ANN: encutils 0.9
what is it -- Encoding detection collection for Python developed mainly for use in cssutils but may be useful standalone too. about this release -- 0.9 is a bugfix release. license --- encutils has a dual-license, please choose whatever you prefer: * encutils is published under the LGPL 3 or later * encutils is published under the Creative Commons License download For download options see http://cthedot.de/encutils/ encutils probably needs Python 2.4 or higher (tested with Python 2.6.2, 2.5.2 and 2.4.4 on Vista only) Bug reports, comments, etc are very much appreciated! Thanks. Christof -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
PyAMF 0.4.2 released
The PyAMF team is proud to announce the release of 0.4.2! PyAMF [1] is a lightweight library that allows Flash and Python applications to communicate via Adobes ActionScript Message Format. This is a bugfix release [2], see the changelog [3] for the complete list of changes. A brief overview of the changes: - Support for decoding the 'source' property on ArrayCollections - Fixed an issue in the GAE adapter where dynamic properties would be missing on referenced objects - Fixed a critical issue with AMF0 reference counting when encoding remoting responses - Support for Django i18n ugettext_lazy - Added support for microseconds for datetime objects - Support for property types on SQLAlchemy mapped classes - Support for property types for Google AppEngine db.Model and db.Expando Check out the download page [4], installation instructions [5] or the API documentation [6] for more information. Questions? First stop is the mailing list [7] but we also hang out on IRC [8]. Cheers, the PyAMF team. [1] http://pyamf.org [2] http://pyamf.org/milestone/0.4.2 [3] http://pyamf.org/browser/pyamf/tags/release-0.4.2/CHANGES.txt [4] http://pyamf.org/wiki/Download [5] http://pyamf.org/wiki/Install [6] http://api.pyamf.org [7] http://pyamf.org/wiki/MailingList [8] irc://irc.collab.eu/pyamf -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
Python-URL! - weekly Python news and links (Apr 24)
QOTW: ... [C]alling Python Object-Orientated is a bit of an insult :-). I would say that Python is Ego-Orientated, it allows me to do what I want. - Martin P. Hellwig April 25: Python Bug Day A perfect opportunity to get involved in Python development, bring your own issues to attention, discuss them and (hopefully) resolve them together with the core developers. http://mail.python.org/pipermail/python-announce-list/2009-April/007401.html Surprising behavior of `and` with lists: http://groups.google.com/group/comp.lang.python/t/69f0ff9adbdbbfbe/ Best way to compare two binary files: http://groups.google.com/group/comp.lang.python/t/70b4ad0605287c28/ Determine if two lists contains the same elements (with duplicates): http://groups.google.com/group/comp.lang.python/t/3ecc64c918ff776e/ How to transparently add modules to an installed package (without modifying it): http://groups.google.com/group/comp.lang.python/t/435bdf86030acc20/ What's a good strategy to write Python code aimed at being rewritten in C later? http://groups.google.com/group/comp.lang.python/t/7affed04edcf521c/ python.exe not found - how to fix PATH issues on Windows: http://groups.google.com/group/comp.lang.python/t/421756cc7875c8b0/ Python, Basic, nostalgia, and goto considered harmful (long thread): http://groups.google.com/group/comp.lang.python/t/ce6900e499334046/ How to represent table joins in a non-relational database (e.g. BigTable in Google App Engine) http://groups.google.com/group/comp.lang.python/t/786770da42168af3/ A mathematical puzzle: express numbers as sum of squares http://groups.google.com/group/comp.lang.python/t/358bc4893cffc0f4/ This time, the man bites the python: http://groups.google.com/group/comp.lang.python/t/b2ff4307aca821d5/ Everything Python-related you want is probably one or two clicks away in these pages: Python.org's Python Language Website is the traditional center of Pythonia http://www.python.org Notice especially the master FAQ http://www.python.org/doc/FAQ.html PythonWare complements the digest you're reading with the marvelous daily python url http://www.pythonware.com/daily Just beginning with Python? This page is a great place to start: http://wiki.python.org/moin/BeginnersGuide/Programmers The Python Papers aims to publish the efforts of Python enthusiats: http://pythonpapers.org/ The Python Magazine is a technical monthly devoted to Python: http://pythonmagazine.com Readers have recommended the Planet sites: http://planetpython.org http://planet.python.org comp.lang.python.announce announces new Python software. Be sure to scan this newsgroup weekly. http://groups.google.com/group/comp.lang.python.announce/topics Python411 indexes podcasts ... to help people learn Python ... Updates appear more-than-weekly: http://www.awaretek.com/python/index.html The Python Package Index catalogues packages. http://www.python.org/pypi/ The somewhat older Vaults of Parnassus ambitiously collects references to all sorts of Python resources. http://www.vex.net/~x/parnassus/ Much of Python's real work takes place on Special-Interest Group mailing lists http://www.python.org/sigs/ Python Success Stories--from air-traffic control to on-line match-making--can inspire you or decision-makers to whom you're subject with a vision of what the language makes practical. http://www.pythonology.com/success The Python Software Foundation (PSF) has replaced the Python Consortium as an independent nexus of activity. It has official responsibility for Python's development and maintenance. http://www.python.org/psf/ Among the ways you can support PSF is with a donation. http://www.python.org/psf/donations/ The Summary of Python Tracker Issues is an automatically generated report summarizing new bugs, closed ones, and patch submissions. http://search.gmane.org/?author=status%40bugs.python.orggroup=gmane.comp.python.develsort=date Although unmaintained since 2002, the Cetus collection of Python hyperlinks retains a few gems. http://www.cetus-links.org/oo_python.html Python FAQTS http://python.faqts.com/ The Cookbook is a collaborative effort to capture useful and interesting recipes. http://code.activestate.com/recipes/langs/python/ Many Python conferences around the world are in preparation. Watch this space for links to them. Among several Python-oriented RSS/RDF feeds available, see: http://www.python.org/channews.rdf
itools 0.60.1 released
itools is a Python library, it groups a number of packages into a single meta-package for easier development and deployment: itools.abnf itools.i18n itools.stl itools.core itools.ical itools.tmx itools.csv itools.odf itools.uri itools.datatypesitools.pdf itools.vfs itools.gettext itools.pkg itools.web itools.git itools.relaxng itools.workflow itools.handlers itools.rest itools.xapian itools.html itools.rss itools.xliff itools.http itools.srx itools.xml Now Python 2.6 is required. New feature in itools.git, there are now facilities to start a process that will specialize in calling Git commands, and send the data back to the parent process. This is useful for applications that may take more than a little memory, so instead of forking a big process we fork an small process; this reduces the probability of a MemoryError, and saves the time to copy large chunks of memory. (This is a work-around to the fact that Git is not yet available as a library, but the mechanism could be useful for anything that uses the 'subprocess' module.) The itools.handlers package now includes a read-only version of the Git database, it is named 'ROGitDatabase'. Some errors fixed, including #640. Resources - Download http://download.hforge.org/itools/0.60/itools-0.60.1.tar.gz Home http://www.hforge.org/itools/ Mailing list http://www.hforge.org/community/ http://archives.hforge.org/index.cgi?list=itools Bug Tracker http://bugs.hforge.org/ -- J. David Ibáñez Itaapy http://www.itaapy.com Tel +33 (0)1 42 23 67 45 9 rue Darwin, 75018 Paris Fax +33 (0)1 53 28 27 88 -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
Re: Strange problem when using imp.load_module
Well spotted :) That does seem to be the problem. Adding removal of the .pyc file will make the tests pass. I guess that python doesn't use the higher resolution timestamp you can get from at least Solaris when doing 'stat' on a file. Thanks for the help. /Mattias On Apr 23, 10:28 pm, Arnaud Delobelle arno...@googlemail.com wrote: My guess is that without the sleep(1), the imp.load_source function will use the compiled file 'my_module.pyc' created in test_1 instead of compiling the new 'my_module.py' file. HTH -- Arnaud -- http://mail.python.org/mailman/listinfo/python-list
Re: can't find the right simplification
Stef Mientki wrote: hello, I've a program where you can connect snippets of code (which I call a Brick) together to create a program. To make it easier to create these code snippets, I need some simplifications. For simple parameters ( integer, tupple, list etc) this works ok, and is done like this: class _Simple_Par ( object ) : Class to make it more easy to set a Bricks.Par from a control. So instead of : self.Brick.Par [ self.EP[0] ] = Some_Value you can write self.P[0] = Some_Value def __init__ ( self, control ) : self.Control = control def __setitem__ ( self, index, value ) : i = self.Control.EP [ index ] if i : self.Control.Brick.Par [ i ] = value Now I want a similar simplification for the case that Par is a dictionary: So instead of writing: self.Brick.Par [ self.EP[0] ] [ 'Filename' ] = Some_Value I would like to write: self.P[0] [ 'Filename' ] = Some_Value But I can't figure out how to accomplish that ? Any suggestions ? thanks, Stef Mientki Do this work? class _Simple_Par (object): def __init__(self, control): ## class P(object): def __init__(self, parent): self.parent = parent def __getitem__(self, key): return self.parent.Brick.Par[self.parent.EP[key]] self.P = P(self) ## self.Control = control btw, it seems your code violated many of PEP 8 style recommendations. -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
Esmail: oh, I forgot to mention that each list may contain duplicates. Comparing the sorted lists is a possible O(n ln n) solution: a.sort() b.sort() a == b Another solution is to use frequency dicts, O(n): from itertools import defaultdict d1 = defaultdict(int) for el in a: d1[el] += 1 d2 = defaultdict(int) for el in b: d2[el] += 1 d1 == d2 As the arrays (Python lists) become large the second solution may become faster. Bye, bearophile -- http://mail.python.org/mailman/listinfo/python-list
Re: relation class
On Apr 22, 11:34 pm, Aaron Brady castiro...@gmail.com wrote:
On Apr 22, 11:52 am, Aaron Brady castiro...@gmail.com wrote:
On Apr 22, 12:09 am, Chris Rebert c...@rebertia.com wrote:
On Tue, Apr 21, 2009 at 5:51 PM, Aaron Brady castiro...@gmail.com wrote:
Hi all,
I think Python should have a relation class in the standard library.
Fat chance.
Perhaps I'm not understanding relation correctly, but are you not
aware ofhttp://docs.python.org/library/sqlite3.html?
Cheers,
Chris
--
I have a blog:http://blog.rebertia.com
snip
It only supports numbers and strings.
snip
My point is that in undirected relations, it's redundant to maintain
reciprocal membership.
snip
Here is another sample:
Tree= Relation( ( parent, child, direction ) )
nodes= [ object( ) for _ in range( 10 ) ]
Tree( ( nodes[ 0 ], nodes[ 1 ], left ) )
Tree( ( nodes[ 0 ], nodes[ 2 ], right ) )
snip
'select' would need the context
of its caller, which isn't available.
snip
Or, pass 'locals()'. Actually, I discovered an interesting catch to
'locals()'. When you don't use a variable that's in an outer scope in
a function, it doesn't appear in 'locals()'. However, if you just use
it in a blank statement, it magically appears.
def f( ):
... x= []
... def g( ):
... print( locals( ) )
... g( )
...
f( )
{}
def f( ):
... x= []
... def g( ):
... x # empty use of 'x'
... print( locals( ) )
... g( )
...
f( ) # changes the contents of 'locals()'
{'x': []}
Here is what the docs have to say about *that*:
Free variables are returned by locals() when it is called in a
function block.
Since 'x' doesn't appear in the function, 'g' in this case, it isn't
included in 'g's free variables. 'eval' actually therefore doesn't
return exactly the result of evaluating a string where it's used.
def f( ):
... x= []
... def g( ):
... print( eval( 'x' ) )
... g( )
...
f( )
Traceback (most recent call last):
File stdin, line 1, in module
File stdin, line 5, in f
File stdin, line 4, in g
File string, line 1, in module
NameError: name 'x' is not defined
The 'eval' function docs do assert otherwise though:
...the expression is executed in the environment where eval() is
called.
'eval' doesn't obviously keep its contract as shown.
I think some kind of markers would have to replace any identifiers it
would use:
recordset= Tree.select( [ child ],
parent is %var and direction=='left', nodes[0] )
snip
The 'sqlite3' module just uses a question mark. Despite the fact that
variables are separated from exactly where they are used, it has the
advantage, as S. D'Aprano pointed out nearby, of being able to use
queries independently of them, as well as of being legal Python.
