it seems like it could be a good way to learn about python. However, before I smack down $60, I wondered if anyone had any opinions on it. My gut feel is that it could be pretty good. ALJ -- http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
Phil Thompson p...@riverbankcomputing.com wrote in message
news:mailman.4690.1240925876.11746.python-l...@python.org...
On Tue, 28 Apr 2009 14:54:41 +0200, Denis L n...@spam.com wrote:
Phil Thompson p...@riverbankcomputing.com wrote in message
news:mailman.4664.1240907352.11746.python-l...@python.org...
On Tue, 28 Apr 2009 03:53:34 +0200, Denis L n...@spam.com wrote:
Hello,
I'm experiencing odd errors on both windows and linux with the
following
code:
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class Options(QDialog):
def __init__(self, values):
QDialog.__init__(self)
self.values = values
fooEdit = QLineEdit(values['foo'])
self.connect(fooEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('foo', value))
barEdit = QLineEdit(values['bar'])
self.connect(barEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('bar', value))
layout = QVBoxLayout()
layout.addWidget(fooEdit)
layout.addWidget(barEdit)
self.setLayout(layout)
def optionChanged(self, option, value):
self.values[option] = value
print self.values
def main(args):
app = QApplication(args)
values = dict(foo='', bar='')
dialog = Options(values)
dialog.show()
app.exec_()
if __name__ == '__main__':
main(sys.argv)
If I type a character in fooEdit, another character in barEdit, and
then
delete the character from barEdit I get an unhandled win32 exception
occured
in python.exe on windows and segfault on linux.
If I type a character in fooEdit, delete it, and then type a character
in
barEdit I get:
{'foo': PyQt4.QtCore.QString(u'a'), 'bar': ''}
{'foo': PyQt4.QtCore.QString(u''), 'bar': ''}
{'foo': Traceback (most recent call last):
File L:\home\dev\python\test.py, line 17, in lambda
lambda value: self.optionChanged('bar', value))
File L:\home\dev\python\test.py, line 27, in optionChanged
print self.values
MemoryError
I'm using Python 2.5.4 and PyQt 4.4.3-1
Thanks in advance for any help.
Works fine for me with current versions.
Phil
I have noticed that if I do self.values[option] = QString(value)
instead of self.values[option] = value in optionChanged I don't get any
errors.
Is it perhaps not safe to keep the reference to the lambda QString
argument?
It shouldn't make any difference.
Phil
Last idea, C++ declaration of textChanged signal is this:
void textChanged (const QStringtext)
would self.values[option] = value store the reference to QString? And if so
is that safe, to access that object after my slot returns?
As far as I can see C++ equivalent would be
QString* pointer = text; then derferencing that pointer later in the code.
I can see how this could cause problems.
Btw you are using PyQt 4.4.4 correct? What version of python?
--
http://mail.python.org/mailman/listinfo/python-list
Re: How to locate the bit in bits string?
On 28 Apr, 16:36, Li Wang li.wan...@gmail.com wrote: Hi: If I use an integer to represent bits: e.g. 99 represents '1100011' How can I locate, say the second bit of 99(i.e. '1')? Although bin(99)[4] could be used to locate it, this transform cost too much memory (99 only needs 2Bytes, while string '1100011' needs 7Bytes). Anyone knows how to locate the second bit without using bin() function? Thank you very much:D -- Li -- Time is all we have and you may find one day you have less than you think If we consider 8 bit, a solution may be the follow: a = 99 # bin(a) = 0b1100011 0b1101 a 97 0b1110 a 99 as you view, you set the nth bit to 0, and view if the result is same as 'a'. If is same then the nth bit doesn't set. If you write the above code in a loop, you can test which bit you want. Hi. -- http://mail.python.org/mailman/listinfo/python-list
Re: How to locate the bit in bits string?
