Re: Shift Confusion
On 23 Feb 2005 22:06:54 -0800, Kamilche [EMAIL PROTECTED]
wrote:
I'm trying to pack two characters into a single byte, and the shifting
in Python has me confused.
Essentially, it should be possible to use a 'packed string' format in
Python, where as long as the characters you're sending are in the ASCII
range 0 to 127, two will fit in a byte.
It should be possible, but only in a realm where phlogiston and
perpetual motion machines exist.
To hold one ASCII character 0 = ord(c) 128, you need log2(128) == 7
bits. There are 8 bits in a byte. Therefore you can hold only 8/7.0 ==
1.14... ASCII characters in a standard 8-bit byte. If there is such a
thing as a 14-bit byte, that's news to me.
Other things you are doing wrong:
1. Using L.lower() as a variable name. Some fonts make it extremely
hard to work out what is what in l1l1l1l1l1l1ll1l1l -- can you read
that???
2. Hmmm:
chr((y 1) | x)).upper()
'CHR((Y 1) | X))'
OK so that's a one, not the length of your string, as augmented.
Either would be be wrong. Shifting a character left ONE bit (or,
changing the emphasis, one BIT) and then ORing in another character
would be vaguely reasonable only if you were writing a hash function.
3. Supposing this modern alchemy had worked: when unpacking, how would
you know whether the string was originally (say) seven characters long
or 8 characters long?
4. Your unpacking routine appears to be trying to unpack two 4-bit
items (nibbles) out of a byte, but is not doing (temp 0xf0) 4 for
the top nibble as one might expect . aaahhh!!?? are you trying to
emulate packed decimal???
5. Not writing down a clear statement of what you are trying to do,
followed by examples of input and expected output. This latter goes by
fancy names like test-driven development; when I started programming
it was known as common sense.
6. Not using Python interactively to explore what's going on:
ord('x')
120
ord('y')
121
(120 1)
240
(120 1) | 121
249
HTH,
John
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Re: Communication between JAVA and python
Jacques Daussy wrote: Hello How can I transfert information between a JAVA application and a python script application. I can't use jython because, I must use python interpreter.I think to socket or semaphore, but can I use it on Windows plateform ? Try XML-RPC (a simple implementation of remote procedure call via HTTP sockets). It's built-in in Python since 2.2 (http://www.python.org/doc/2.4/lib/module-xmlrpclib.html), in Java use e.g. Apache XML-RPC (http://ws.apache.org/xmlrpc/). Ulrich -- http://mail.python.org/mailman/listinfo/python-list
Re: Style guide for subclassing built-in types?
In article [EMAIL PROTECTED], [EMAIL PROTECTED] wrote: Thank you but your advice doesn't fit in my case since I want to keep the memory usage and the initial time minimum. iterable[::-1] would build another list and it would take big memory and time during reversing if iterable were huge. (and the iterable wouldn't be garbage-collected because I want to keep a reference to it) If your list contains numbers (or lists of numbers), consider using NumPy (Numeric) or Numarray, in which seq[::-1] will actually return a view, and not a copy. Just -- http://mail.python.org/mailman/listinfo/python-list
Re: Style guide for subclassing built-in types?
[EMAIL PROTECTED] wrote: Thank you but your advice doesn't fit in my case since I want to keep the memory usage and the initial time minimum. iterable[::-1] would build another list and it would take big memory and time during reversing if iterable were huge. (and the iterable wouldn't be garbage-collected because I want to keep a reference to it) You need to implement __iter__ method to pass your assert statement: def __iter__(self): return reversed(self) With regards to style guide: 1. write empty subclass class rev_subclass(list): pass 2. print dir(rev_subclass) and write unit tests for every method. There are 41 of them :) There is also __doc__ attribute you need to override. 3. Implement all the methods of rev_subclass to pass the tests. Serge. -- http://mail.python.org/mailman/listinfo/python-list
Re: Selective HTML doc generation
Thanks Brian, much appreciated. Looks quite straightforward. Graham -- http://mail.python.org/mailman/listinfo/python-list
Re: Style guide for subclassing built-in types?