If anyone is still reading, there is a further nifty-cool construct
that the 'Relation' class can offer. Given the earlier definition of
'Tree' as an instance of 'Relation', a new class can combine property
descriptors with the select statement.
class TreeNode:
relation= Tree
left= Relation.getter(
child, parent is ? and direction=='left' )
nodes= [ TreeNode( ) for _ in range( 10 ) ]
record= nodes[ 0 ].left
Getting the 'left' member of an instance of this class is just
syntactic sugar for a long-hand query. It only returns one field of
an arbitrary element of the recordset. It only allows one '?' in the
definition, since getter functions only take one argument: self!
Here's the definition of 'getter':
@staticmethod
def getter( field, where ):
def _getter( self ):
return getattr( next(
self.relation.select( '*', where, self ) ), field )
return property( fget= _getter )
It could be an attribute of the module, not specifically of the
Relation class... which might even be advisable. You could even
combine the 'relation' member into the call to 'getter', so 'getter'
wouldn't have to retrieve it as 'self.relation'. That has the
disadvantage of increasing repetition of the relation in the class
statement, but enables a class to participate in multiple relations.
Come to think of it, you could write it as 'Tree.getter', and
compromise. Then 'getter' becomes:
def getter( self, field, where ):
def _getter( ob ):
return getattr( next(
self.select( '*', where, ob ) ), field )
return property( fget= _getter )
and 'TreeNode' becomes:
class TreeNode:
left= Tree.getter(
child, parent is ? and direction=='left' )
You might want 'getter', 'getiter', and 'getone' methods, which return
a set of, an iterator over, and just the field of an arbitrary one of
the matching records respectively.
Proof-of-concept isn't even complete; but nonetheless, pretty cool,
eh?
--
http://mail.python.org/mailman/listinfo/python-list
Re: and [True,True] -- [True, True]?????
Steven D'Aprano wrote: On Mon, 20 Apr 2009 15:13:15 -0500, Grant Edwards wrote: I fail to see the difference between length greater than 0 and list is not empty. They are, by definition, the same thing, aren't they? For built-in lists, but not necessarily for arbitrary list-like sequences. I think a list-like sequence that does not emulate this behavior (False when empty, True otherwise) should be considered a buggy implementation of the list interface. -- http://mail.python.org/mailman/listinfo/python-list
Re: Presentation software for Python code
alex23 wrote: How do you feel about reStructuredText? If you're open to it, I highly recommend Bruce: http://pypi.python.org/pypi/bruce That looks like it would be perfect. Unfortunately it doesn't seem to work on my Windows laptop: C:\Documents and Settings\Michael\Desktop\bruce-3.2.1C:\Python25\python.exe bru ce.pyw ..\bruce-3.2.1-examples\test_bullet_mode.rst Traceback (most recent call last): File bruce.pyw, line 6, in module run.main() File bruce-library.zip\bruce\run.py, line 25, in main File bruce-library.zip\bruce\run.py, line 217, in cmd_line File bruce-library.zip\bruce\run.py, line 313, in run File bruce-library.zip\bruce\presentation.py, line 31, in start_presentation File bruce-library.zip\bruce\page.py, line 29, in create File bruce-library.zip\bruce\layout.py, line 143, in create File bruce-library.zip\pyglet\graphics\__init__.py, line 348, in add File bruce-library.zip\pyglet\graphics\__init__.py, line 436, in _get_domain File bruce-library.zip\pyglet\graphics\vertexdomain.py, line 135, in create_ domain File bruce-library.zip\pyglet\graphics\vertexdomain.py, line 174, in __init_ _ File bruce-library.zip\pyglet\graphics\vertexbuffer.py, line 117, in create_ mappable_buffer File bruce-library.zip\pyglet\graphics\vertexbuffer.py, line 383, in __init_ _ File bruce-library.zip\pyglet\graphics\vertexbuffer.py, line 301, in __init_ _ File bruce-library.zip\pyglet\gl\lib_wgl.py, line 94, in __call__ File bruce-library.zip\pyglet\gl\lib.py, line 63, in MissingFunction pyglet.gl.lib.MissingFunctionException: glGenBuffers is not exported by the avai lable OpenGL driver. VERSION_1_5 is required for this functionality. Exception exceptions.AttributeError: 'VertexDomain' object has no attribute 'at tributes' in bound method VertexDomain.__del__ of vertexdom...@a9c7350 allocs =[] ignored I don't understand this. OpenGL Extensions Viewer says I have OpenGL 1.5 and the glGenBuffers function. -- http://mail.python.org/mailman/listinfo/python-list
Re: and [True,True] -- [True, True]?????
Gerhard Häring wrote: len() make it clear that the argument is a sequence. Not necessarily. Classes that overrides __len__ may fool that assumption (well, in python classes that overrides special functions may do anything it is never intended to do). I often think an if item: as is item workable?. What the exact definition of workable is just something I don't care, at least until I need to debug the code. A container is workable if it contains something; most of the time, an empty sequence does not have any value (pun intended) and thus unworkable. -- http://mail.python.org/mailman/listinfo/python-list
Re: Presentation software for Python code
On Apr 24, 4:23 pm, Michael Hoffman 4g4trz...@sneakemail.com wrote: That looks like it would be perfect. Unfortunately it doesn't seem to work on my Windows laptop: I don't understand this. OpenGL Extensions Viewer says I have OpenGL 1.5 and the glGenBuffers function. That's a shame, if you feel like pursuing it you should report the error to the pyglet devs, but I'd certainly understand if you didn't. -- http://mail.python.org/mailman/listinfo/python-list
Re: What is the best framework or module in Python for a small GUI based application development?
On Apr 22, 9:11 am, srinivasan srinivas sri_anna...@yahoo.co.in wrote: Hi, Could you suggest me some modules in Python which can be used to develop GUI based applications? and tell me which could be the best(in terms of efficiency) one for a small GUI based application development? Thanks, Srini Bollywood news, movie reviews, film trailers and more! Go tohttp://in.movies.yahoo.com/ For browser-based stuff--that is, web apps--as far as I know the only options for Python-based web app GUI is Pyjamas, a python-to- javascript compiler and a web widget set, which would allow the GUI to be written in Python but then it translates it to javascript: http://code.google.com/p/pyjamas/ And then you could use one of the aforementioned Python web frameworks. -- http://mail.python.org/mailman/listinfo/python-list
Re: Large data arrays?
Hi John, John Machin sjmac...@lexicon.net writes: The Morton layout wastes space if the matrix is not square. Your 100K x 4K is very non-square. Looks like you might want to use e.g. 25 Morton arrays, each 4K x 4K. What I found was that Morton layout shall be usable, if the shape is rectangular and both dimensions are powers of two. But, all examples were done with equal dimensions, so I am a bit confused here. From my access pattern, it would be probably better to combine 25 rows into one slice and have one matrix where every cell contains 25 rows. Are there any objections about that? Best regards Ole -- http://mail.python.org/mailman/listinfo/python-list
Re: sorting two corresponding lists?
On Apr 24, 2:32 am, Hans DushanthaKumar hans.dushanthaku...@hcn.com.au wrote: Just being pedantic here :) [items[x] for x in [i for i in map(values.index, new_values)]] Is the same as [items[x] for x in map(values.index, new_values)] It's also the same as [items[x] for x in [values.index(i) for i in new_values]] Which reduces to [items[values.index(i)] for i in new_values] (Although 'i' is not a good choice of variable as it represents a value, not an index) Anyway it doesn't work well if the 'values' list has repeated values, e.g. items = ['spam', 'eggs', 'wafer'] values = [3, 7, 3] -- Arnaud -- http://mail.python.org/mailman/listinfo/python-list
Re: Large data arrays?
Hi Nick, Nick Craig-Wood n...@craig-wood.com writes: I'd start by writing a function which took (x, y) in array co-ordinates and transformed that into (z) remapped in the Morton layout. This removes the possibility to use the sum() and similar methods of numpy. Implementing them myself is probably much worse than using Numpys own. Alternatively you could install a 64bit OS on your machine and use my scheme! Well: I am just the developer. Ofcourse I could just raise the requirements to use my software, but I think it is good style to keep them as low as possible. Best regards Ole -- http://mail.python.org/mailman/listinfo/python-list
Re: Regular expression to capture model numbers
John Machin sjmac...@lexicon.net (JM) wrote: JM On Apr 24, 1:29 am, Piet van Oostrum p...@cs.uu.nl wrote: obj = re.compile(r'(?:[a-z]+[-0-9]|[0-9]+[-a-z]|-+[0-9a-z])[-0-9a-z]*', re.I) JM Understandable and maintainable, I don't think. Suppose that instead JM the first character is limited to being alphabetic. You have to go JM through the whole process of elaborating the possibilites again, and I JM don't consider that process qualifies as express[ing] complicated JM conditions like that. No, I don't think regular expressions are the best tool for these kind of tests. I just wanted to show that it *could* be done. By the way, your additional hypothetical requirement that the first character should be alphabetic just makes it easier: only the first alternative remains. But on the other hand, suppose you would have the requirement that the pattern should not end in a hyphen then it becomes even uglier. Or when there should never be two hyphens in a row, I wouldn't even think of using a re, although theoretically it would be possible. Translating these requirements into re's is not `composable'. -- Piet van Oostrum p...@cs.uu.nl URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4] Private email: p...@vanoostrum.org -- http://mail.python.org/mailman/listinfo/python-list
Re: What IDE support python 3.0.1 ?
Sam (I presume),
Like you I am also in the process of learning to program in Python. I
have been using Python 2.5.2 for quite some time but recently made the
switch to 3.0.1. Why? Because I read an article where Guido van Rossum
himself recommended that anyone starting out learning Python now was
wasting their time if they didn't start with Python 3. Some folks on
this list will tell you there is not much difference and that seems to
be true but I pleased that I made the switch.
Now for your question about an IDE. I am presuming you are just
beginning, perhaps done some programming in another language and
probably using a Windows based PC. Given that there are some things I
would recommend you stay away from (this will get the juices going :-)
): Vi, Vim, Emacs and all those old fashioned UNIX/Linux based editors -
they are just too hard and why bother anyway, there are much more
civilised ways of proving your manhood. Eclipse is also an over-kill. I
would recommend any of the popular text editors; most will recognise
Python files.
I can tell you what I use:
*EditPad+* - http://www.editplus.com/index.html - A great general
purpose text editor that has the additional benefit of clip libraries
(what?). This might not seem important but it is a great time saver. A
clip library is a text file of code snippets that when you
'double-click' the required clip the editor inserts that code at the
current cursor position. For example the following is a clip I use for
the heading of a short script file:
#T=Short script
^# ^!.py
^# The purpose of this script is
def main():
{code here}
main()
After the clip has been inserted the cursor is positioned where the ^!
string is (before .py) waiting for the script name to be inserted. You
just build these clips to suit yourself. TextPad is another text editor
with the same features.
The main drawback with EditPlus is that when you run a Python script
from within EditPlus and that script uses stdin (eg. an input()
function) the editor can't handle it and you get an error message. I
overcome this problem by using easygui (http://easygui.sourceforge.net/)
dialogs for text input; a piece of cake :-) . Another drawback is that
EditPlus is shareware and you have to pay for it (US35).
*SciTE* - http://www.scintilla.org/SciTE.html - Scite is a very good
little editor, it does not have the bells and whistles that editors
like EditPlus have but it does recognise Python files and can run them
from within the editor. It can also handle stdin (not that elegantly,
but it works) so you don't need the easygui work-around and its free.
*IDLE* - the built-in Python IDE. I have it configured so that the
editor panel loads first rather than the Python prompt. Everything runs
in IDLE!
*PyScripter* - http://code.google.com/p/pyscripter/ - From the web site:
PyScripter is a free and open-source Python Integrated Development
Environment (IDE) created with the ambition to become competitive in
functionality with commercial Windows-based IDEs available for other
languages. This is a true IDE with most of the things you would expect.
However, I find that it gets a bit buggy at times. It does support
Python 3 and is free so its worth a try.
There are several other good Python editor/IDE's but they require
wxPython and it has not yet been made available in a Python 3 compatible
version.
I hope that helps. Give me a reply if you want any more help with any of
these things. Easygui is something that is really worth getting to know.
A copy of Python (Second Edition) by Toby Donaldson (ISBN 13:
978-0-321-58544-8) is another good thing to have when you are learning.