2009/4/29 Tim Chase python.l...@tim.thechases.com: Li Wang wrote: Hi: If I use an integer to represent bits: e.g. 99 represents '1100011' How can I locate, say the second bit of 99(i.e. '1')? Although bin(99)[4] could be used to locate it, this transform cost too much memory (99 only needs 2Bytes, while string '1100011' needs 7Bytes). Anyone knows how to locate the second bit without using bin() function? You mean def get_bit(number, bit): return (number bit) 1 ? Hummm, I have tried this method too, the problem is its time complexity. If the length of my bits is n, then the time complexity is O(n). When I tried to implement this in practice, it did consume a lot of time. So do you know how could I locate the bit in O(1) time? Transform it into a string is a method, but takes too much space (when I try to process a 2M file, it used more than 100M memory.). Thank you very much. -tkc -- Li -- Time is all we have and you may find one day you have less than you think -- http://mail.python.org/mailman/listinfo/python-list
Re: Third Party Modules
On 28 Apr, 17:02, Brock btibe...@gmail.com wrote: Hi Everyone, I know this is most likely a basic question and you will roll your eyes, but I am just starting out with Python (hobbyist) and I see many tutorials on the web referring to the use of external modules. However, when I locate them, they often come as a zipped folder with a number of files. How do I install them? In addition, is there an easy way to manage external modules? Some I see require additional modules not included. Where I am coming from is R, which has a point-and-click way of getting packages not distributed with the version of the software, so that is my point of reference. Many thanks! - Brock If you are on Unix-like machine, unzip the archive in a some directory, do cd into the new directory and, from command line, do: python ./setup.py build (verify there is the script setup.py), and then python ./setup.py install (with root's permissions). On Win32 usually there are an automatic installer. Hi. -- http://mail.python.org/mailman/listinfo/python-list
Re: python segfaulting, MemoryError (PyQt)
On Tue, 28 Apr 2009 17:10:51 +0200, Denis L n...@spam.com wrote:
Phil Thompson p...@riverbankcomputing.com wrote in message
news:mailman.4690.1240925876.11746.python-l...@python.org...
On Tue, 28 Apr 2009 14:54:41 +0200, Denis L n...@spam.com wrote:
Phil Thompson p...@riverbankcomputing.com wrote in message
news:mailman.4664.1240907352.11746.python-l...@python.org...
On Tue, 28 Apr 2009 03:53:34 +0200, Denis L n...@spam.com wrote:
Hello,
I'm experiencing odd errors on both windows and linux with the
following
code:
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class Options(QDialog):
def __init__(self, values):
QDialog.__init__(self)
self.values = values
fooEdit = QLineEdit(values['foo'])
self.connect(fooEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('foo', value))
barEdit = QLineEdit(values['bar'])
self.connect(barEdit, SIGNAL('textChanged(QString)'),
lambda value: self.optionChanged('bar', value))
layout = QVBoxLayout()
layout.addWidget(fooEdit)
layout.addWidget(barEdit)
self.setLayout(layout)
def optionChanged(self, option, value):
self.values[option] = value
print self.values
def main(args):
app = QApplication(args)
values = dict(foo='', bar='')
dialog = Options(values)
dialog.show()
app.exec_()
if __name__ == '__main__':
main(sys.argv)
If I type a character in fooEdit, another character in barEdit, and
then
delete the character from barEdit I get an unhandled win32 exception
occured
in python.exe on windows and segfault on linux.
If I type a character in fooEdit, delete it, and then type a
character
in
barEdit I get:
{'foo': PyQt4.QtCore.QString(u'a'), 'bar': ''}
{'foo': PyQt4.QtCore.QString(u''), 'bar': ''}
{'foo': Traceback (most recent call last):
File L:\home\dev\python\test.py, line 17, in lambda
lambda value: self.optionChanged('bar', value))
File L:\home\dev\python\test.py, line 27, in optionChanged
print self.values
MemoryError
I'm using Python 2.5.4 and PyQt 4.4.3-1
Thanks in advance for any help.
Works fine for me with current versions.
Phil
I have noticed that if I do self.values[option] = QString(value)
instead of self.values[option] = value in optionChanged I don't get
any
errors.
Is it perhaps not safe to keep the reference to the lambda QString
argument?
It shouldn't make any difference.
Phil
Last idea, C++ declaration of textChanged signal is this:
void textChanged (const QStringtext)
would self.values[option] = value store the reference to QString? And if
so
is that safe, to access that object after my slot returns?
As far as I can see C++ equivalent would be
QString* pointer = text; then derferencing that pointer later in the
code.
I can see how this could cause problems.
If there was a bug with lambda slots it's been fixed by now.