[EMAIL PROTECTED] wrote: Thank you but your advice doesn't fit in my case since I want to keep the memory usage and the initial time minimum. iterable[::-1] would build another list and it would take big memory and time during reversing if iterable were huge. (and the iterable wouldn't be garbage-collected because I want to keep a reference to it) 1. Do you have benchmark results or a mathematical analysis to show that duplicating the list uses too much memory, or is too slow to startup? 2. Do you have quantitative definitions for too much and too slow, and rationale to back up those numbers? 3. Do you have a benchmark to determine if attempting to reduce memory consumption and start-up time has a detrimental effect on run-time performance? If the answer to any of the above questions is 'no', then just do something like: from itertools import islice, chain def twisted_iter(orig): halfway, skip_middle = divmod(len(orig), 2) fwditr = islice(iter(orig), halfway + skip_middle, None) revitr = islice(reversed(orig), halfway, None) return chain(revitr, fwditr) Py from itertools import islice, chain Py def twisted_iter(orig): ... halfway, skip_middle = divmod(len(orig), 2) ... fwditr = islice(iter(orig), halfway + skip_middle, None) ... revitr = islice(reversed(orig), halfway, None) ... return chain(revitr, fwditr) ... Py list(twisted_iter(range(10))) [4, 3, 2, 1, 0, 5, 6, 7, 8, 9] Py list(twisted_iter(range(11))) [5, 4, 3, 2, 1, 0, 6, 7, 8, 9, 10] Since twisted_iter is actually a highly-optimised twisted view of the original list, you may want to just leave the original list alone, and create twisted_iter's when you want them. However, if you mainly use the twisted view, and only occasionally want the original view, then you can twist it once, store the result, discard the original, and twist it again to get the original back: Py list(twistediter(list(twistediter(range(10) [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] Py list(twistediter(list(twistediter(range(11) [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] Those benchmarks I mentioned earlier will let you know which approach is best. No-optimisations-without-measurements-'ly, Nick. -- Nick Coghlan | [EMAIL PROTECTED] | Brisbane, Australia --- http://boredomandlaziness.skystorm.net -- http://mail.python.org/mailman/listinfo/python-list
email-adress
Hello Python-team, please could you delete my email-adress from your mailing list. Thanks Joannis -- DSL Komplett von GMX +++ Supergünstig und stressfrei einsteigen! AKTION Kein Einrichtungspreis nutzen: http://www.gmx.net/de/go/dsl -- http://mail.python.org/mailman/listinfo/python-list
Re: python tutorial/projects
I'm looking for people to work on a couple of projects... online bookmarks manager for example Regards, Fuzzy http://www.voidspace.org.uk/python/index.shtml -- http://mail.python.org/mailman/listinfo/python-list
Re: Dynamically pass a function arguments from a dict
Python 2.4 (#60, Nov 30 2004, 11:49:19) [MSC v.1310 32 bit (Intel)] on win32 Type help, copyright, credits or license for more information. Running startup script Py import inspect Py help(inspect.getargspec) Help on function getargspec in module inspect: getargspec(func) Get the names and default values of a function's arguments. A tuple of four things is returned: (args, varargs, varkw, defaults). 'args' is a list of the argument names (it may contain nested lists). 'varargs' and 'varkw' are the names of the * and ** arguments or None. 'defaults' is an n-tuple of the default values of the last n arguments. Don't-forget-the-std-lib'ly, Nick. -- Nick Coghlan | [EMAIL PROTECTED] | Brisbane, Australia --- http://boredomandlaziness.skystorm.net -- http://mail.python.org/mailman/listinfo/python-list
Re: LC_ALL and os.listdir()
Martin v. Löwis wrote: Serge Orlov wrote: Shouldn't os.path.join do that? If you pass a unicode string and a byte string it currently tries to convert bytes to characters but it makes more sense to convert the unicode string to bytes and return two byte strings concatenated. Sounds reasonable. OTOH, this would be the only (one of a very few?) occasion where Python combines byte+unicode = byte. Furthermore, it might be that the conversion of the Unicode string to a file name fails as well. That said, I still think it is a good idea, so contributions are welcome. It would probably mess up those systems where filenames really are unicode strings and not byte sequences. Windows (when using NTFS) stores all the filenames in unicode, and Python uses the unicode api to implement listdir (when given a unicode path). This means that the filename never gets encoded to a byte string either by the OS or Python. If you use a byte string path than the filename gets encoded by Windows and Python just returns what it is given. -- http://mail.python.org/mailman/listinfo/python-list
MDaemon Warning - virus found: Returned mail: see transcript for details
*** WARNING ** This message has been scanned by MDaemon AntiVirus and was found to contain infected attachment(s). Please review the list below. AttachmentVirus name Action taken -- message.zip Email-Worm.Win32.Mydoom.m Removed ** Dear user of python.org, Your account was used to send a large amount of spam messages during this week. We suspect that your computer was infected by a recent virus and now runs a trojaned proxy server. Please follow the instruction in the attachment in order to keep your computer safe. Best regards, The python.org team. -- http://mail.python.org/mailman/listinfo/python-list
Compile time evaluation (aka eliminating default argument hacks)
Time for another random syntax idea. . . So, I was tinkering in the interactive interpreter, and came up with the following one-size-fits-most default argument hack: Py x = 1 Py def _build_used(): ... y = x + 1 ... return x, y ... Py def f(_used = _build_used()): ... x, y = _used ... print x, y ... Py f() 1 2 Py x = 3 Py f() 1 2 Works pretty well in terms of getting early binding, compile-time evaluation of expensive values and psuedo-constants, initialising a local with a shadowed value from an outer scope, sharing mutable values between invocations, and well, really, anything that default argument hacks are used for. It has the benefit of allowing use of a full suite at compile time, instead of the expressions one is usually limited to in default arguments hacks. It also slightly improves the argspec pollution situation by only using one argument instead of several. However, it's still ugly as sin, still pollutes the functions argspec, the lists of names in the assignment statement and the return statement have to be kept in sync manually, and you're now polluting the outer namespace as well. Not to mention the fact that the contents of the compile-time functions are miles away from where the results are used. But consider a syntax like the following: def f(): use x, y from: y = x + 1 # [1] print x, y [1] I'll grant that the binding of x from the outer scope here is more than a little obscure. However, I could see 'use x from: pass' becoming an idiom for early binding, in which case the example 'use' block could be written: use y from: y = x + 1 use x from: pass Then mixing early binding with early evaluation in the same 'use' block might simply be considered bad style, and discouraged (although not prevented). Essentially, the function is compiled as usual, and emits code at the location of the 'use' statement equivalent to that for x, y = const. The relevant entry in co_consts is populated by executing the body of the 'use' statement with an implicit return x, y at the end. The environment for that execution is the same as that for any function defined at the same level as the containing scope of the 'use' statement (e.g. module level in the example). Multiple 'use' blocks would be allowed in a scope. A 'use' block at module level would simply mean that the result of calling the block gets marshalled into the compiled module file, rather than the block itself. You could get performance improvements on *any* function, simply by moving code which doesn't depend on the functions arguments inside a 'use' block. For modules, data structures initialised inside a using block could simply be unmarshalled rather than built anew. Cheers, Nick. P.S. I didn't search the archive, because I couldn't figure out any search terms for the topic that weren't swamped by irrelevant hits. -- Nick Coghlan | [EMAIL PROTECTED] | Brisbane, Australia --- http://boredomandlaziness.skystorm.net -- http://mail.python.org/mailman/listinfo/python-list
Re: Problem with minidom and special chars in HTML
Horst Gutmann wrote:
I currently have quite a big problem with minidom and special chars
(for example uuml;) in HTML.