Regards,
Peter
--
*Peter Anderson*
There is nothing more difficult to take in hand, more perilous to
conduct, or more uncertain in its success, than to take the lead in the
introduction of a new order of things—Niccolo Machiavelli, /The Prince/,
ch. 6
--
http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
John Yeung gallium.arsen...@gmail.com (JY) wrote: JY It takes care of the duplicates, but so does your initial solution, JY which I like best: sorted(a)==sorted(b) JY This is concise, clear, and in my opinion, the most Pythonic. It may JY well even be the fastest. (If you didn't have to match up the numbers JY of duplicates, the set solution would be most Pythonic and probably JY fastest.) But it may fail if the list cannot be sorted because it contains incomparable elements: a = [1, 2, 3+4j] b = [2, 3+4j, 1] set(a) == set(b) True sorted(a)==sorted(b) Traceback (most recent call last): File stdin, line 1, in module TypeError: no ordering relation is defined for complex numbers In Python 3 there are even more incomparable objects pairs. -- Piet van Oostrum p...@cs.uu.nl URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4] Private email: p...@vanoostrum.org -- http://mail.python.org/mailman/listinfo/python-list
Re: getter and setter and list appends
dasacc22 dasac...@gmail.com (d) wrote: d Ah thank you for clarifying, I did confuse instance and class d attributes from creating the list in the class def. I actually just d spiffed up that class to represent a portion of a much larger class d that needs getter and setter for children. Doing as you said fixed my d problem, heres the code as reference for w/e d class Widget(object): d _children = None d _parent = None You still have them as class variables here. Now they are only used as defaults because you assign to them in the instances so the instance variables will be created then. But I think it is still confusing to have these class variables here that you never use as such. Maybe this is some leftover from Java experience where you do declare instance variables at the class level? d def __init__(self, parent=None): d self.children = [] d self.parent = parent d @property d def children(self): d return self._children d @children.setter d def children(self, obj): d self._children = obj What is the added value of using a property for the children attribute? Why not just use an instance variable directly? Also a Java inheritance? -- Piet van Oostrum p...@cs.uu.nl URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4] Private email: p...@vanoostrum.org -- http://mail.python.org/mailman/listinfo/python-list
Re: Why can function definitions only use identifiers, and not attribute references or any other primaries?
Scott David Daniels wrote: I am afraid it will make it too easy to define functions in other modules remotely, a tempting sharp stick to poke your eye out with. It's not very hard at the moment, and I don't see lots of eyes flying by. I don't know about Ruby where monkeypatching seems to be common practice, though. Imagine debugging a pile of code that includes a module with: import random def random.random(): return .42 No need to imagine. I can do the same, one line shorter: import random random.random = lambda: .42 -- http://mail.python.org/mailman/listinfo/python-list
Re: and [True,True] -- [True, True]?????
On Fri, 24 Apr 2009 06:50:01 +, Lie Ryan wrote: Gerhard Häring wrote: len() make it clear that the argument is a sequence. Not necessarily. len() works on dicts and sets, and they're not sequences. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
On Thu, 23 Apr 2009 21:51:42 -0400, Esmail wrote: set(a) == set(b)# test if a and b have the same elements # check that each list has the same number of each element # i.e. [1,2,1,2] == [1,1,2,2], but [1,2,2,2] != [1,1,1,2] for elem in set(a): a.count(elem) == b.count(elem) Ah .. this part would take care of different number of duplicates in the lists. Cool. At significant cost of extra work. Counting the number of times a single element occurs in the list is O(N). Counting the number of times every element occurs in the list is O(N**2). Sorting is O(N*log N), so for large lists, sorting will probably be much cheaper. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: Why can function definitions only use identifiers, and not attribute references or any other primaries?
On Thu, 23 Apr 2009 10:48:57 -0700, Scott David Daniels wrote: I am afraid it will make it too easy to define functions in other modules remotely, a tempting sharp stick to poke your eye out with. It's not terribly difficult to do so already: def spam(): ... return spam spam spam ... import math math.spam = spam math.spam() 'spam spam spam' Note also, that it will not be so easy to find the definition of a function provided as a argument to a failing function. Right now you can get the function name and (with a bit more effort) its module. Imagine debugging a pile of code that includes a module with: import random def random.random(): return .42 Easy-peasy. import random random.random = lambda: 0.42 random.random() 0.41998 random.random.__name__ 'lambda' random.random.__module__ '__main__' Sure, if somebody wants to really work at it, they could create a function that looks exactly like the original, including claiming to come from the same module, but that's possible now anyway. I don't think the proposed syntax is useful because it doesn't actually gain us anything. Currently, you add a function to a class at class creation time: class Spam(object): def spam(self): return spam spam spam Adding functions to a class after the class already exists is rare, but not unheard of. Currently you can do this: def ham(self): return ham is not spam Spam.ham = ham del ham # if you can be bothered And you're done. The proposal gives us this: class Spam(object): pass # Need to have a class before you can add methods to it. def Spam.spam(self): return spam spam spam def Spam.ham(self): return ham is not spam Whatever benefit there might be from doing this, it's so minor I don't think it's worth the effort to implement it. Unlike decorators, I'd be surprised if it opens the door to bigger and better things. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: and [True,True] -- [True, True]?????
On Thu, 23 Apr 2009 17:18:25 +0800, Leo wrote: There's also the performance issue. I might have a sequence-like structure where calling len() takes O(N**2) time, (say, a graph) but calling __nozero__ might be O(1). Why defeat the class designer's optimizations? Is that true? Calling len() actually traverses the whole list? Not for built-in lists, but for sequences created by somebody else, who knows what it does? -- Steven -- http://mail.python.org/mailman/listinfo/python-list
wxpython notebook oddness
Can anyone tell me why these two behave differfently? http://pastebin.com/m57bee079 vs http://pastebin.com/m3c044b29 Lawson -- http://mail.python.org/mailman/listinfo/python-list
Raw command line arguments
How to pass the raw command line arguments to the python?
Such as:
mypython.py txt -c Test Only {Help}
The arguments I hope to get is:
txt -c Test Only {Help} -- Keep the
quotation marks in the arguments.
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Re: unicode(lString, utf8) vs. lString.encode(utf8) vs. urjakiś tekst
Sorry, my mistake. My interntion was post this message on pl.comp.lang.python. Jax -- http://mail.python.org/mailman/listinfo/python-list
Re: Raw command line arguments
On Fri, Apr 24, 2009 at 2:40 AM, Enchanter ensoul.magaz...@gmail.com wrote:
How to pass the raw command line arguments to the python?
Such as:
mypython.py txt -c Test Only {Help}
The arguments I hope to get is:
txt -c Test Only {Help} -- Keep the
quotation marks in the arguments.
Remember that the quotes are parsed by the shell before python ever
receives the arguments, so you have to deal with it in whatever is
calling python.
Recall/note the differences between:
rm foo bar #delete foo and delete bar
rm foo bar #delete one file with a space in its name but no quotes in its name
rm 'foobarbaz' #delete one file with double-quotes in its name
rm foo\bar\baz #delete the same file as in the previous example
Therefore, you need to invoke the script differently to take account
of the shell's quote processing by adding another set of quotes, like
so:
mypython.py txt -c 'Test Only' {Help}
#or alternatively:
mypython.py txt -c \Test Only\ {Help}
Cheers,
Chris
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http://blog.rebertia.com
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Convert numpy.ndarray into normal array
Hi group, I'm confused, kind of. The application I'm writing currently reads data from a FITS file and should display it on a gtk window. So far I have: [...] pb = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8, width, height) pb_pixels = pb.get_pixels_array() print(type(fits_pixels)) print(type(pb_pixels)) which gives type 'numpy.ndarray' type 'array' So now I want to copy the fits_pixels - pb_pixels. Doing pb_pixels = fits_pixels works and is insanely fast, however the picture looks all screwed-up (looks like a RGB picture of unititialized memory, huge chunks of 0s interleaved with lots of white noise). Doing the loop: for x in range(width): for y in range(height): pb_pixels[y, x] = fits_pixels[y, x] works as expected, but is horribly slow (around 3 seconds for a 640x480 picture). So now I've been trying to somehow convert the array in a fast manner, but just couldn't do it. What exactly is array anyways? I know array.array, but that's something completely different, right? Does anyone have hints on how to go do this? Kind regards, Johannes -- Meine Gegenklage gegen dich lautet dann auf bewusste Verlogenheit, verlästerung von Gott, Bibel und mir und bewusster Blasphemie. -- Prophet und Visionär Hans Joss aka HJP in de.sci.physik 48d8bf1d$0$7510$54022...@news.sunrise.ch -- http://mail.python.org/mailman/listinfo/python-list
if statement, with function inside it: if (t = Test()) == True:
Hello, I'm trying to do a if statement with a function inside it. I want to use that variable inside that if loop , without defining it. def Test(): return 'Vla' I searching something like this: if (t = Test()) == 'Vla': print t # Vla or if (t = Test()): print t # Vla -- The long way t = Test() if (t == 'Vla': print t # must contain Vla Greetings, GCMartijn -- http://mail.python.org/mailman/listinfo/python-list
Re: if statement, with function inside it: if (t = Test()) == True:
On Fri, 24 Apr 2009 03:00:26 -0700, GC-Martijn wrote: Hello, I'm trying to do a if statement with a function inside it. I want to use that variable inside that if loop , without defining it. def Test(): return 'Vla' I searching something like this: if (t = Test()) == 'Vla': print t # Vla or if (t = Test()): print t # Vla Fortunately, there is no way of doing that with Python. This is one source of hard-to-debug bugs that Python doesn't have. -- The long way t = Test() if (t == 'Vla': print t # must contain Vla What's wrong with that? -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: if statement, with function inside it: if (t = Test()) == True:
On Fri, Apr 24, 2009 at 3:00 AM, GC-Martijn gcmart...@gmail.com wrote: Hello, I'm trying to do a if statement with a function inside it. I want to use that variable inside that if loop , without defining it. def Test(): return 'Vla' I searching something like this: if (t = Test()) == 'Vla': print t # Vla or if (t = Test()): print t # Vla -- The long way t = Test() if (t == 'Vla': print t # must contain Vla Disregarding some ugly hacks, Python does not permit assignment in expressions, so what you're asking for is not possible. For the goods of readability, prevention of errors, and simplicity, Python forces you to do it the long way (the Right Way(tm) if you ask most Python partisans). If you could explain your situation and the context of your question in greater detail, someone might be able to suggest an alternate structure for your code which obviates your desire for such a construct. Cheers, Chris -- I have a blog: http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: if statement, with function inside it: if (t = Test()) == True:
On 24 apr, 12:11, Steven D'Aprano st...@remove-this- cybersource.com.au wrote: On Fri, 24 Apr 2009 03:00:26 -0700, GC-Martijn wrote: Hello, I'm trying to do a if statement with a function inside it. I want to use that variable inside that if loop , without defining it. def Test(): return 'Vla' I searching something like this: if (t = Test()) == 'Vla': print t # Vla or if (t = Test()): print t # Vla Fortunately, there is no way of doing that with Python. This is one source of hard-to-debug bugs that Python doesn't have. -- The long way t = Test() if (t == 'Vla': print t # must contain Vla What's wrong with that? -- Steven- Tekst uit oorspronkelijk bericht niet weergeven - - Tekst uit oorspronkelijk bericht weergeven - Nothing is wrong with it , but it cost more lines (= more scrolling) When possible I want to keep my code small. -- http://mail.python.org/mailman/listinfo/python-list
Re: and [True,True] -- [True, True]?????
Steven D'Aprano st...@remove-this-cybersource.com.au writes: len() works on dicts and sets, and they're not sequences. Of course dicts and sets are sequences. But there are also sequences on which len doesn't work. You could use: sum(1 for x in seq) Of course iterating through seq may have undesired side effects. -- http://mail.python.org/mailman/listinfo/python-list
Re: if statement, with function inside it: if (t = Test()) == True:
Chris Rebert c...@rebertia.com writes: Python forces you to do it the long way (the Right Way(tm) if you ask most Python partisans). If you could explain your situation and the context of your question in greater detail, someone might be able to suggest an alternate structure for your code which obviates your desire for such a construct. One very common situation is matching something against a series of regexps, and ugly hacks often end up being more attractive than the long way. If you want to do it the pointy headed way, start with the article http://www.valuedlessons.com/2008/01/monads-in-python-with-nice-syntax.html -- http://mail.python.org/mailman/listinfo/python-list
Re: Raw command line arguments
Enchanter wrote:
How to pass the raw command line arguments to the python?
Such as:
mypython.py txt -c Test Only {Help}
The arguments I hope to get is:
txt -c Test Only {Help} -- Keep the
quotation marks in the arguments.