Btw you are using PyQt 4.4.4 correct? What version of python?
PyQt v4.5 snapshot, Python v2.6.2 and v3.0.1.
Phil
--
http://mail.python.org/mailman/listinfo/python-list
Re: How can I get Tkinter to work in Python? (I tried many things)
On Mon, 27 Apr 2009 17:49:26 -0700 (PDT), tom...@gmail.com wrote: [snip] There are errors, but since there is many of them: here is a cut out of the _tkinter errors: libpython2.6.a(_tkinter.o): In function `Tkapp_CallProc': /home/tomzam/mylib6/Python-2.6.2/./Modules/_tkinter.c:1263: undefined reference to `Tcl_MutexLock' I believe this message means that something named _tkinter.c was previously compiled into an object file named _tkinter.o, which was bundled into a library named libpython2.6.a; and that when you attempt to use libpython2.6.a to satisfy the external references of something (not identified) that you're trying to link, the linker discovers that _tkinter.o contains a function Tkapp_CallProc that (on line 1263 of _tkinter.c) attempts to call function Tcl_MutexLock, but the linker can't find anything named Tcl_MutexLock to satisfy it. Tcl_MutexLock is probably *supposed* to be provided by some Tcl runtime library, but not being very knowledgeable, I don't know what library. Just before the beginning of the list of error messages, you'll probably find the command line that's running the linker, and it probably names a bunch of libraries, one of which is supposed to include Tcl_Mutexlock but doesn't. I apologize for being so vague; with any luck, someone much smarter will come along soon. -- To email me, substitute nowhere-spamcop, invalid-net. -- http://mail.python.org/mailman/listinfo/python-list
Re: Restart generator when it is exhausted.
On Tue, 2009-04-28 at 10:41 +, Duncan Booth wrote:
Lacrima lacrima.ma...@gmail.com wrote:
If it is not possible what are common techniques to use iterator or
generator objects that allow restarting when it is needed?
The usual thing if you want to use the generator's output more than once
would be to convert the generator to a list, then you can iterate over it
as often as you want.
a = ['a', 'b', 'c']
g = (i for i in a)
restartable = list(g)
If you want the output of the generator to potentially change each time you
iterate then you need to create a new generator.
More verbosely, but without putting your generator in , you can use the
iterator protocol to create a reusable iterable:
An iterable is a class with an __iter__ method that returns an iterator.
So for example:
class Iterator(object):
def __init__(self, filename):
self.f = open(filename)
def __iter__(self):
return self
def next(self):
line = self.f.readline()
if not line:
raise StopIteration
return line.strip()[:8]
is an iterator (which is also an iterable), which will grab each line of
a file, returning the first eight non-whitespace characters until the
file is used up. Then the iterator is exhausted, and will continue to
raise StopIteration each time it is called.
class Iterable(object):
def __init__(self, filename):
self.filename = filename
def __iter__(self):
return Iterator(self.filename)
This is a reusable iterable which returns a new instance of the Iterator
class above each time it is exhausted.
So given a file hello.txt:
Hello world
Hola mundo
Guten tag, weld.
The classes can be used as followed:
iterator = Iterator('hello.txt')
for i in xrange(3):
print *** %d *** % i
for j in iterator:
print j
*** 0 ***
Hello wo
Hola mun
Guten ta
*** 1 ***
*** 2 ***
iterable = Iterable('hello.txt')
for i in xrange(3):
print *** %d *** % i
for j in iterable:
print j
*** 0 ***
Hello wo
Hola mun
Guten ta
*** 1 ***
Hello wo
Hola mun
Guten ta
*** 2 ***
Hello wo
Hola mun
Guten ta
When Iterator hits a StopIteration, it passes out of the inner loop, and
when it comes back in, the inner loop calls iterator.__iter__(), and
gets the same exhausted iterator (which immediately breaks the inner
loop by raising StopIteration). In Iterable, when the loop calls
iterable.__iter__(), it gets a fresh iterator, so it can loop over the
file again.
The important thing is that when you call x.__iter__() (which you do
when entering a loop), you get a fresh iterator that won't just call
StopIteration right away.