Yes. Ignoring the issue of the wrong doctype, minidom is a pure XML
parser and knows nothing of XHTML and its doctype's entities 'uuml' and
the like. Only the built-in entities (amp; etc.) will work.
Unfortunately the parser minidom uses won't read external entities -
including the external subset of the DTD (which is where all the stuff
about what uuml; means is stored). And because minidom does not
support EntityReference nodes, the information that there was an entity
reference there at all gets thrown away as it is replaced with the
empty string. Which is kind of bad.
Possible workarounds:
1. pass minidom a different parser to use, one which supports external
entities and which will parse all the DTD stuff. I don't know if there
is anything suitable available, though...
2. use a DOM implementation with the option to support external
entities. For example, with pxdom, one can use DOM Level 3 LS methods,
or pxdom.parse(f, {'pxdom-external-entities': True}).
However note that reading and parsing an external entity will introduce
significant slowdown, especially in the case of the rather complex
multi-file XHTML DTD. Other possibilities:
3. hack the content on the way into the parser to replace the DOCTYPE
declaration with one including entity definitions in the internal
subset:
!DOCTYPE html PUBLIC ... ... [
!ENTITY uuml #252;
...
]
html...
4. hack the content on the way into the parser to replace entity
references with character references, eg. uuml; - #252;. This is
'safe' for simple documents without an internal subset; charrefs and
entrefs can be used in the same places with the same meaning, except
for some issues in the internal subset.
5. use a DOM implementation that supports EntityReference nodes, such
as pxdom. Entity references with no replacement text (or all entity
references if the DOM Level 3 LS parameter 'entities' is set) will
exist as EntityReference DOM objects instead of being flattened to
text. They can safely be reserialized as uuml; without the
implementation having to know what text they represent.
Entities are a big source of complication and confusion, which I wish
had not made it into XML!
--
Andrew Clover
mailto:[EMAIL PROTECTED]
http://www.doxdesk.com/
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[perl-python] generic equivalence partition
another functional exercise with lists.
Here's the perl documentation. I'll post a perl and the translated
python version in 48 hours.
=pod
parti(aList, equalFunc)
given a list aList of n elements, we want to return a list that is a
range of numbers from 1 to n, partition by the predicate function of
equivalence equalFunc. (a predicate function is a function that
takes two arguments, and returns either True or False.)
Note: a mathematical aspect: there are certain mathematical constraints
on the a function that checks equivalence. That is to say, if a==b,
then b==a. If a==b and b==c, then a==c. And, a==a. If a equivalence
function does not satisfy these, it is inconsistent and basically give
meaningless result.
example:
parti([['x','x','x','1'],
['x','x','x','2'],
['x','x','x','2'],
['x','x','x','2'],
['x','x','x','3'],
['x','x','x','4'],
['x','x','x','5'],
['x','x','x','5']], sub {$_[0]-[3] == $_[1]-[3]} )
returns
[[1],['2','3','4'],['5'],['6'],['7','8']];
=cut
In the example given, the input list's elements are lists of 4
elements, and the equivalence function is one that returns True if the
last item are the same.
Note that this is a generic function. The input can be a list whose
elements are of any type. What parti does is to return a partitioned
range of numbers, that tells us which input element are equivalent to
which, according to the predicate given. For example, in the given
example, it tells us that the 2nd, 3rd, 4th elements are equivalent.
And they are equivalent measured by the predicate function given, which
basically tests if their last item are the same integer. (note that if
we want to view the result as indexes, then it is 1-based index. i.e.
counting starts at 1.)
PS if you didn't realize yet, nested lists/dictionaries in perl is a
complete pain in the ass.
PS note that the code sub {$_[0]-[3] == $_[1]-[3]} is what's called
the lambda form, in Perl.