As Chris has said, the shell (and the C runtime) preprocesses the line
before python ever sees it. However, if you're on Windows, there is a
function GetCommandLine, located in Kernel32.dll, which I *think* keeps
the raw bytes typed by the user. Clearly, that would be a non-portable
answer, but here's some samples if you want to try it:
import sys
print sys.argv#this one loses the quotes
import ctypes
#print ctypes.windll.kernel32.GetModuleHandleA
#hdl = ctypes.windll.kernel32.GetModuleHandleA(0)
#print hdl
func = ctypes.windll.kernel32.GetCommandLineA
print func
func.restype = ctypes.c_char_p
cmd = ctypes.windll.kernel32.GetCommandLineA()
print cmd #this one gives a single string, such as the one below:
C:\ProgFiles\Python26\python.exe
M:\Programming\Python\sources\dummy\args.py txt -c Test Only (Help)
If you do go this route, but still want to be portable, you could make
this code conditional on platform, then document the user to use
escaping on Linux and Apple, while you do this approach for Windows.
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PDB break
Hi, I need to track where a certain condition is met in a program. Checking on pdb docs I find the break statement : b(reak) [[/filename/:]/lineno/ | /function/[, /condition/]] But it requires me to name a line/function where my condition is tested. Now there are far too many places in a project where this condition may be set to true, and I might overlook some (and it would take an awful lot of time to identify them all). Is there a statement that allows me to stop execution when a condition is met regardless of where this happens? Thx. Ricardo. -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
John Yeung wrote: so does your initial solution, which I like best: sorted(a)==sorted(b) This is concise, clear, and in my opinion, the most Pythonic. It may well even be the fastest. Great .. I can live with that :-) -- http://mail.python.org/mailman/listinfo/python-list
Re: and [True,True] -- [True, True]?????
Paul Rubin wrote:
Steven D'Aprano st...@remove-this-cybersource.com.au writes:
len() works on dicts and sets, and they're not sequences.
Of course dicts and sets are sequences. But there are also sequences
on which len doesn't work.
That was my intuition, too. But Python takes a different stance:
from collections import *
for obj in [(), [], {}, set()]:
... print((%r: % (obj,)) + , .join(a.__name__ for a in [Iterable,
Container, Sequence] if isinstance(obj, a)))
...
(): Iterable, Container, Sequence
[]: Iterable, Container, Sequence
{}: Iterable, Container
set(): Iterable, Container
Peter
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Re: and [True,True] -- [True, True]?????
On Fri, 24 Apr 2009 03:22:50 -0700, Paul Rubin wrote:
Steven D'Aprano st...@remove-this-cybersource.com.au writes:
len() works on dicts and sets, and they're not sequences.
Of course dicts and sets are sequences.
Dicts and sets are explicitly described as other containers:
http://docs.python.org/library/stdtypes.html#sequence-types-str-unicode-
list-tuple-buffer-xrange
Note that addition is included in the table of sequence operations, but
neither dicts nor sets support it:
{} + {}
Traceback (most recent call last):
File stdin, line 1, in module
TypeError: unsupported operand type(s) for +: 'dict' and 'dict'
Nor do they support slicing.
But there are also sequences on which len doesn't work.
You could use: sum(1 for x in seq)
Of course iterating through seq may have undesired side effects.
It's also not guaranteed to terminate.
Well, technically no user-defined function is guaranteed to terminate,
but you know what I mean :)
--
Steven
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Re: best way to compare contents of 2 lists?
MRAB wrote: You could use Raymond Hettinger's Counter class: http://code.activestate.com/recipes/576611/ on both lists and compare them for equality. thanks for the pointer, I'll study the code provided. Esmail -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
Arnaud Delobelle: Thanks to the power of negative numbers, you only need one dict: d = defaultdict(int) for x in a: d[x] += 1 for x in b: d[x] -= 1 # a and b are equal if d[x]==0 for all x in d: not any(d.itervalues()) Very nice, I'll keep this for future use. Someday I'll have to study this new new kind of numbers that can represent borrowed items too. Bye, bearophile -- http://mail.python.org/mailman/listinfo/python-list
HTTP Authentication using urllib2
I am trying to authenticate using urllib2. The basic authentication
works if I hard code authheaders.
def is_follows(follower, following):
theurl = 'http://twitter.com/friendships/exists.json?
user_a='+follower+'user_b='+following
username = 'uname1'
password = 'pwd1'
handle = urllib2.Request(theurl)
authheader = Basic %s % base64.encodestring('%s:%s' %
(username, password))
handle.add_header(Authorization, authheader)
try:
return simplejson.load(urllib2.urlopen(handle))
except IOError, e:
print Something wrong. This shouldnt happen
I am trying to refactor this code into how urllib2 expects to do. But
I am getting an error.
def is_follows(follower, following):
url = 'http://twitter.com/friendships/exists.json?user_a=%suser_b=
%s' %(
follower, following)
#Authenticate once for all
auth_handler = urllib2.HTTPBasicAuthHandler()
auth_handler.add_password(realm='',
uri='http://twitter.com',
user='scorpion032',
passwd='123456')
opener = urllib2.build_opener(auth_handler)
urllib2.install_opener(opener)
try:
return simplejson.load(urllib2.urlopen(url))
except:
print Something wrong. This shouldnt happen
return False
Can U please point what I am missing. As I understand, the Auth
Headers are put appropriately in either cases, but the latter one
doesnt work.
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Re: Convert numpy.ndarray into normal array
Johannes Bauer wrote: Hi group, I'm confused, kind of. The application I'm writing currently reads data from a FITS file and should display it on a gtk window. So far I have: [...] pb = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8, width, height) pb_pixels = pb.get_pixels_array() print(type(fits_pixels)) print(type(pb_pixels)) which gives type 'numpy.ndarray' type 'array' So now I want to copy the fits_pixels - pb_pixels. Doing pb_pixels = fits_pixels This simply makes pb_pixels refer to the same object as fits_pixels. It doesn't copy the values into the existing pb_pixels object. works and is insanely fast, however the picture looks all screwed-up (looks like a RGB picture of unititialized memory, huge chunks of 0s interleaved with lots of white noise). Doing the loop: for x in range(width): for y in range(height): pb_pixels[y, x] = fits_pixels[y, x] works as expected, but is horribly slow (around 3 seconds for a 640x480 picture). This does copy the values into the existing pb_pixels object. So now I've been trying to somehow convert the array in a fast manner, but just couldn't do it. What exactly is array anyways? I know array.array, but that's something completely different, right? Does anyone have hints on how to go do this? You should be able to copy the values using array slicing, something like: pb_pixels[:] = fits_pixels or: pb_pixels[:, :] = fits_pixels perhaps. -- http://mail.python.org/mailman/listinfo/python-list
Re: if statement, with function inside it: if (t = Test()) == True:
Steven D'Aprano wrote: On Fri, 24 Apr 2009 03:00:26 -0700, GC-Martijn wrote: t = Test() if (t == 'Vla': print t # must contain Vla What's wrong with that? It unnecessarily injects the name 't' into the scope. Uli -- Sator Laser GmbH Geschäftsführer: Thorsten Föcking, Amtsgericht Hamburg HR B62 932 -- http://mail.python.org/mailman/listinfo/python-list
Re: if statement, with function inside it: if (t = Test()) == True:
GC-Martijn wrote: On 24 apr, 12:15, Chris Rebert c...@rebertia.com wrote: On Fri, Apr 24, 2009 at 3:00 AM, GC-Martijn gcmart...@gmail.com wrote: Hello, I'm trying to do a if statement with a function inside it. I want to use that variable inside that if loop , without defining it. def Test(): return 'Vla' I searching something like this: if (t = Test()) == 'Vla': print t # Vla or if (t = Test()): print t # Vla -- The long way t = Test() if (t == 'Vla': print t # must contain Vla Disregarding some ugly hacks, Python does not permit assignment in expressions, so what you're asking for is not possible. For the goods of readability, prevention of errors, and simplicity, Python forces you to do it the long way (the Right Way(tm) if you ask most Python partisans). If you could explain your situation and the context of your question in greater detail, someone might be able to suggest an alternate structure for your code which obviates your desire for such a construct. Oke, thanks. I will use the (correct) long way. It's possible in C, but sometimes you might write '=' where you intended '=='. It happens. I've done it myself. :-( Sometimes it's an annoying restriction, but it does reduce bugs. -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
On Apr 24, 7:12 am, bearophileh...@lycos.com wrote: [...] Another solution is to use frequency dicts, O(n): from itertools import defaultdict d1 = defaultdict(int) for el in a: d1[el] += 1 d2 = defaultdict(int) for el in b: d2[el] += 1 d1 == d2 Thanks to the power of negative numbers, you only need one dict: d = defaultdict(int) for x in a: d[x] += 1 for x in b: d[x] -= 1 # a and b are equal if d[x]==0 for all x in d: not any(d.itervalues()) -- Arnaud -- http://mail.python.org/mailman/listinfo/python-list
Re: if statement, with function inside it: if (t = Test()) == True:
On 24 apr, 12:15, Chris Rebert c...@rebertia.com wrote: On Fri, Apr 24, 2009 at 3:00 AM, GC-Martijn gcmart...@gmail.com wrote: Hello, I'm trying to do a if statement with a function inside it. I want to use that variable inside that if loop , without defining it. def Test(): return 'Vla' I searching something like this: if (t = Test()) == 'Vla': print t # Vla or if (t = Test()): print t # Vla -- The long way t = Test() if (t == 'Vla': print t # must contain Vla Disregarding some ugly hacks, Python does not permit assignment in expressions, so what you're asking for is not possible. For the goods of readability, prevention of errors, and simplicity, Python forces you to do it the long way (the Right Way(tm) if you ask most Python partisans). If you could explain your situation and the context of your question in greater detail, someone might be able to suggest an alternate structure for your code which obviates your desire for such a construct. Cheers, Chris -- I have a blog:http://blog.rebertia.com- Tekst uit oorspronkelijk bericht niet weergeven - - Tekst uit oorspronkelijk bericht weergeven - Oke, thanks. I will use the (correct) long way. -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
Thanks all, after reading all the posting and suggestions for alternatives, I think I'll be going with sorted(a)==sorted(b) it seems fast, intuitive and clean and can deal with duplicates too. Best, Esmail -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
Piet van Oostrum wrote: John Yeung gallium.arsen...@gmail.com (JY) wrote: JY It takes care of the duplicates, but so does your initial solution, JY which I like best: sorted(a)==sorted(b) JY This is concise, clear, and in my opinion, the most Pythonic. It may JY well even be the fastest. (If you didn't have to match up the numbers JY of duplicates, the set solution would be most Pythonic and probably JY fastest.) But it may fail if the list cannot be sorted because it contains incomparable elements: Ah .. good point .. something I had not considered. Lucky for me in this case it's not an issue, but something I'll keep in mind for the future. -- http://mail.python.org/mailman/listinfo/python-list
unicode(lString, utf8) vs. lString.encode(utf8) vs. urjakiś tekst
Witam
Zakładam, że kod Pythona w drugiej lini ma:
# -*- coding: utf-8 -*-
oraz gdzieś na początku:
reload(sys)
sys.setdefaultencoding('utf8')
No i mam takie pytania odnośnie unicode w utf8:
Czy obie poniższe linie dają ten sam efekt, czyli obiekt unicode zakodowany w
utf8?
lString = unicode(lString, utf8)
lString = lString.encode(utf8)
Konkretnie chodzi mi czy aby mieć obiekt unicode zakodowany w utf8 muszę robić
coś takiego:
lString = unicode(lString.decode(ISO-8859-15).encode(utf8), utf8)
czy może wystarczy:
lString = lString.decode(ISO-8859-15).encode(utf8)
Dodatkowo mam pytanie: Czy aby mieć ze stringu podanego w kodzie pythona obiekt
unicode zakodowany w utf8 zawsze muszę robić:
lString = unicode(jakiś tekst, utf8)
czy może wystarczy
lString = urjakiś tekst
Pytam, bo ciągłe klepanie unicode(xxx, utf8) jest męczące.