Cheers,
Cliff
--
http://mail.python.org/mailman/listinfo/python-list
Re: suggestion on a complicated inter-process communication
Thanks a lot for reply. I understand it is abnormal to implement such IPC, while it is worthy for my application. Well, my process3 and 4 are from an outside application, which both need License Check and os.system to involk. From my experience, if Process5 involks Process3, such License Check can be very very slow (even slower than its real run). That is why I need to separate Process3 and 4 onto different processes to proceed. On Apr 28, 1:57 am, Jonathan Gardner jgard...@jonathangardner.net wrote: On Apr 27, 8:59 pm, Way csw...@gmail.com wrote: Hello friends, I have a little messy situation on IPC. Please if you can, give me some suggestion on how to implement. Thanks a lot! - denotes create MainProcess - Process1 - Process3 (from os.system) | - Process2 (from os.system) - Process4 (from os.system) -Process5 I would like to make the communication between Process1 and Process5. Process1 needs Process5's output to provide argument to generate Process3, and in turn Process5 needs to wait Process3 finished. Thank you very much if you can give a hint. Abstraction should resolve this. What I mean is that Process2 shouldn't be defined in terms of what it actually does, but what it appears to do. If you look at each process and think only what its child processes do and what its parent process expects it to do, then your job should get a lot simpler. Process1 expects Process2 to deliver a set of parameters to spawn Process3, and then it will wait until Process3 terminates. Looking at it this way, questions come to mind: Why can't Process2 run Process3 itself? It's unusual to have one process tell another process what to do when it can simply do it itself. By the way, I've never seen a time when this kind of design is necessary. There are other ways around your problem than spawning a bunch of processes. Each process should really be independent of all the other processes, doing only a very well-specified task in a well- specified way. The only time I could think of doing something like this is when you're getting a webserver setup and Process5 needs to communicate with Process3 to render the page or something like that. But even in that case, each process is really independently defined and implemented. -- http://mail.python.org/mailman/listinfo/python-list
Re: What do you think of ShowMeDo
On 28 Apr, 17:09, Astley Le Jasper astley.lejas...@gmail.com wrote: Hi, I've just stumbled over this (http://showmedo.com/) and being the very visual person I am, it seems like it could be a good way to learn about python. However, before I smack down $60, I wondered if anyone had any opinions on it. My gut feel is that it could be pretty good. ALJ It can be useful, but there are many free howtos and tutorial ... and the programming can't be learned with video, but with books! Hi. -- http://mail.python.org/mailman/listinfo/python-list
Re: suggestion on a complicated inter-process communication
Thanks a lot for the reply. I am not familiar with multi-process in Python. I am now using something like: A_prog is an os.system to involk Process3 B_prog is an os.system to involk Process4 --- In Main Process: Process1 = Popen([A_prog], stdin=PIPE, stdout=PIPE) Process2 = Popen([B_prog], stdin=PIPE, stdout=PIPE) cmd = Process2.stdout.readlines() Process1.stdin.write(cmd) if Process1.poll(): Process2.stdin.write(trig from Process1) - In Process5 (another python program): import sys sys.stdout.write(process1 argument) while 1: if sys.stdin.readline().strip() == trig from Process1: break -- However, in this case, Process5's stdout cannot be passed to MainProcess for Process1, since it has not finished (waiting Process. 1/3 finish). I am now using Fifos (an external file) to inter-communicate Process1 and 5. But at first run, it compliants not file found. Is there any possible solution to make it work? Thank you very much! On Apr 28, 1:34 am, Aaron Brady castiro...@gmail.com wrote: On Apr 27, 10:59 pm, Way csw...@gmail.com wrote: Hello friends, I have a little messy situation on IPC. Please if you can, give me some suggestion on how to implement. Thanks a lot! - denotes create MainProcess - Process1 - Process3 (from os.system) | - Process2 (from os.system) - Process4 (from os.system) -Process5 I would like to make the communication between Process1 and Process5. Process1 needs Process5's output to provide argument to generate Process3, and in turn Process5 needs to wait Process3 finished. Thank you very much if you can give a hint. The 'mmap' module can help with getting the data from 5 to 1. It requires creating a file. If it's a small amount of data, any old file will do. You may need a socket in order to wait for Process3 to join, or write a small '.pyd' or '.so' file that gives you access to your system's synchronization object. -- http://mail.python.org/mailman/listinfo/python-list
Re: How to locate the bit in bits string?