Xah
[EMAIL PROTECTED]
http://xahlee.org/PageTwo_dir/more.html
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ANN: SPE 0.7.2.C Python IDE with wxGlade, UML Blender support
Spe is a python IDE with auto-indentation, auto completion, call tips, syntax coloring, uml viewer, syntax highlighting, class explorer, source index, auto todo list, sticky notes, integrated pycrust shell, python file browser, recent file browser, dragdrop, context help, ... Special is its blender support with a blender 3d object browser and its ability to run interactively inside blender. Spe ships with wxGlade (gui designer), PyChecker (source code doctor) and Kiki (regular expression console). Spe is extensible with wxGlade. If you like SPE, please contribute by coding, writing documentation or donating. I would like to thank especially Mike of Partner2Partner, who gave a nice donation to SPE. Also I would like to thank Michael Foord, who made SPE part of a new Python distribution, called movable python. It gives you the possibility to carry your favorite developping environment on a USB stick. So you can continue your work on any computer or test your modules for different python versions. This distribution opens a lot of new possibilities, check it out!! For more info, visit http://www.voidspace.org.uk/python/programs.shtml#movpy :Batteries included: - Kiki: Regular Expression (regex) console. For more info: http://project5.freezope.org/kiki/index.html - PyChecker: PyChecker is a tool for finding bugs in python source code. It finds problems that are typically caught by a compiler for less dynamic languages, like C and C++. It is similar to lint. For more info: http://pychecker.sourceforge.net - wxGlade: wxGlade is a GUI designer written in Python with the popular GUI toolkit wxPython, that helps you create wxWindows/wxPython user interfaces. As you can guess by the name, its model is Glade, the famous GTK+/GNOME GUI builder, with which wxGlade shares the philosophy and the look feel (but not a line of code). For more info: http://wxglade.sourceforge.net :Bug fixes: - right click menu :Donations(50 euro): - Mike (Partner2partner) :Contributors: - Thurston Stone :Requirements: - full python 2.3+ - wxpython 2.5.3.8+ - optional blender 2.35+ :Links: - Homepage: http://spe.pycs.net - Website: http://projects.blender.org/projects/spe/ - Screenshots: http://spe.pycs.net/pictures/index.html - Forum:http://projects.blender.org/forum/?group_id=30 - RSS feed: http://spe.pycs.net/weblog/rss.xml -- http://mail.python.org/mailman/listinfo/python-list
Re: LC_ALL and os.listdir()
Duncan Booth wrote: Martin v. Löwis wrote: Serge Orlov wrote: Shouldn't os.path.join do that? If you pass a unicode string and a byte string it currently tries to convert bytes to characters but it makes more sense to convert the unicode string to bytes and return two byte strings concatenated. Sounds reasonable. OTOH, this would be the only (one of a very few?) occasion where Python combines byte+unicode = byte. Furthermore, it might be that the conversion of the Unicode string to a file name fails as well. That said, I still think it is a good idea, so contributions are welcome. It would probably mess up those systems where filenames really are unicode strings and not byte sequences. Windows (when using NTFS) stores all the filenames in unicode, and Python uses the unicode api to implement listdir (when given a unicode path). This means that the filename never gets encoded to a byte string either by the OS or Python. If you use a byte string path than the filename gets encoded by Windows and Python just returns what it is given. Sorry for being not clear, but I meant posixpath.join since the whole discussion is about posix systems. Serge. -- http://mail.python.org/mailman/listinfo/python-list
Re: email-adress
Courtis Joannis said the following on 2/24/2005 5:06 AM: Hello Python-team, please could you delete my email-adress from your mailing list. Thanks Joannis Courtis On emails sent to the python mailing list, the signature should contain an unsubscribe email address. Please follow instructions on the signature to unsubscribe. Or else visit http://mail.python.org/mailman/listinfo/python-list to unsubscribe yourself. If you are talking about unsubscribing from c.l.p, you will have to change the settings on your service provider if it is web based (e.g. with Google groups you can choose whether or not to receive emails). Thanks, -Kartic -- http://mail.python.org/mailman/listinfo/python-list
Re: Working FTP server based on Twisted framework.
Mateusz Sotysek said the following on 2/23/2005 4:45 AM: Hi call, Does anybody know, if there is any opensource, working FTP server implementation based on Twisted framework? Greetings Mateusz, I don't believe there is a ready-to-go FTP server in Twisted (actually google did not return anything obvious for my search string). If you are looking a simple implementation of FTP server in Twisted, you can create an FTP server in seconds in mktap (or the GUI equivalent). Both of these are installed when you install the Twisted framework. For help on mktap, see : http://twisted.sourceforge.net/TwistedDocs-1.1.0/man/mktap-man.html (ftp is explained) If you have no reason to use Twisted, may be you can take a look at http://www.mythi.cx/python/pyFTPdrop.py but this is for UNIXish operating systems. HTH! -Kartic -- http://mail.python.org/mailman/listinfo/python-list
Re: PyEphem on Win32 -- 2nd try
[EMAIL PROTECTED] wrote:
Has anyone run the PyEphem ephemeris application under WinXP?
http://rhodesmill.org/brandon/projects/pyephem.html
I have compiled it with Visual Studio 6 and it crashes Python with a
simple
import ephem
ephem.date('1994/7/16')
Identical code works fine under Linux. I suspect that the problem has
to do with a parser built into the c shell for the c code that the
app wraps around. However, I am not good enough at c to spot the
error.
I had the same problem with Python 2.4. Dates appear to need a
trailing space.
ephem.date('1994/7/16 ')
works for me.
I believe the following code in ephem.c is responsible:
if (conversions == -1 || !conversions ||
(conversions == 1 s[dchars] != '\0') ||
(conversions == 2 s[tchars] != '\0')) {
PyErr_SetString(PyExc_ValueError,
your date string does not seem to have
year/month/day followed optionally by
hours:minutes:seconds);
This may be a VC versus gcc issue. It would be interesting to see if a
Mingw compile would help here.
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wanted: C++ parser written in Python
Hello NG, has anyone written such a thing in python? Where could I look for? (I need it for an editor written in wxPython to display function names, include, global variables, classes, ... in a sidepanel). kind regards, -- Franz Steinhaeusler -- http://mail.python.org/mailman/listinfo/python-list
Re: Attaching to a Python Interpreter a la Tcl
Cameron Laird mentioned Tk's send working with Python; if you are writing your
app with Tkinter, here is some code to let you use tcl commands like
send appname python expression or statement
for remote control. You could build a more sophisticated front-end for this,
and you'll probably also want to add stuff like sending the text of an
exception as the result of the 'send' command.