z góry dzięki
Jax
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Re: Presentation software for Python code
Michael Hoffman – Donnerstag, 23. April 2009 19:52 I'm willing to consider TeX- and HTML-based approaches. I can recommend latex with the beamer package. It doesn't directly support formatting of code snippets, but the pygments syntax highlighter comes with a Latex formatter. -- Freedom is always the freedom of dissenters. (Rosa Luxemburg) -- http://mail.python.org/mailman/listinfo/python-list
Re: JSON and Firefox sessionstore.js
Unless I'm badly mistaken, the Firefox sessionstore.js file is supposed to be JSON. ... If it matters, I'm using Firefox 2.0.0.5 under Linux. maybe it can be parsed with PyYAML? -- дамјан ( http://softver.org.mk/damjan/ ) Well when _I_ was in school, I had to run Netscape on HP/UX, displayed on my local X Server running on a Windows 3.1 box. Displayed over a 2400 baud modem. Uphill. Both ways. In the rain. With NOBODY to hold my hands. Because the life of the geek is a lonely life. - aclarke on /. -- http://mail.python.org/mailman/listinfo/python-list
Re: Numpy Performance
Thanks for your replies. @Peter - My arrays are not sparse at all, but I'll take a quick look as scipy. I also should have mentioned that my numpy arrays are of Object type as each data point (row) has one or more text labels for categorization. @Robert - Thanks for the comments about how numpy was optimized for bulk transactions. Most of the processing I'm doing is with individual elements. Essentially, I'm testing tens of thousands of scenarios on a relatively small number of test cases. Each scenario requires all elements of each test case to be scored, then summarized, then sorted and grouped with some top scores captured for reporting. It seems like I can either work toward a procedure that features indexed categorization so that my arrays are of integer type and a design that will allow each scenario to be handled in bulk numpy fashion, or expand RectangularArray with custom data handling methods. Any other recommended approaches to working with tabular data in Python? Cheers, Tim -- http://mail.python.org/mailman/listinfo/python-list
Python-URL! - weekly Python news and links (Apr 24)
QOTW: ... [C]alling Python Object-Orientated is a bit of an insult :-). I would say that Python is Ego-Orientated, it allows me to do what I want. - Martin P. Hellwig April 25: Python Bug Day A perfect opportunity to get involved in Python development, bring your own issues to attention, discuss them and (hopefully) resolve them together with the core developers. http://mail.python.org/pipermail/python-announce-list/2009-April/007401.html Surprising behavior of `and` with lists: http://groups.google.com/group/comp.lang.python/t/69f0ff9adbdbbfbe/ Best way to compare two binary files: http://groups.google.com/group/comp.lang.python/t/70b4ad0605287c28/ Determine if two lists contains the same elements (with duplicates): http://groups.google.com/group/comp.lang.python/t/3ecc64c918ff776e/ How to transparently add modules to an installed package (without modifying it): http://groups.google.com/group/comp.lang.python/t/435bdf86030acc20/ What's a good strategy to write Python code aimed at being rewritten in C later? http://groups.google.com/group/comp.lang.python/t/7affed04edcf521c/ python.exe not found - how to fix PATH issues on Windows: http://groups.google.com/group/comp.lang.python/t/421756cc7875c8b0/ Python, Basic, nostalgia, and goto considered harmful (long thread): http://groups.google.com/group/comp.lang.python/t/ce6900e499334046/ How to represent table joins in a non-relational database (e.g. BigTable in Google App Engine) http://groups.google.com/group/comp.lang.python/t/786770da42168af3/ A mathematical puzzle: express numbers as sum of squares http://groups.google.com/group/comp.lang.python/t/358bc4893cffc0f4/ This time, the man bites the python: http://groups.google.com/group/comp.lang.python/t/b2ff4307aca821d5/ Everything Python-related you want is probably one or two clicks away in these pages: Python.org's Python Language Website is the traditional center of Pythonia http://www.python.org Notice especially the master FAQ http://www.python.org/doc/FAQ.html PythonWare complements the digest you're reading with the marvelous daily python url http://www.pythonware.com/daily Just beginning with Python? This page is a great place to start: http://wiki.python.org/moin/BeginnersGuide/Programmers The Python Papers aims to publish the efforts of Python enthusiats: http://pythonpapers.org/ The Python Magazine is a technical monthly devoted to Python: http://pythonmagazine.com Readers have recommended the Planet sites: http://planetpython.org http://planet.python.org comp.lang.python.announce announces new Python software. Be sure to scan this newsgroup weekly. http://groups.google.com/group/comp.lang.python.announce/topics Python411 indexes podcasts ... to help people learn Python ... Updates appear more-than-weekly: http://www.awaretek.com/python/index.html The Python Package Index catalogues packages. http://www.python.org/pypi/ The somewhat older Vaults of Parnassus ambitiously collects references to all sorts of Python resources. http://www.vex.net/~x/parnassus/ Much of Python's real work takes place on Special-Interest Group mailing lists http://www.python.org/sigs/ Python Success Stories--from air-traffic control to on-line match-making--can inspire you or decision-makers to whom you're subject with a vision of what the language makes practical. http://www.pythonology.com/success The Python Software Foundation (PSF) has replaced the Python Consortium as an independent nexus of activity. It has official responsibility for Python's development and maintenance. http://www.python.org/psf/ Among the ways you can support PSF is with a donation. http://www.python.org/psf/donations/ The Summary of Python Tracker Issues is an automatically generated report summarizing new bugs, closed ones, and patch submissions. http://search.gmane.org/?author=status%40bugs.python.orggroup=gmane.comp.python.develsort=date Although unmaintained since 2002, the Cetus collection of Python hyperlinks retains a few gems. http://www.cetus-links.org/oo_python.html Python FAQTS http://python.faqts.com/ The Cookbook is a collaborative effort to capture useful and interesting recipes. http://code.activestate.com/recipes/langs/python/ Many Python conferences around the world are in preparation. Watch this space for links to them. Among several Python-oriented RSS/RDF feeds available, see: http://www.python.org/channews.rdf
Re: if statement, with function inside it: if (t = Test()) == True:
Ulrich Eckhardt wrote: t = Test() if (t == 'Vla': print t # must contain Vla What's wrong with that? It unnecessarily injects the name 't' into the scope. Since there is no concept in Python of a scope local to block statements, I don't understant what you would like to happen instead. -- http://mail.python.org/mailman/listinfo/python-list
Re: if statement, with function inside it: if (t = Test()) == True:
On Apr 24, 5:00 am, GC-Martijn gcmart...@gmail.com wrote: Hello, I'm trying to do a if statement with a function inside it. I want to use that variable inside that if loop , without defining it. def Test(): return 'Vla' I searching something like this: if (t = Test()) == 'Vla': print t # Vla Here is a thread from 3 weeks ago on this very topic, with a couple of proposed solutions. http://groups.google.com/group/comp.lang.python/browse_frm/thread/9f8e79fa28d69905/e934c73ee3c2dbc2?hl=enq= -- Paul -- http://mail.python.org/mailman/listinfo/python-list
Failed to build these modules:_ctypes
Hello all I can't install neither python 2.6.1 nor 2.6.2 because an error during compilation of _ctypes module, I don't need the module but I don't know how to instruct to skip it. The plattform is Suse 11.0 The steps I performed are the following: ./configure --prefix $HOME/app/Python-2.6.2 make The last command from make with its error is the following gcc -pthread -shared build/temp.linux-i686-2.6/home/ps/soft/ Python-2.6.2/Modules/_ctypes/_ctypes.o build/temp.linux-i686-2.6/home/ ps/soft/Python-2.6.2/Modules/_ctypes/callbacks.o build/temp.linux- i686-2.6/home/ps/soft/Python-2.6.2/Modules/_ctypes/callproc.o build/ temp.linux-i686-2.6/home/ps/soft/Python-2.6.2/Modules/_ctypes/ stgdict.o build/temp.linux-i686-2.6/home/ps/soft/Python-2.6.2/Modules/ _ctypes/cfield.o build/temp.linux-i686-2.6/home/ps/soft/Python-2.6.2/ Modules/_ctypes/malloc_closure.o build/temp.linux-i686-2.6/home/ps/ soft/Python-2.6.2/Modules/_ctypes/libffi/src/prep_cif.obuild/ temp.linux-i686-2.6/home/ps/soft/Python-2.6.2/Modules/_ctypes/libffi/ src/x86/ffi.o build/temp.linux-i686-2.6/home/ps/soft/Python-2.6.2/ Modules/_ctypes/libffi/src/x86/sysv.o -L/home/ps/app/Python-2.6.2/lib - L/usr/local/lib -o build/lib.linux-i686-2.6/_ctypes.so *** WARNING: renaming _ctypes since importing it failed: build/ lib.linux-i686-2.6/_ctypes.so: undefined symbol: ffi_prep_cif_machdep Failed to find the necessary bits to build these modules: bsddb185 dl imageop sunaudiodev To find the necessary bits, look in setup.py in detect_modules() for the module's name. Failed to build these modules: _ctypes running build_scripts any idea? Thanks in advance Pablo -- http://mail.python.org/mailman/listinfo/python-list
Re: getter and setter and list appends
On Apr 24, 4:04 am, Piet van Oostrum p...@cs.uu.nl wrote: dasacc22 dasac...@gmail.com (d) wrote: d Ah thank you for clarifying, I did confuse instance and class d attributes from creating the list in the class def. I actually just d spiffed up that class to represent a portion of a much larger class d that needs getter and setter for children. Doing as you said fixed my d problem, heres the code as reference for w/e d class Widget(object): d _children = None d _parent = None You still have them as class variables here. Now they are only used as defaults because you assign to them in the instances so the instance variables will be created then. But I think it is still confusing to have these class variables here that you never use as such. Maybe this is some leftover from Java experience where you do declare instance variables at the class level? d def __init__(self, parent=None): d self.children = [] d self.parent = parent d @property d def children(self): d return self._children d @children.setter d def children(self, obj): d self._children = obj What is the added value of using a property for the children attribute? Why not just use an instance variable directly? Also a Java inheritance? -- Piet van Oostrum p...@cs.uu.nl URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4] Private email: p...@vanoostrum.org Hi, yes, you are right, this is from previous experience, and thank you for bringing this out. It would be better suited to move those class variables to a comment to stay comfortable perhaps or eliminate them altogether. The property method of parent and children actually calls a _set_as_parent() and _set_as_child() method after setting the private variable to pack the object for display purposes so that children can be detached from the parent (becoming its own parent) as a gui event. -- http://mail.python.org/mailman/listinfo/python-list
Re: Convert numpy.ndarray into normal array
MRAB schrieb: type 'numpy.ndarray' type 'array' So now I want to copy the fits_pixels - pb_pixels. Doing pb_pixels = fits_pixels This simply makes pb_pixels refer to the same object as fits_pixels. It doesn't copy the values into the existing pb_pixels object. Oh okay, I was thinking of C++ std::vectorchar which behaves differently :-/ Switching between languages back and forth is not something I'm good in, appearently. You should be able to copy the values using array slicing, something like: pb_pixels[:] = fits_pixels or: pb_pixels[:, :] = fits_pixels OK, I hadn't been familiar with that syntax at all - need to catch up reading on this. However, it doesn't work (altough probably for another reason): Traceback (most recent call last): File ./guiclient.py, line 433, in on_Result self.__updateresult() File ./guiclient.py, line 385, in __updateresult pb_pixels[:, :] = fits_pixels TypeError: Array can not be safely cast to required type I guess Python fears truncation. However I ensure in advance the values won't be truncated. How can I convince Python that it may safely assume that is true? Kind regards, Johannes -- Meine Gegenklage gegen dich lautet dann auf bewusste Verlogenheit, verlästerung von Gott, Bibel und mir und bewusster Blasphemie. -- Prophet und Visionär Hans Joss aka HJP in de.sci.physik 48d8bf1d$0$7510$54022...@news.sunrise.ch -- http://mail.python.org/mailman/listinfo/python-list
Superclass initialization
Hi again, I am trying to initialize a class inherited from numpy.ndarray: from numpy import ndarray class da(ndarray): def __init__(self, mydata): ndarray.__init__(self, 0) self.mydata = mydata When I now call the constructor of da: da(range(100)) I get the message: ValueError: sequence too large; must be smaller than 32 which I do not understand. This message is generated by the constructor of ndarray, but the ndarray constructor (ndarray.__init__()) has only 0 as argument, and calling ndarray(0) directly works perfect. In the manual I found that the constructor of a superclass is not called implicitely, so there should be no other call to ndarray.__init__() the the one in my __init__ method. I am now confused on where does the call to ndarray come from. How do I correct that? Best regards Ole -- http://mail.python.org/mailman/listinfo/python-list
Re: Superclass initialization
On Fri, 24 Apr 2009 16:04:00 +0200, Ole Streicher wrote: I get the message: ValueError: sequence too large; must be smaller than 32 which I do not understand. This message is generated by the constructor of ndarray, but the ndarray constructor (ndarray.__init__()) has only 0 as argument, and calling ndarray(0) directly works perfect. Perhaps you should post the full trace back instead of just the final line. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: Superclass initialization
On Apr 24, 3:04 pm, Ole Streicher ole-usenet-s...@gmx.net wrote: Hi again, I am trying to initialize a class inherited from numpy.ndarray: from numpy import ndarray class da(ndarray): def __init__(self, mydata): ndarray.__init__(self, 0) self.mydata = mydata When I now call the constructor of da: da(range(100)) I get the message: ValueError: sequence too large; must be smaller than 32 which I do not understand. This message is generated by the constructor of ndarray, but the ndarray constructor (ndarray.__init__()) has only 0 as argument, and calling ndarray(0) directly works perfect. In the manual I found that the constructor of a superclass is not called implicitely, so there should be no other call to ndarray.__init__() the the one in my __init__ method. I am now confused on where does the call to ndarray come from. How do I correct that? Best regards Ole numpy.ndarray has a __new__ method (and no __init__). I guess this is the one you should override. Try: class da(ndarray): def __new__(cls, mydata): return ndarray.__new__(cls, 0) def __init__(self, mydata): self.mydata = mydata -- Arnaud -- http://mail.python.org/mailman/listinfo/python-list
Re: mailbox.mbox.add() sets access time as well as modification time
On 2009-04-23, MRAB goo...@mrabarnett.plus.com wrote: tinn...@isbd.co.uk wrote: It seems to me that mailbox.mbox.add() sets the access time of a mbox file as well as the modification time. This is not good for MUAs that detect new mail by looking to see if the access time is before the modification time. Have I done something wrong somewhere or is mailbox.mbox.add() really as broken as it would appear? [snip] The access time is the time it was last accessed, ie read or modified. Usually. The modification time is the time it was last modified. Usually. The access time can never be before the modification time because it must be accessed in order to be modified! Nonsense. You can set atime and mtime to anything you want. SOP for writing to to an mbox formatted mailbox is to preserve the atime (changing only the mtime) so that other programs know that that there is new mail in the mbox. I know mutt works that way, and I believe that the you've got new mail features in some shells work that way. AFAIK, atimemtime has been the standard way to determine when an mbox contains new mail for at least 20 years. Anybody writing to an mbox mailbox has to follow the rules if they expect to interoperate with other mail applications. If mailbox.mbox.add() doesn't preserve the atime when writing to an mbox, then mailbox.mbox.add is broken. http://www.qmail.org/qmail-manual-html/man5/mbox.html -- Grant Edwards grante Yow! I put aside my copy at of BOWLING WORLD and visi.comthink about GUN CONTROL legislation... -- http://mail.python.org/mailman/listinfo/python-list
Re: Superclass initialization
Steven D'Aprano st...@remove-this-cybersource.com.au writes: Perhaps you should post the full trace back instead of just the final line. No Problem, although I dont see the information increase there: In [318]: class da(ndarray): .: def __init__(self, mydata): .: ndarray.__init__(self, 0) .: self.mydata = mydata .: In [319]: da(range(100)) --- ValueErrorTraceback (most recent call last) /m3d/src/python/ipython console in module() ValueError: sequence too large; must be smaller than 32 The same happens if I put the class definition into a file: the traceback does *not* point to a code line in that source file but to the input line. Again, full trace: In [320]: import da In [321]: da.da(range(100)) --- ValueErrorTraceback (most recent call last) /m3d/src/python/ipython console in module() ValueError: sequence too large; must be smaller than 32 (using python instead of ipython also does not give more details). Best regards Ole -- http://mail.python.org/mailman/listinfo/python-list
Re: Superclass initialization
Arnaud Delobelle arno...@googlemail.com writes: numpy.ndarray has a __new__ method (and no __init__). I guess this is the one you should override. Try: What is the difference? best regards Ole -- http://mail.python.org/mailman/listinfo/python-list
Re: Superclass initialization
On Apr 24, 3:46 pm, Ole Streicher ole-usenet-s...@gmx.net wrote: Arnaud Delobelle arno...@googlemail.com writes: numpy.ndarray has a __new__ method (and no __init__). I guess this is the one you should override. Try: What is the difference? best regards Ole Here's an explanation. http://www.python.org/download/releases/2.2.3/descrintro/#__new__ -- Arnaud -- http://mail.python.org/mailman/listinfo/python-list
repost: http web page fetch question
Given the following...