On 28 Apr, 17:24, Li Wang li.wan...@gmail.com wrote: 2009/4/29 Tim Chase python.l...@tim.thechases.com: Li Wang wrote: Hi: If I use an integer to represent bits: e.g. 99 represents '1100011' How can I locate, say the second bit of 99(i.e. '1')? Although bin(99)[4] could be used to locate it, this transform cost too much memory (99 only needs 2Bytes, while string '1100011' needs 7Bytes). Anyone knows how to locate the second bit without using bin() function? You mean def get_bit(number, bit): return (number bit) 1 ? Hummm, I have tried this method too, the problem is its time complexity. If the length of my bits is n, then the time complexity is O(n). When I tried to implement this in practice, it did consume a lot of time. So do you know how could I locate the bit in O(1) time? Transform it into a string is a method, but takes too much space (when I try to process a 2M file, it used more than 100M memory.). Thank you very much. -tkc -- Li -- Time is all we have and you may find one day you have less than you think The my solution is good, but the Tim's solution is better, and it is O (1) in time and space. What is you search? I dont'know you general problem, but search the value of a bit in a 2M file ... is strange . Hi. -- http://mail.python.org/mailman/listinfo/python-list
Re: suggestion on a complicated inter-process communication
Way wrote: Hello friends, I have a little messy situation on IPC. Please if you can, give me some suggestion on how to implement. Thanks a lot! - denotes create MainProcess - Process1 - Process3 (from os.system) | - Process2 (from os.system) - Process4 (from os.system) -Process5 I would like to make the communication between Process1 and Process5. Process1 needs Process5's output to provide argument to generate Process3, and in turn Process5 needs to wait Process3 finished. Thank you very much if you can give a hint. -- http://mail.python.org/mailman/listinfo/python-list = My first reaction is to use named pipes. Process1 - P2 - P4 - Process5 NamedPipe (P5 outputs to NamedPipe) Process1 waits for NamedPipe to be made and starts creating Process3 When Process3 is finished it can set an OS level environmental or create a dummy file as a signal to Process5 to finish. P1 becomes orchestrator, NamedPipe is courier, file is smoke signal. This method works when IPC is not a good choice. (Like independent child processes run across the net. A specific file in a specific location effectively creates a specific signal. Whether or not contents are used or even existing is programmer choice.) Hope this helps. Steve -- http://mail.python.org/mailman/listinfo/python-list
Re: Getting the dir from the other ancestor ?
tuxagb wrote: On 28 Apr, 15:01, Stef Mientki stef.mien...@gmail.com wrote: hello, I have a class, derived from some user defined class (User_Defined_Ancestor) and some basic class (Basic_Ancestor). One of the major tasks of the Basic_Ancestor, is to hide all kinds of implementation details for the user, so the user can concentrate on the functional design. One of things I need to know are the methods and attributes of the Basic_Ancestor. Both classes are dynamic, i.e. attributes are added during run time. class Master ( User_Defined_Ancestor, Basic_Ancestor ) : def __init__ ( self, *args, **kwargs ) : Basic_Ancestor.__init__ ( self, *args, **kwargs ) . class Basic_Ancestor ( object ) : def __init__ ( self, ) : self.other = dir ( User_Defined_Ancestor ) def Get_Attributes ( self ) : return dir ( self ) - dir ( self.other ) Now the problem is, I don't know User_Defined_Ancestor in Basic_Ancestor. I can't pass it through the parameter list, because I use *args, **kwargs I possibly could use some global variable, but that's not my preference. Any other suggestions ? thanks, Stef Mientki In anytime, if you do dir() in a class B, that extends a class A, you have all fields of A also. That's exactly the problem I encounter ;-) After some trial and error, I found this solution: class Basic_Ancestor ( object ) : def __init__ ( self, ) : # Collect all methods and attributes of other classes self.Exclude_Dir = [] Base_Classes = self.__class__.__bases__ for BC in Base_Classes : if BC != My_Control_Class : self.Exclude_Dir += dir ( BC ) cheers, Stef -- http://mail.python.org/mailman/listinfo/python-list
Re: suggestion on a complicated inter-process communication