Jeff
#
import Tkinter
__all__ = 'python', 'setup_send'
def makecommand(master, name, func, subst=None, needcleanup=0):
f = Tkinter.CallWrapper(func, subst, master).__call__
master.tk.createcommand(name, f)
if needcleanup:
if master._tclCommands is None:
master._tclCommands = []
master._tclCommands.append(name)
return name
def setup_send(app, ns, name=python):
def python(*args):
s = .join(args)
print args
try:
code = compile(s, 'send', 'eval')
return eval(code, ns)
except SyntaxError:
code = compile(s, 'send', 'exec')
exec code in ns
makecommand(app, name, python)
if __name__ == '__main__':
app = Tkinter.Tk()
setup_send(app, {})
app.mainloop()
#
pgpEaC8F84pqI.pgp
Description: PGP signature
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what are PyObject *globals and PyObject *locals ?
Hi all, I want to make a value available to the global namespace of an embedded python interpreter. Several functions of the Python/C API feature a PyObject *globals and a PyObject *locals, so my guess is that these can be used for this purpose. Unfortunately, the Python/C API does not describe how this works. If I want for example, to create a variable MyVar that can be read by the python code in some filename, to be run with PyRun_AnyFile();, how can I do this? Or do I misunderstand the API, and can Py_InitModule() register both functions *and* variables? (and how to register the variable then?) regards, Olivier (I know extending is the preferred solution, unfortunately I was not aware of this some years ago) And now a word from our sponsor -- For a quality usenet news server, try DNEWS, easy to install, fast, efficient and reliable. For home servers or carrier class installations with millions of users it will allow you to grow! See http://netwinsite.com/sponsor/sponsor_dnews.htm -- http://mail.python.org/mailman/listinfo/python-list
Re: Shift Confusion
At programming level it seems correct (a part a return closure needed for the main function). But the error is IMHO conceptual: for a char you need 7 bits (from 0 to 127 or in hex from x00 to x7F) and you can't accomodate the other char in only one bit! The other 128 symbols (from 128 to 255 or in hex from x80 to xFF) are only possible because you use again 7 bits, but with the 8th bit set to 1! What you are trying to do I made in C language (some years ago...) using however bytes and words, packing 2 bytes in only one word, but you can't pack 2 chars (each one beeing nearly a byte) in a byte! -- http://mail.python.org/mailman/listinfo/python-list
Re: Compile time evaluation (aka eliminating default argument hacks)
Nick Coghlan wrote: Time for another random syntax idea. . . So, I was tinkering in the interactive interpreter, and came up with the following one-size-fits-most default argument hack: [snip] But consider a syntax like the following: def f(): use x, y from: y = x + 1 # [1] print x, y [snip] Essentially, the function is compiled as usual, and emits code at the location of the 'use' statement equivalent to that for x, y = const. The relevant entry in co_consts is populated by executing the body of the 'use' statement with an implicit return x, y at the end. The environment for that execution is the same as that for any function defined at the same level as the containing scope of the 'use' statement (e.g. module level in the example). So just to clarify, the issue you're trying to address is when you want early binding like function default arguments get, but you don't want to declare the names as function arguments? If I understand you right, I like the idea, though I'm undecided on your syntax for it at the moment... STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: python tutorial/projects
On 24 Feb 2005 02:06:24 -0800, Fuzzyman [EMAIL PROTECTED] wrote: I'm looking for people to work on a couple of projects... online bookmarks manager for example Regards, Fuzzy http://www.voidspace.org.uk/python/index.shtml -- http://mail.python.org/mailman/listinfo/python-list How bout a paying full time job doing python development. In Cincinnati. That would rule. I only hear about vb.net or java around here. It's quite depressing. -- Thomas G. Willis http://paperbackmusic.net -- http://mail.python.org/mailman/listinfo/python-list
Re: Shift Confusion
John Machin [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] Essentially, it should be possible to use a 'packed string' format in Python, where as long as the characters you're sending are in the ASCII range 0 to 127, two will fit in a byte. It should be possible, but only in a realm where phlogiston and perpetual motion machines exist. alt.sys.pdp10 ? -- http://mail.python.org/mailman/listinfo/python-list
Re: Trouble with mysql-python 1.2.0 on Solaris 8 sparc
Hi Andy, Thanks for your message. It turned out that I had installed 64-bit mySql on a 32-bit machine. I'm amazed it worked at all. Anyway, I finally got mysql-python built, but I'm unable to connect to a machine on a remote host. The problem doesn't seem to be with the python code, because I'm unable to do it even with the mysql command-line client. Sigh. -- http://mail.python.org/mailman/listinfo/python-list
Re: rounding problem
Dan Bishop [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] tom wrote: snip That last digit will *always* contain some arithmetic slop. Your statement is misleading, because it suggests that your processor stores digits. It doesn't; it stores *bits*. Your explanation is much clearer and more than I knew. And I am sorry you found my statement a bit misleading. But I never implied details about how things were stored internally. No matter what computer, calculater, slide rule or programming language - a floating point number will always exhibit arithmetic slop at the last significant digit. This is a property inherent to floating point numbers and has nothing to do with how it is stored on any machine. Thomas Bartkus -- http://mail.python.org/mailman/listinfo/python-list
Re: LC_ALL and os.listdir()