[cdal...@localhost oakland]$ more basic.py
#!/usr/bin/python
import sched
import time
scheduler = sched.scheduler(time.time, time.sleep)
def print_event(name):
print 'EVENT:', time.time(), name
print 'START:', time.time()
scheduler.enter(2, 1, print_event, ('first',))
scheduler.run()
[cdal...@localhost oakland]$ ./basic.py
START: 1240584506.06
EVENT: 1240584508.06 first
[cdal...@localhost oakland]$
How do I modify it so that it runs every hour on the hour.
--
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Re: mailbox.mbox.add() sets access time as well as modification time
Grant Edwards wrote: On 2009-04-23, MRAB goo...@mrabarnett.plus.com wrote: tinn...@isbd.co.uk wrote: It seems to me that mailbox.mbox.add() sets the access time of a mbox file as well as the modification time. This is not good for MUAs that detect new mail by looking to see if the access time is before the modification time. Have I done something wrong somewhere or is mailbox.mbox.add() really as broken as it would appear? [snip] The access time is the time it was last accessed, ie read or modified. Usually. The modification time is the time it was last modified. Usually. The access time can never be before the modification time because it must be accessed in order to be modified! Nonsense. You can set atime and mtime to anything you want. Well, yes, you can always change atime and mtime and make it look like something happened at a different time to when it actually happened... SOP for writing to to an mbox formatted mailbox is to preserve the atime (changing only the mtime) so that other programs know that that there is new mail in the mbox. I know mutt works that way, and I believe that the you've got new mail features in some shells work that way. AFAIK, atimemtime has been the standard way to determine when an mbox contains new mail for at least 20 years. So atime is used to indicate when it was last read, not last accessed? Hmm... Anybody writing to an mbox mailbox has to follow the rules if they expect to interoperate with other mail applications. If mailbox.mbox.add() doesn't preserve the atime when writing to an mbox, then mailbox.mbox.add is broken. http://www.qmail.org/qmail-manual-html/man5/mbox.html -- http://mail.python.org/mailman/listinfo/python-list
Re: Failed to build these modules:_ctypes
PS schrieb: Hello all I can't install neither python 2.6.1 nor 2.6.2 because an error during compilation of _ctypes module, I don't need the module but I don't know how to instruct to skip it. You only get a warning, right? So a subsequent 'make install' should work. -- http://mail.python.org/mailman/listinfo/python-list
Re: Large data arrays?
On Apr 24, 5:17 pm, Ole Streicher ole-usenet-s...@gmx.net wrote: Hi John, John Machin sjmac...@lexicon.net writes: The Morton layout wastes space if the matrix is not square. Your 100K x 4K is very non-square. Looks like you might want to use e.g. 25 Morton arrays, each 4K x 4K. What I found was that Morton layout shall be usable, if the shape is rectangular and both dimensions are powers of two. But, all examples were done with equal dimensions, so I am a bit confused here. Yes, you are right, it can be done in one hit with a rectangular array. How it is done: in your case you have a 2**17 x 2**12 array, so the Morton index corresponding to (i, j) would have the top 5 bits of i followed by the remaining 12 bits of i interleaved with the 12 bits of j -- scarcely distinguishable from my original suggestion of 25 4Kx4K arrays, once you've ignored the trailing approx 2**17 - 100 elements that you don't need to allocate space for ;-) From my access pattern, it would be probably better to combine 25 rows into one slice and have one matrix where every cell contains 25 rows. Are there any objections about that? Can't object, because I'm not sure what you mean ... how many elements in a cell? Cheers, John -- http://mail.python.org/mailman/listinfo/python-list
Re: Help with code! Gamepad?
On Apr 23, 4:03 pm, Mike Driscoll kyoso...@gmail.com wrote: On Apr 23, 6:46 am, DC16 luster...@gmail.com wrote: I am using pygame and OpenGL. How do I make a gamepad able to move the camera to a side of a cube on screen. Here is the code for keyboard use: import pygame from pygame.locals import * import sys from OpenGLLibrary import * pygame.init() Screen = (800,600) Window = glLibWindow(Screen,caption=Camera Test) View3D = glLibView3D((0,0,Screen[0],Screen[1]),45) View3D.set_view() Camera = glLibCamera([0,0.5,6],[0,0,0]) glLibColorMaterial(True) drawing = 0 Objects = [glLibObjCube(),glLibObjTeapot(),glLibObjSphere (64),glLibObjCylinder(0.5,1.0,64),glLibObjCone(0.5,1.8,64)] while True: key = pygame.key.get_pressed() for event in pygame.event.get(): if event.type == QUIT: pygame.quit() sys.exit() if event.type == KEYDOWN: if event.key == K_ESCAPE: pygame.quit() sys.exit() if event.key == K_RETURN: drawing += 1 if drawing == 5: drawing = 0 if event.key == K_1: glLibColor((255,255,255)) if event.key == K_2: glLibColor((255,0,0)) if event.key == K_3: glLibColor((255,128,0)) if event.key == K_4: glLibColor((255,255,0)) if event.key == K_5: glLibColor((0,255,0)) if event.key == K_6: glLibColor((0,0,255)) if event.key == K_7: glLibColor((128,0,255)) if key[K_LEFT]: Camera.set_target_pos([-6,0.5,0]) elif key[K_RIGHT]: Camera.set_target_pos([6,0.5,0]) elif key[K_UP]: Camera.set_target_pos([0,6,2]) elif key[K_DOWN]: Camera.set_target_pos([0,-6,2]) else: Camera.set_target_pos([0,0.5,6]) Camera.update() Window.clear() Camera.set_camera() Objects[drawing].draw() Window.flip() How do I change it so that a gampad can move the camera in the same way. (Ignore the colour changing code) Thanks, Dexter (DC16) BTW the code was originally by someone else. Try cross-posting to the pygame guys:http://www.pygame.org/wiki/info I read that pyglet will have some sort of gamepad support soon too, so you might want to check that project out as well. - Mike- Hide quoted text - - Show quoted text - I cannot find any code for gamepad/joypad on there. -- http://mail.python.org/mailman/listinfo/python-list
Re: Large data arrays?
Hi John, John Machin sjmac...@lexicon.net writes: From my access pattern, it would be probably better to combine 25 rows into one slice and have one matrix where every cell contains 25 rows. Are there any objections about that? Can't object, because I'm not sure what you mean ... how many elements in a cell? Well, a matrix consists of cells? A 10x10 matrix has 100 cells. Regards Ole -- http://mail.python.org/mailman/listinfo/python-list
python list handling and Lisp list handling
This page says that Python lists are often flexible arrays http://www.brpreiss.com/books/opus7/html/page82.html but also says that their representation is implementation dependent. As far as I see this should mean that element access in Python should run in constant time. Now if so this is a boon, because generally 'A list is a sequence of elements, but it is not a single primitive object; it is made of cons cells, one cell per element. Finding the nth element requires looking through n cons cells, so elements farther from the beginning of the list take longer to access. But it is possible to add elements to the list, or remove elements.' (from http://www.chemie.fu-berlin.de/chemnet/use/info/elisp/elisp_7.html) But are Python lists also indistinguishable from conventional Lisplists for list processing. For example, can I modify a Python list non-destructively? Are they equivalent to Lisp lists. Can CAR and CDR in Lisp be thought of as def car (x): return x[0] def cdr (x): return x[1:] The idea of a list in which elements can be accessed in constant time is novel to me. Mark -- http://mail.python.org/mailman/listinfo/python-list
Re: Large data arrays?