On 28 Apr, 17:40, Way csw...@gmail.com wrote: Thanks a lot for reply. I understand it is abnormal to implement such IPC, while it is worthy for my application. Well, my process3 and 4 are from an outside application, which both need License Check and os.system to involk. Sounds delightful! Anyway, looking at your diagram (edited to fit)... Main | \- P1 - P3 (from os.system) \- P2 (from os.system) - P4 (from os.system) -P5 ...if P1, P2 and P4 are able to propagate input and output, then this is just a matter of having something in the main process which monitors the input from P5 (via P4 and P2) and which relays the input to P3 (via P1). This could be as simple as the following: to_p1.write(from_p2.read()) If this isn't sophisticated enough, because you only want to read some details from P2, you could either try and read a predetermined amount from P2, or you could write a communications handler which monitors the input from P2 using a select.poll object. If the main process is supposed to be doing other things, then it's quite likely that you'll have to do something involving either select.poll or threads, anyway. Paul -- http://mail.python.org/mailman/listinfo/python-list
stuck with PyOBEX
So I installed the module and tryed to make it work but... It gave me: Traceback (most recent call last): File first.py, line 24, in module client2.connect() File C:\Python25\lib\PyOBEX\client.py, line 359, in connect return Client.connect(self, header_list = [headers.Target(uuid)]) File C:\Python25\lib\PyOBEX\client.py, line 119, in connect self.socket = socket.socket(socket.AF_BLUETOOTH, socket.SOCK_STREAM, AttributeError: 'module' object has no attribute 'AF_BLUETOOTH' Exit Code: 1 This module asks the socket module for AF_BLUETOOTH... in the socket module there is no such thing as AF_BLUETOOTH. Could it be that the person that made PyOBEX modified his socket module and forgot to give his socket module? Or am I missing something? Maybe AF_BLUETOOTH stands for something that a programmer would know but I am a beginner so... Is there a OBEX module for Python on windows? -- http://mail.python.org/mailman/listinfo/python-list
Re: Light (general) Inter-Process Mutex/Wait/Notify Synchronization?
Gunter Henriksen wrote: If you don't want to use a 3rd party module you could use the multiprocessing module That is definitely good for when I have a tree of processes which are all Python applications. I use it for that. But I am looking for something where the Python application can interact conveniently with an arbitrary external application. Using a socket/pipe and shared memory is convenient, but not feasible when system call overhead matters. Linux doesn't do interprocess communication very well. The options are pipes (clunky), sockets (not too bad, but excessive overhead), System V IPC (nobody uses that) and shared memory (unsafe). If you want to see IPC right, what you really need is the QNX microkernel, and its messaging system. I've pumped uncompressed video through the QNX messaging system and had only 2% of the CPU devoted to message overhead. The basic primitives are MsgSend, MsgReceive, and MsgReply, which do about what you'd expect and do it very fast. Linux lacks this. If you're using CPython, don't worry about socket overhead. CPython is so slow you'll never notice it. John Nagle -- http://mail.python.org/mailman/listinfo/python-list
Re: How to locate the bit in bits string?
Li Wang wrote:
2009/4/29 Tim Chase python.l...@tim.thechases.com:
Li Wang wrote:
If I use an integer to represent bits:
[snip]
Hummm, I have tried this method too, the problem is its time
complexity. If the length of my bits is n, then the time complexity is
O(n). When I tried to implement this in practice, it did consume a lot
of time.
I'm not sure I follow here -- your original post said that you
have an integer. With an integer, my function is O(1) as you
request. It sounds like you're *not* representing your bits as
an integer. Either that, or it's a gargantuan number (say, more
than 64 bits? Maybe more than 1k bits?) that you want to
bit-slice. In that case, you need to know a bit more about the
storage structure. However, assuming it's a raw bit-stream, you
might be able to do something like this (untested, but should be
fairly close)
data = file('source.bin').read()
def get_bit(source, bit):
idx, bit = divmod(bit, 8)
byte = ord(source[len(source) - (1+idx)])
return (byte bit) 1
print get_bit(data, 3141592) # the 3,141,592nd bit
you might have to tweak for endian'ness.
-tkc
--
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Re: Why bool( object )?