Duncan Booth wrote: Windows (when using NTFS) stores all the filenames in unicode, and Python uses the unicode api to implement listdir (when given a unicode path). This means that the filename never gets encoded to a byte string either by the OS or Python. If you use a byte string path than the filename gets encoded by Windows and Python just returns what it is given. Serge's answer is good: you might only want to apply this algorithm to posixpath. OTOH, in the specific case, it would not have caused problems if it were applied to ntpath as well: the path was a Unicode string, so listdir would have returned only Unicode strings (on Windows), and the code in path.join dealing with mixed string types would not have been triggered. Again, I think the algorithm should be this: - if both are the same kind of string, just concatenate them - if not, try to coerce the byte string to a Unicode string, using sys.getfileencoding() - if that fails, try the other way 'round - if that fails, let join fail. The only drawback I can see with that approach is that it would break environments where the system encoding is undefined, i.e. implicit string/unicode coercions are turned off. In such an environment, it is probably desirable that os.path.join performs no coercion as well, so this might need to get special-cased. Regards, Martin -- http://mail.python.org/mailman/listinfo/python-list
Re: How to write a ping client
Harlin Seritt [EMAIL PROTECTED] writes: ? #!/bin/sh ping $1 Enjoy, Nick -- # sigmask || 0.2 || 20030107 || public domain || feed this to a python print reduce(lambda x,y:x+chr(ord(y)-1),' Ojdl!Wbshjti!=obwAcboefstobudi/psh?') -- http://mail.python.org/mailman/listinfo/python-list
Need some Python help
Hello, I am new to Python and am trying to produce script to run batch processes for ArcGIS 9.0 (ArcView). I have upgraded to Phython 2.4 from 2.1 and am using the Pythonwin to try to code but am running into a problem. Whenever I try to debug my program or run any code past the following code it gets hung up and crashes, quits, no warning, and no messages. HELP, what is the problem, it is getting very frustrating. import win32com.client gp = win32com.client.Dispatch(esriGeoprocessing.GPDispatch.1) gp.workspace = c:/Program Files/ArcGIS/NASA It ALWAYS crashes and quits 30 sec or so after line 2 or 3 of the code above I can't get Python to do anything in ArcGIS so far, none of the tools can be called or used? I am assuming there is some sort of path or link that is not working properly between ArcGIS and Python? Using the same coding in the IDLE Python environment results in the same crashing results. Oh yea, I am running everything on Windows XP. Thank you. Matthew Upton -- http://mail.python.org/mailman/listinfo/python-list
Re: Dynamically pass a function arguments from a dict
Mark McEahern wrote: Dan Eloff wrote: How can you determine that func2 will only accept bar and zoo, but not foo and call the function with bar as an argument? Let Python answer the question for you: ... good explanation of how to do this for simple functions. Please be aware the normal way to do this is go ahead and call the function. Many function wrapping techniques will fail this test, and often the code that looks into the guts of a call in order to do something clever will fail when it is pointed at anything that uses the technique. Not only does curry: http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/52549 not show you what args it accepts, but decorators, a Python 2.4 invention, will typically obscure the interface of the decorated function. Since they wrap _any_ function call, they typically take the most general arguments possible in order to accommodate the widest range of functions to wrap. --Scott David Daniels [EMAIL PROTECTED] -- http://mail.python.org/mailman/listinfo/python-list
Dr. Dobb's Python-URL! - weekly Python news and links (Feb 24)
QOTW: Who's 'Guido'? -- Ilias Lazaridis
I know this document. It has no relevance to me. -- Ilias
Lazaridis, on URL: http://www.catb.org/~esr/faqs/smart-questions.html
Nobody asked them to do this (AFAIK), it's more that nobody could
_stop_ them from doing it. -- timbot, on the work of Jason Tishler
and Andrew MacIntyre with Cygwin and OS/2 EMX, respectively
Hot off the virtual press: Py2.4 Quick Reference:
http://groups-beta.google.com/group/comp.lang.python/browse_thread/thread/5be203da13eafdd2/
For a decade now, confident people have declaimed in
managers' meetings and conferences that {local,Web}
applications are {dead,utterly triumphant}, in all
combinations (and sometimes at the same venues) (and
sometimes by the same people!) (although not by the
same people at the same time). Real Programmers know
they need judgment and expertise on both sides. The
principal implications for Python: client-side Web
scripting is one of the few domains where Python is
*not* nearly ideal (although not for technical reasons);
but the best Weblications still can result from co-
operation between Python and other languages:
http://groups-beta.google.com/group/comp.lang.python/browse_thread/thread/b0085890efa29780/
Kartic and Tony Meyer provide nice two-minute tutorials
on imaplib, and, more generally, network programming:
http://groups-beta.google.com/group/comp.lang.python/browse_thread/thread/c8f87f28f00a9c93/
Tkinter has modal dialogues:
http://groups-beta.google.com/group/comp.lang.python/browse_thread/thread/8fce072f149f13c0/
Ron Stephens entertainingly advertises pyGoogle:
http://groups-beta.google.com/group/comp.lang.python/browse_thread/thread/e28557ad49b4619a/
Peaceful coexistence:
http://groups-beta.google.com/group/comp.lang.python/browse_thread/thread/3adfa3b1148aaa8e/
http://groups-beta.google.com/group/comp.lang.python/browse_thread/thread/3775e1b575d8fb67/
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
Mygale is a news-gathering webcrawler that specializes in (new)
World-Wide Web articles related to Python.
http://www.awaretek.com/nowak/mygale.html
While cosmetically similar, Mygale and the Daily Python-URL
are utterly different in their technologies and generally in
their results.
comp.lang.python.announce announces new Python software. Be
sure to scan this newsgroup weekly.
http://groups.google.com/groups?oi=djqas_ugroup=comp.lang.python.announce
Brett Cannon continues the marvelous tradition established by
Andrew Kuchling and Michael Hudson of intelligently summarizing
action on the python-dev mailing list once every other week.
http://www.python.org/dev/summary/
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/
The Python Business Forum further[s] the interests of companies
that base their business on ... Python.
http://www.python-in-business.org
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/donate.html
Kurt B. Kaiser publishes a weekly report on faults and patches.
http://www.google.com/groups?as_usubject=weekly%20python%20patch
Cetus collects Python hyperlinks.