On Apr 25, 1:14 am, Ole Streicher ole-usenet-s...@gmx.net wrote: Hi John, John Machin sjmac...@lexicon.net writes: From my access pattern, it would be probably better to combine 25 rows into one slice and have one matrix where every cell contains 25 rows. Are there any objections about that? Can't object, because I'm not sure what you mean ... how many elements in a cell? Well, a matrix consists of cells? A 10x10 matrix has 100 cells. Yes yes but you said every cell contains 25 rows ... what's in a cell? 25 rows, with each row containing what? -- http://mail.python.org/mailman/listinfo/python-list
Re: gethostbyname blocking
On Apr 23, 2:16 pm, Piet van Oostrum p...@cs.uu.nl wrote: marc wyburn marc.wyb...@googlemail.com (MW) wrote: MW Hi, I am writing anasynchronousping app to check if 1000s of hosts MW are alive very quickly. Everything works extremely quickly unless the MW host name doesn't have a DNS record. MW when calling socket.gethostbynameif there is no record for the host MW the result seems to block all other threads. As an example I have 6 MW threads running and if I pass the class below a Queue with about 30 MW valid addresses with one invalid address in the middle the thread that MW the exception occurs in seems to block the others. What you could do is have two Queues, one with host names, and one with results fromgethostbyname. And an additional thread which gets from the first queue, callsgethostbynameand puts the results in the second queue. The ping threads then should get from the second queue. The lookup thread could even do caching of the results if you often have to repeat the pings for thew same host. -- Piet van Oostrum p...@cs.uu.nl URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4] Private email: p...@vanoostrum.org Hi, I did try this but the socket blocked for so long that this was a real bottleneck. It also seemed that whilst the DNS lookup thread was blocking the other threads were also blocked. I guess this may have something to do with the GIL but I'm still fairly new to threading. I ended up using DNSPython which flys along. I have a thread creating the ping packets and pinging them and another performing a select and logging + filtering any ICMP replies. I may put the DNS code into another thread but the whole script runs faster than I need it to as it is, I've got time.sleeps in the ping thread as I'm scared of saturating the local LAN during work hours. -- http://mail.python.org/mailman/listinfo/python-list
Re: python list handling and Lisp list handling
Mark Tarver wrote: This page says that Python lists are often flexible arrays http://www.brpreiss.com/books/opus7/html/page82.html but also says that their representation is implementation dependent. As far as I see this should mean that element access in Python should run in constant time. Now if so this is a boon, because generally 'A list is a sequence of elements, but it is not a single primitive object; it is made of cons cells, one cell per element. Finding the nth element requires looking through n cons cells, so elements farther from the beginning of the list take longer to access. But it is possible to add elements to the list, or remove elements.' (from http://www.chemie.fu-berlin.de/chemnet/use/info/elisp/elisp_7.html) But are Python lists also indistinguishable from conventional Lisplists for list processing. For example, can I modify a Python list non-destructively? Are they equivalent to Lisp lists. Can CAR and CDR in Lisp be thought of as def car (x): return x[0] def cdr (x): return x[1:] The idea of a list in which elements can be accessed in constant time is novel to me. They are usually implemented as resizable arrays. In CPython great care has been taken to make appending average to constant time; however, inserting requires the later elements to be shifted up. In the way they are normally used they are fast. There are also queues and deques for when you want efficient queue or deque behaviour. -- http://mail.python.org/mailman/listinfo/python-list
Re: Large data arrays?
Hi John John Machin sjmac...@lexicon.net writes: On Apr 25, 1:14 am, Ole Streicher ole-usenet-s...@gmx.net wrote: John Machin sjmac...@lexicon.net writes: From my access pattern, it would be probably better to combine 25 rows into one slice and have one matrix where every cell contains 25 rows. Are there any objections about that? Can't object, because I'm not sure what you mean ... how many elements in a cell? Well, a matrix consists of cells? A 10x10 matrix has 100 cells. Yes yes but you said every cell contains 25 rows ... what's in a cell? 25 rows, with each row containing what? I mean: original cells. I have 100.000x4096 entries: (0,0) (0,1) ... (0,4095) (1,0) (1,1) ... (1,4095) ... (100.000,0) (100.000,1) ... (100.000,4095) This will be re-organized in a new matrix, containing 4096 columns (as before) and 4000 rows. The leftmost cell (first row, first col) in the new matrix then contains the array (0,0) (1,0) ... (24,0) The second column of the first row contains the array (0,1) (1,1) ... (24,1) and so on. The first column of the second row contains (25,0) ... (49,0) That way, I get a new matrix where every cell contains an array of 24 original cells. Disadvantage (what I see now when I write it down) is that this is bad for numpy since it deals with arrays instead of numbers in matrix positions. Best regards Ole -- http://mail.python.org/mailman/listinfo/python-list
Re: python list handling and Lisp list handling
Mark Tarver dr.mtar...@ukonline.co.uk writes: But are Python lists also indistinguishable from conventional Lisplists for list processing. Forgot to add: you might look at http://norvig.com/python-lisp.html Mark Tarver dr.mtar...@ukonline.co.uk writes: But are Python lists also indistinguishable from conventional Lisplists for list processing. They are very different. There is nothing like cons or nconc. You can't convert two lists to a single longer list with nconc, etc. -- http://mail.python.org/mailman/listinfo/python-list
Re: python list handling and Lisp list handling
Mark Tarver dr.mtar...@ukonline.co.uk writes: But are Python lists also indistinguishable from conventional Lisplists for list processing. For example, can I modify a Python list non-destructively? Are they equivalent to Lisp lists. Can CAR and CDR in Lisp be thought of as Python lists are vectors that automatically resize. You can append to the end in amortized constant time in the obvious way (i.e. the implementation allocates some extra space for expansion, and copies to an even bigger area if you run out of expansion room). You can insert and delete in the middle in linear time. This isn't as bad as it sounds because the Python interpreter is pretty slow, but the list insertion/deletion primitives are in C and are fast. -- http://mail.python.org/mailman/listinfo/python-list
mod_python form upload: permission denied sometimes...
I have a mod_python application that takes a POST file upload from a form. It works fine from my machine, other machines in my office and my home machine. It does not work from my bosses machine in a different city - he gets You don't have permission to access this on this server. In the logs, it's returned 403. I also have this error in error.log: Cannot traverse upload in /pythonapps/wiggle/form/upload because function form at 0x7fe7568e31b8 is not a traversable object, referer: ... Could this be a network level problem? If so, why does it work from my home machine but not my bosses machine?? The file to upload is quite large - 7MB. -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
Steven D'Aprano wrote: On Thu, 23 Apr 2009 21:51:42 -0400, Esmail wrote: set(a) == set(b)# test if a and b have the same elements # check that each list has the same number of each element # i.e. [1,2,1,2] == [1,1,2,2], but [1,2,2,2] != [1,1,1,2] for elem in set(a): a.count(elem) == b.count(elem) Ah .. this part would take care of different number of duplicates in the lists. Cool. At significant cost of extra work. Counting the number of times a single element occurs in the list is O(N). Counting the number of times every element occurs in the list is O(N**2). A frequency dict should be O(n) also, and hence faster than sorting. Sorting is O(N*log N), so for large lists, sorting will probably be much cheaper. -- http://mail.python.org/mailman/listinfo/python-list
Re: Help with code! Gamepad?
On Apr 24, 10:11 am, DC16 luster...@gmail.com wrote: On Apr 23, 4:03 pm, Mike Driscoll kyoso...@gmail.com wrote: On Apr 23, 6:46 am, DC16 luster...@gmail.com wrote: I am using pygame and OpenGL. How do I make a gamepad able to move the camera to a side of a cube on screen. Here is the code for keyboard use: import pygame from pygame.locals import * import sys from OpenGLLibrary import * pygame.init() Screen = (800,600) Window = glLibWindow(Screen,caption=Camera Test) View3D = glLibView3D((0,0,Screen[0],Screen[1]),45) View3D.set_view() Camera = glLibCamera([0,0.5,6],[0,0,0]) glLibColorMaterial(True) drawing = 0 Objects = [glLibObjCube(),glLibObjTeapot(),glLibObjSphere (64),glLibObjCylinder(0.5,1.0,64),glLibObjCone(0.5,1.8,64)] while True: key = pygame.key.get_pressed() for event in pygame.event.get(): if event.type == QUIT: pygame.quit() sys.exit() if event.type == KEYDOWN: if event.key == K_ESCAPE: pygame.quit() sys.exit() if event.key == K_RETURN: drawing += 1 if drawing == 5: drawing = 0 if event.key == K_1: glLibColor((255,255,255)) if event.key == K_2: glLibColor((255,0,0)) if event.key == K_3: glLibColor((255,128,0)) if event.key == K_4: glLibColor((255,255,0)) if event.key == K_5: glLibColor((0,255,0)) if event.key == K_6: glLibColor((0,0,255)) if event.key == K_7: glLibColor((128,0,255)) if key[K_LEFT]: Camera.set_target_pos([-6,0.5,0]) elif key[K_RIGHT]: Camera.set_target_pos([6,0.5,0]) elif key[K_UP]: Camera.set_target_pos([0,6,2]) elif key[K_DOWN]: Camera.set_target_pos([0,-6,2]) else: Camera.set_target_pos([0,0.5,6]) Camera.update() Window.clear() Camera.set_camera() Objects[drawing].draw() Window.flip() How do I change it so that a gampad can move the camera in the same way. (Ignore the colour changing code) Thanks, Dexter (DC16) BTW the code was originally by someone else. Try cross-posting to the pygame guys:http://www.pygame.org/wiki/info I read that pyglet will have some sort of gamepad support soon too, so you might want to check that project out as well. - Mike- Hide quoted text - - Show quoted text - I cannot find any code for gamepad/joypad on there. I guess I was thinking of this: http://pypi.python.org/pypi/jaraco.input/1.0 Mike -- http://mail.python.org/mailman/listinfo/python-list
Re: Raw command line arguments
En Fri, 24 Apr 2009 06:40:23 -0300, Enchanter ensoul.magaz...@gmail.com
escribió:
How to pass the raw command line arguments to the python?
That depends on the OS or the shell you're using.
Such as:
mypython.py txt -c Test Only {Help}
The arguments I hope to get is:
txt -c Test Only {Help} -- Keep the
quotation marks in the arguments.
I guess you're using Windows:
ggtype show.py
import sys
print sys.argv
ggpython show.py one txt -c Test Only {Help}
['show.py', 'one', 'txt', '-c', 'Test Only', '{Help}']
Two double quotes represent a single one. And you have to enclose the
whole argument in quotes too because of the space character.
--
Gabriel Genellina
--
http://mail.python.org/mailman/listinfo/python-list
Re: sorting two corresponding lists?
Just being pedantic here :) [items[x] for x in [i for i in map(values.index, new_values)]] Is the same as [items[x] for x in map(values.index, new_values)] It's also the same as [items[x] for x in [values.index(i) for i in new_values]] Which reduces to [items[values.index(i)] for i in new_values] All these variances prove how python amazing is, thanks! (Although 'i' is not a good choice of variable as it represents a value, not an index) Actually, I think 'i' indeed represents index of each sorted values in original values list Anyway it doesn't work well if the 'values' list has repeated values, e.g. items = ['spam', 'eggs', 'wafer'] values = [3, 7, 3] Yes, I didn't even think about this situation! I'm new to python too, as original poster Esmail, there are a lot of things to learn to be a real pythoner:) -- http://mail.python.org/mailman/listinfo/python-list
Re: first, second, etc line of text file
En Thu, 23 Apr 2009 18:50:06 -0300, Scott David Daniels scott.dani...@acm.org escribió: Gabriel Genellina wrote: En Wed, 25 Jul 2007 19:14:28 -0300, James Stroud jstr...@mbi.ucla.edu escribió: [nice recipe to retrieve only certain lines of a file] I think your time machine needs an adjustment, it spits things almost two years later :) -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Python servlet for Java applet ?