En Tue, 28 Apr 2009 09:22:01 -0300, Colin J. Williams c...@ncf.ca escribió: Lie Ryan wrote: Aaron Brady wrote: This makes it so all objects except False, None, 0, and empty containers are true by default. I am not convinced that 'if a generic object' should have any meaning; it should probably throw an exception. Is it part of Python's look and feel or its mentality? Is it part of the Zen? Certainly other ideal types can't be cast from generic objects, so why booleans? Is it an ineffable component of the author's vision for the language? I think that giving arbitrary syntactic constructs meaning is just space-filler. It's worse than syntactic sugar, it's semantic sugar. Why not assign meanings willy- nilly to other random juxtapositions of tokens? It's part of the design decision. In almost all cases (in any language), a so-called Design Decision is rather random and prone to subjective judgment, just as the decision to make bool(int) returns False only on 0, -1, or for all negative values; whether to make bool(100) and exception or True; or round() rounds down or up or even-odd; or the use of brackets vs. indentation; or whether to treat empty list as True or False. I'm puzzled by the last sentence: bool(0) False bool(-1) True bool(-100) True That's the design decision. bool(-1) *might* have been False, and bool(-100) *might* raise an exception. They behave the way they do because of a conscious decision. To Aaron: Programming language design is not a rational science. Most reasoning about is is at best rationalization of gut feelings, and at worst plain wrong. (GvR in python-ideas: http://groups.google.com/group/python-ideas/msg/ac61f03c32578bae ) -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Re: inside-out range function
Steven D'Aprano wrote: ... I wrote a similar function to do this: def monge_shuffle(deck): if len(deck) % 2: # Odd number of items. deck[:] = deck[0::2] + deck[1::2][::-1] else: # Even number of items. deck[:] = deck[1::2] + deck[0::2][::-1] return deck Oooh, shiny fun!!! How's this for that: def monge_shuffle2(deck): even = (len(deck) ^ 1) 1 return deck[even::2] + deck[-2::-2] --Scott David Daniels scott.dani...@acm.org -- http://mail.python.org/mailman/listinfo/python-list
Re: suggestion on a complicated inter-process communication
On 28 Apr, 17:44, Way csw...@gmail.com wrote: Thanks a lot for the reply. I am not familiar with multi-process in Python. I am now using something like: A_prog is an os.system to involk Process3 B_prog is an os.system to involk Process4 --- In Main Process: Process1 = Popen([A_prog], stdin=PIPE, stdout=PIPE) Process2 = Popen([B_prog], stdin=PIPE, stdout=PIPE) cmd = Process2.stdout.readlines() Careful here: this may want to read until process 2 has closed its stream, which may only occur on exit, normally. Process1.stdin.write(cmd) if Process1.poll(): Process2.stdin.write(trig from Process1) - In Process5 (another python program): import sys sys.stdout.write(process1 argument) Careful here, too: this output may not be sent immediately, due to buffering issues. while 1: if sys.stdin.readline().strip() == trig from Process1: break And this test may not be satisfied, since the main process may still be waiting for output from process 5 (via process 2), not reaching the point where it writes a response. Paul -- http://mail.python.org/mailman/listinfo/python-list
Re: stuck with PyOBEX
alejandro wrote: So I installed the module and tryed to make it work but... It gave me: Traceback (most recent call last): File first.py, line 24, in module client2.connect() File C:\Python25\lib\PyOBEX\client.py, line 359, in connect return Client.connect(self, header_list = [headers.Target(uuid)]) File C:\Python25\lib\PyOBEX\client.py, line 119, in connect self.socket = socket.socket(socket.AF_BLUETOOTH, socket.SOCK_STREAM, AttributeError: 'module' object has no attribute 'AF_BLUETOOTH' Exit Code: 1 This module asks the socket module for AF_BLUETOOTH... in the socket module there is no such thing as AF_BLUETOOTH. Could it be that the person that made PyOBEX modified his socket module and forgot to give his socket module? Or am I missing something? Maybe AF_BLUETOOTH stands for something that a programmer would know but I am a beginner so... Is there a OBEX module for Python on windows? AF_BLUETOOTH seems to be specific to *nix-systems. At least under debian and ubuntu, I've got it defined. So it seems it is not supported under windows - you should consider the author if that's a mistake, or by design. Diez -- http://mail.python.org/mailman/listinfo/python-list