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://aspn.activestate.com/ASPN/Cookbook/Python
Among several Python-oriented RSS/RDF feeds available are
http://www.python.org/channews.rdf
http://bootleg-rss.g-blog.net/pythonware_com_daily.pcgi
Python Modules for Various Internet Protocols?
Hello, I was wondering whether there are any Python modules for various Internet protocols, e.g., is there something similar to import ftp client = ftpopen(...) and so on. Thanks, Efrat -- http://mail.python.org/mailman/listinfo/python-list
Re: Python Modules for Various Internet Protocols?
Efrat Regev wrote: Hello, I was wondering whether there are any Python modules for various Internet protocols, e.g., is there something similar to Erfat...yes...batteries included! http://docs.python.org/lib/internet.html Thanks, -Kartic -- http://mail.python.org/mailman/listinfo/python-list
Re: Python Modules for Various Internet Protocols?
On Thu, Feb 24, 2005 at 11:11:07AM -0600, Efrat Regev wrote: I was wondering whether there are any Python modules for various Internet protocols, ... Twisted (http://twistedmatrix.com/products/twisted) is an event driven framework for writing network applications. It includes many internet protocols including ftp, irc, imap4, pop, etc... Chris -- http://mail.python.org/mailman/listinfo/python-list
Re: Python Modules for Various Internet Protocols?
Kartic [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] Efrat Regev wrote: Hello, I was wondering whether there are any Python Erfat...yes...batteries included! http://docs.python.org/lib/internet.html Thanks, -Kartic Excellent! more like generator included :-) Many thanks, Efrat -- http://mail.python.org/mailman/listinfo/python-list
Re: Font size
from random import randint rand = randint(0,36) print rand Don't forget about the double zero slot. Tobiah -- http://mail.python.org/mailman/listinfo/python-list
what is wrong?
I cannot find out why the following code generates the error:
(BTraceback (most recent call last):
(B File "D:/a/Utilities/python/ptyhon22/test.py", line 97, in ?
(Bmain()
(B File "D:/a/Utilities/python/ptyhon22/test.py", line 60, in main
(Bcrit = Critter(crit_name)
(B File "D:/a/Utilities/python/ptyhon22/test.py", line 8, in __init__
(Bself.feed = feed# I wrote this
(BAttributeError: can't set attribute
(B
(BI add some codes to a program on a book. The lines that have "I wrote
(Bthis" comment is the added codes. Could anyone tell me what is worng
(Bhere?
(B
(B--
(B##
(Bclass Critter(object):
(B"""A virtual pet"""
(Bdef __init__(self, name, hunger = 0, boredom = 0, feed = 0):
(Bself.name = name
(Bself.hunger = hunger
(Bself.boredom = boredom
(Bself.feed = feed# I wrote this
(B
(Bdef __pass_time(self):
(Bself.hunger += 1
(Bself.boredom += 1
(B
(Bdef __feed_time(self): # I worte this
(Bself.feed += 1 # I wote this
(B
(Bdef __get_feed(self): # I wrote this
(Breturn self.feed# I worte this
(B
(Bfeed = property(__get_feed) # I wrote this
(B
(Bdef __get_mood(self):
(Bunhappiness = self.hunger + self.boredom
(Bif unhappiness 5:
(Bmood = "happy"
(Belif 5 = unhappiness = 10:
(Bmood = "okay"
(Belif 11 = unhappiness = 15:
(Bmood = "frustrated"
(Belse:
(Bmood = "mad"
(Breturn mood
(B
(Bmood = property(__get_mood)
(B
(Bdef talk(self):
(Bprint "I'm", self.name, "and I feel", self.mood, "now.\n"
(Bself.__pass_time()
(B
(Bdef eat(self, food = 4):
(Bprint "Brruppp. Thank you."
(Bself.hunger -= food
(Bself.__feed_time() # I wrote this
(Bprint self.feed # I wrote this
(Bif self.hunger 0:
(Bself.hunger = 0
(Bself.__pass_time()
(B
(Bdef play(self, fun = 4):
(Bprint "Wheee!"
(Bself.boredom -= fun
(Bif self.boredom 0:
(Bself.boredom = 0
(Bself.__pass_time()
(B
(B##
(B
(Bdef main():
(Bcrit_name = raw_input("What do you want to name your critter?: ")
(Bcrit = Critter(crit_name)
(B
(Bchoice = None
(Bwhile choice != "0":
(Bprint \
(B"""
(BCritter Caretaker
(B
(B0 - Quit
(B1 - Listen to your critter
(B2 - Feed your critter
(B3 - Play with your critter
(B"""
(B
(Bchoice = raw_input("Choice: ")
(Bprint
(B
(B# exit
(Bif choice == "0":
(Bprint "Good-bye."
(B
(B# listen to your critter
(Belif choice == "1":
(Bcrit.talk()
(B
(B# feed your critter
(Belif choice == "2":
(Bcrit.eat()
(B
(B# play with your critter
(Belif choice == "3":
(Bcrit.play()
(B
(B# some unknown choice
(Belse:
(Bprint "\nSorry, but", choice, "isn't a valid choice."