Hi guys. Is there a way to use a python application as the back end (ie rpc) for a Java based applet ? How does it work compared to a Java servlet with a Java applet ? Thanks -- http://mail.python.org/mailman/listinfo/python-list
confused with so many python package locations for imports
hello all, I was doing my first complete python packaging for my software and I am totally confused. I see, /usr/local/lib/python-2.6/site-packages and also dist-packages. Then I also see a directory called pyshare, then again site-packages in usr/lib/python (I am not even remembering correct paths for many such locations ). Now my question is, which the perfect place? I would like to know if I write a distutils based setup.py for my application, then which is the place which I should choose? happy hacking. Krishnakant. -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
Esmail wrote: What is the best way to compare the *contents* of two different lists regardless of their respective order? The lists will have the same number of items, and be of the same type. E.g. a trivial example (my lists will be larger), a=[1, 2, 3] b=[2, 3, 1] should yield true if a==b I suppose I could sort them and then compare them. I.e., sorted(a)==sorted(b) I am wondering if there is a more efficient/preferred way to do so. Thanks, Esmail -- http://mail.python.org/mailman/listinfo/python-list = Technically, == is reserved for identical, as in byte for byte same -If sorted(listA) == sorted(listB): - etc Is the preferred. While there are other ways, the ones I know of are much more computer intensive. Things like: get (next) line from file1 if checking it against each line of file2 yields a found loop else ... are a real I/O killers. Indexes are good but introduce a separate maintenance issue. By the way - does original order of original files count? If not, sorting AND KEEPING can speed up future things. Of course each method has its time and place of use and Python has some well oiled list search and list maintain routines of its own. List comparisons are most accurate when using presorted ones. (Some things don't lend themselves to sorting very well. Like paragraphs, books, chapters, computer programs, manuals, etc... These need the searchers (equivalent to the Unix diff) for checking equivalence.) HTH Steve -- http://mail.python.org/mailman/listinfo/python-list
PyQt4 - widget signal trouble
Hello, I'm trying to get my first PyQt4 application to work as intended, but it seems I'm stuck and out of ideas for now. The program is a simple GUI showing an image. If the image on disk change my intension is that the displayed image in my application also change accordingly. What works: The filesystem change is detected and my program prints out Change happened! what is the problem: The image shown in the application is not changed. What am I doing wrong here? Any ideas and suggestions are appreciated. Best regards, Joacim Thomassen My program: #!/usr/bin/python familyframe.py Simple photo frame for the desktop Author: Joacim Thomassen, 4/2-2009 License: AGPLv3+ Last change: 24/2-2009 from __future__ import division import sys from math import * from PyQt4.QtCore import * from PyQt4.QtGui import * import time import fcntl import os import signal fname = /home/joacim/.familyframe class Watcher(QObject): def handler(self, signum, frame): self.emit(SIGNAL(imageChange)) def __init__(self, parent=None): super(Watcher, self).__init__() signal.signal(signal.SIGIO, self.handler) fd = os.open(fname, os.O_RDONLY) fcntl.fcntl(fd, fcntl.F_SETSIG, 0) fcntl.fcntl(fd, fcntl.F_NOTIFY, fcntl.DN_MODIFY | fcntl.DN_CREATE | fcntl.DN_MULTISHOT) class ImageWidget(QLabel): def __init__(self, parent=None): super(QLabel, self).__init__(parent) self.image = QImage(/home/joacim/.familyframe/image.jpg) self.setMinimumSize(200, 200) self.setAlignment(Qt.AlignCenter) self.setPixmap(QPixmap.fromImage(self.image)) def reload(self): print Change happened! self.image.load(/home/joacim/.familyframe/image.jpg) self.setPixmap(QPixmap.fromImage(self.image)) self.update() class CentralWidget(QWidget): def __init__(self, parent=None): super(QWidget, self).__init__(parent) self.imagewidget = ImageWidget() self.box = QHBoxLayout() self.box.addWidget(self.imagewidget) self.setLayout(self.box) def reload(self): self.imagewidget.reload() class MainWindow(QMainWindow): def __init__(self, w, parent=None): super(MainWindow, self).__init__(parent) self.centralwidget = CentralWidget() self.setWindowTitle(Family Frame) self.setCentralWidget(self.centralwidget) self.connect(w, SIGNAL(imageChange), self.updateUi) self.show() def updateUi(self): self.centralwidget.reload() if __name__ == __main__: app = QApplication(sys.argv) w = Watcher() main = MainWindow(w) app.exec_() -- http://mail.python.org/mailman/listinfo/python-list
Re: Convert numpy.ndarray into normal array
In article 75dgm1f16hqn...@mid.dfncis.de, Johannes Bauer dfnsonfsdu...@gmx.de wrote: So now I want to copy the fits_pixels - pb_pixels. Doing pb_pixels = fits_pixels works and is insanely fast, however the picture looks all screwed-up (looks like a RGB picture of unititialized memory, huge chunks of 0s interleaved with lots of white noise). Doing the loop: for x in range(width): for y in range(height): pb_pixels[y, x] = fits_pixels[y, x] works as expected, but is horribly slow (around 3 seconds for a 640x480 picture). So now I've been trying to somehow convert the array in a fast manner, but just couldn't do it. What exactly is array anyways? I know array.array, but that's something completely different, right? Does anyone have hints on how to go do this? http://scipy.org/Mailing_Lists -- 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
Help AIX 5.3 build on Python-3.1a2
OPT=-O2 LDFLAGS=-s ./configure --prefix=/ptst --with-gcc=xlc_r -q64 --with-cxx=xlC_r -q64 --disable-ipv6 AR=ar -X64 --without-locale -- without-ctypes checking for --with-universal-archs... 32-bit checking MACHDEP... aix5 checking machine type as reported by uname -m... 00023AAA4C00 checking for --without-gcc... xlc_r -q64 checking for gcc... xlc_r -q64 checking for C compiler default output file name... a.out checking whether the C compiler works... yes checking whether we are cross compiling... no checking for suffix of executables... checking for suffix of object files... o checking whether we are using the GNU C compiler... no checking whether xlc_r -q64 accepts -g... yes checking for xlc_r -q64 option to accept ISO C89... none needed checking for --with-cxx-main=compiler... no checking for c++... no checking for g++... no checking for gcc... no checking for CC... no checking for cxx... no checking for cc++... no checking for cl... no checking how to run the C preprocessor... xlc_r -q64 -E checking for grep that handles long lines and -e... /usr/bin/grep checking for egrep... /usr/bin/grep -E checking for AIX... yes checking for --with-suffix... checking for case-insensitive build directory... no checking LIBRARY... libpython$(VERSION).a checking LINKCC... $(srcdir)/Modules/makexp_aix Modules/python.exp . $ (LIBRARY); $(PURIFY) $(MAINCC) checking for --enable-shared... no checking for --enable-profiling... checking LDLIBRARY... libpython$(VERSION).a checking for ranlib... ranlib checking for ar... ar -X64 checking for svnversion... not-found checking for a BSD-compatible install... ./install-sh -c checking for --with-pydebug... no checking whether xlc_r -q64 accepts -OPT:Olimit=0... no checking whether xlc_r -q64 accepts -Olimit 1500... no checking whether pthreads are available without options... yes checking for ANSI C header files... yes checking for sys/types.h... yes checking for sys/stat.h... yes checking for stdlib.h... yes checking for string.h... yes checking for memory.h... yes checking for strings.h... yes checking for inttypes.h... yes checking for stdint.h... yes checking for unistd.h... yes checking asm/types.h usability... no checking asm/types.h presence... no checking for asm/types.h... no checking conio.h usability... no checking conio.h presence... no checking for conio.h... no checking curses.h usability... yes checking curses.h presence... yes checking for curses.h... yes checking direct.h usability... no checking direct.h presence... no checking for direct.h... no checking dlfcn.h usability... yes checking dlfcn.h presence... yes checking for dlfcn.h... yes checking errno.h usability... yes checking errno.h presence... yes checking for errno.h... yes checking fcntl.h usability... yes checking fcntl.h presence... yes checking for fcntl.h... yes checking grp.h usability... yes checking grp.h presence... yes checking for grp.h... yes checking ieeefp.h usability... no checking ieeefp.h presence... no checking for ieeefp.h... no checking io.h usability... no checking io.h presence... no checking for io.h... no checking langinfo.h usability... yes checking langinfo.h presence... yes checking for langinfo.h... yes checking libintl.h usability... yes checking libintl.h presence... yes checking for libintl.h... yes checking ncurses.h usability... no checking ncurses.h presence... no checking for ncurses.h... no checking poll.h usability... yes checking poll.h presence... yes checking for poll.h... yes checking process.h usability... no checking process.h presence... no checking for process.h... no checking pthread.h usability... yes checking pthread.h presence... yes checking for pthread.h... yes checking shadow.h usability... no checking shadow.h presence... no checking for shadow.h... no checking signal.h usability... yes checking signal.h presence... yes checking for signal.h... yes checking for stdint.h... (cached) yes checking stropts.h usability... yes checking stropts.h presence... yes checking for stropts.h... yes checking termios.h usability... yes checking termios.h presence... yes checking for termios.h... yes checking thread.h usability... no checking thread.h presence... no checking for thread.h... no checking for unistd.h... (cached) yes checking utime.h usability... yes checking utime.h presence... yes checking for utime.h... yes checking sys/audioio.h usability... no checking sys/audioio.h presence... no checking for sys/audioio.h... no checking sys/bsdtty.h usability... no checking sys/bsdtty.h presence... no checking for sys/bsdtty.h... no checking sys/epoll.h usability... no checking sys/epoll.h presence... no checking for sys/epoll.h... no checking sys/event.h usability... no checking sys/event.h presence... no checking for sys/event.h... no checking sys/file.h usability... yes checking sys/file.h presence... yes checking for sys/file.h... yes checking sys/loadavg.h usability... no checking sys/loadavg.h presence... no checking for sys/loadavg.h... no checking
Re: mailbox.mbox.add() sets access time as well as modification time
In message gtudnry7tappu2zunz2dnuvz_h6dn...@posted.visi, Grant Edwards wrote: AFAIK, atimemtime has been the standard way to determine when an mbox contains new mail for at least 20 years. Doesn't apply to maildir though, does it? Updating atime adds a lot of filesystem overhead; that's why the relatime option was invented http://lwn.net/Articles/244829/. But better still is not to bother. -- http://mail.python.org/mailman/listinfo/python-list
Re: best way to compare contents of 2 lists?
On Fri, 24 Apr 2009 10:39:39 -0700, norseman wrote:
Technically, == is reserved for identical, as in byte for byte same
Really? Then how do you explain these?
u'abc' == 'abc'
True
1 == 1.0
True
2L == 2
True
import decimal
decimal.Decimal('42') == 42
True
Here's one to think about:
d1 = {-1: None, -2: None}
d2 = {-2: None, -1: None}
print d1, d2
{-2: None, -1: None} {-1: None, -2: None}
d1 == d2
True
If d1 and d2 are equal and both are dictionaries with the same keys and
same values, why do they print in different orders?
--
Steven
--
http://mail.python.org/mailman/listinfo/python-list
Re: python list handling and Lisp list handling
On 24 Apr, 17:19, Paul Rubin http://phr...@nospam.invalid wrote: Mark Tarver dr.mtar...@ukonline.co.uk writes: But are Python lists also indistinguishable from conventional Lisplists for list processing. Forgot to add: you might look athttp://norvig.com/python-lisp.html Mark Tarver dr.mtar...@ukonline.co.uk writes: But are Python lists also indistinguishable from conventional Lisplists for list processing. They are very different. There is nothing like cons or nconc. You can't convert two lists to a single longer list with nconc, etc. Ah; so this def cons (x,y): return [x] + y is not accurate? Mark -- http://mail.python.org/mailman/listinfo/python-list
Re: mailbox.mbox.add() sets access time as well as modification time
On 2009-04-24, MRAB goo...@mrabarnett.plus.com wrote: [snip] The access time is the time it was last accessed, ie read or modified. Usually. The modification time is the time it was last modified. Usually. The access time can never be before the modification time because it must be accessed in order to be modified! Nonsense. You can set atime and mtime to anything you want. Well, yes, you can always change atime and mtime and make it look like something happened at a different time to when it actually happened... Yup. And that's what one does when writing to an mbox format mailbox. SOP for writing to to an mbox formatted mailbox is to preserve the atime (changing only the mtime) so that other programs know that that there is new mail in the mbox. I know mutt works that way, and I believe that the you've got new mail features in some shells work that way. AFAIK, atimemtime has been the standard way to determine when an mbox contains new mail for at least 20 years. So atime is used to indicate when it was last read, not last accessed? Hmm... Unfortunately, that's how mbox works. It's an ugly hack, but if one didn't care about backwards-compatiblity with old e-mail apps, then one would use a less broken mailbox format like maildir. -- Grant Edwards grante Yow! I smell like a wet at reducing clinic on Columbus visi.comDay! -- http://mail.python.org/mailman/listinfo/python-list
Re: mailbox.mbox.add() sets access time as well as modification time
On 2009-04-24, Lawrence D'Oliveiro l...@geek-central.gen.new_zealand wrote: In message gtudnry7tappu2zunz2dnuvz_h6dn...@posted.visi, Grant Edwards wrote: AFAIK, atimemtime has been the standard way to determine when an mbox contains new mail for at least 20 years. Doesn't apply to maildir though, does it? Nope. With maildir, there's a completely separate directory where one puts new messages. Updating atime adds a lot of filesystem overhead; that's why the relatime option was invented http://lwn.net/Articles/244829/. The relatime should cut down a great deal on system overhead and yet still preserves the atime/mtime semantics used by mbox clients. But better still is not to bother. -- Grant Edwards grante Yow! I wonder if I could at ever get started in the visi.comcredit world? -- http://mail.python.org/mailman/listinfo/python-list
Re: repost: http web page fetch question
grocery_stocker wrote: Given the following... [cdal...@localhost oakland]$ more basic.py snip How do I modify it so that it runs every hour on the hour. I'd probably use cron, but here's one way. Emile - import sched import time scheduler = sched.scheduler(time.time, time.sleep) def print_event(count,rescheduler): print 'EVENT:', time.time(), count rescheduler.enter(2,1,print_event,(count+1,rescheduler)) print 'START:', time.time() scheduler.enter(2, 1, print_event, (1,scheduler)) scheduler.run() -- http://mail.python.org/mailman/listinfo/python-list
Re: and [True,True] -- [True, True]?????
Of course dicts and sets are sequences. But there are also sequences on which len doesn't work. That was my intuition, too. But Python takes a different stance: It's a sequence if it can be indexed by numbers in range(len(seq)). Neither dicts nor sets can be indexed that way. Regards, Martin -- http://mail.python.org/mailman/listinfo/python-list