(B
(Bmain()
(B("\n\nPress the enter key to exit.")
(B
(B--
(Bhttp://mail.python.org/mailman/listinfo/python-list
Re: duplicate file finder (was: how can I make this script shorter?)
On Wed, 23 Feb 2005 01:56:02 -0800, rumours say that Lowell Kirsh
[EMAIL PROTECTED] might have written:
Good idea about hashing part of the file before comparing entire files.
It will make the script longer but the speed increase will most likely
make it worth it.
My dupefind module was one of the first modules I wrote in python (it was a
shell script once...), so it's not appropriate to post. However, rewriting it
was in my RSN list; after your post, I said, what the heck :)
I wouldn't describe it as /clean/ Python code, so any comments on style,
methodology (and of course, bugs!) are mostly welcome. If you have any ideas
how to make it more Pythonic in style, perhaps we can even send it to ASPN.
On the upside, it's a good demo of Python dynamism and therefore power.
All first spaces are converted to pipe symbols to keep code indents, and sorry
for the assignment operators lacking spacing at the left, but it helped me know
what I meant in C, so I kept the habit in Python.
dupefinder.py -- a module to find duplicate files.
find_duplicate_files(*paths):
. A function returning an iterable of lists of duplicate files
. To be used as
. for duplicate_files in dupefinder.find_duplicate_files(dir1, dir2...):
. # process every group of duplicates
import os, md5, errno, sys
IGNORED_ERROR_CODES= frozenset( [errno.EACCES, errno.ENOENT] )
class File(object):
. A wrapper for files to facilitate their comparison.
.
. Interface:
. - .get_hash(level) returns appropriate key for the current cmp level
. - .filename
. - .size
. __slots__= filename, size, _hashes,
. def __init__(self, filename):
. self.filename= filename
. self.size= os.path.getsize(filename)
. if self.size == 0:
. self._hashes= [0, None, None]
. else:
. self._hashes= [self.size]
. def __repr__(self):
. return %s('%s') % (self.__class__.__name__, self.filename)
. def get_hash(self, level):
. Return appropriate key for level of comparison.
. level == 0 returns file size
. level == 1 returns hash of first few kb
. level == 2 returns md5 sum of whole file
. if level = len(self._hashes):
. if 1 = len(self._hashes):
. self._hashes.append(self._get_partial_hash())
. if 2 = len(self._hashes):
. self._hashes.append(self._get_full_hash())
. return self._hashes[level]
. def _get_partial_hash(self):
. fp= open(self.filename)
. try:
. return hash(fp.read(8192))
. finally:
. fp.close()
. def _get_full_hash(self):
. fp= open(self.filename, rb)
. full_hash= md5.new()
. while 1:
. data= fp.read(65536)
. if not data: break
. full_hash.update(data)
. fp.close()
. return full_hash.digest()
class GenericFilesDict(dict):
. A virtual wrapper for the dictionaries of file comparisons.
. Not to be used on its own, but through subclassing.
.
. Each subclass should define a _level class attribute to be used with the
. File.get_hash method, and a _next_class attribute pointing to the class
. managing the next level comparisons.
. __slots__= ()
. def add_file(self, fileobj):
. Add a File object to self keyed by the appropriate key based on
. self._level. If another file object exists in the same spot, replace it
. by a _next_level_class instance containing the pre-existing and new file
. obj.
. this_hash= fileobj.get_hash(self._level)
. try:
. result = self[this_hash]
. except KeyError:
. self[this_hash]= fileobj
. return
. try: # there was something in slot [this_hash]
. result.add_file(fileobj) # so add fileobj to it
. except AttributeError: # it has no add_file method, so it's a File
. _= self[this_hash]= self._next_class() # make an instance
. _.add_file(result) # add pre-existing
. _.add_file(fileobj) # add new
. def __repr__(self):
. return %s%s % (self.__class__.__name__, dict.__repr__(self))
. def __iter__(self):
. Return all instances of SameFiles (subclass of list).
. for item, value in self.iteritems():
. try: _next_class= value._next_class
. except AttributeError: continue
. if _next_class is None:
. yield value
. else:
. for item in value:
. yield item
class SameFiles(list):
. A list of duplicate files.
. __slots__= ()
. _level= 3
. _next_class= None # search stops here
. def add_file(self, fileobj):
. self.append(fileobj)
class FilesByFullHash(GenericFilesDict):
. A dictionary keyed on md5 hash of whole file.
. The algorithm assures that all File objects in this dict
. have the same size and the same hash of first few kiB.
. __slots__= ()
. _level= 2
. _next_class= SameFiles
class
Re: what is wrong?
[EMAIL PROTECTED] wrote: (B(...) (B self.feed = feed# I wrote this (B AttributeError: can't set attribute (B (B I add some codes to a program on a book. The lines that have "I wrote (B this" comment is the added codes. Could anyone tell me what is worng (B here? (B (Bthe line: (B (Bfeed = property(__get_feed) # I wrote this (B (Bmakes "feed" a *readonly* attribute. (B (Bcheers, (Bdeelan. (B (B-- (B@prefix foaf: http://xmlns.com/foaf/0.1/ . (B#me a foaf:Person ; foaf:nick "deelan" ; (Bfoaf:weblog http://blog.deelan.com/ . (B-- (Bhttp://mail.python.org/mailman/listinfo/python-list
Re: Canonical way of dealing with null-separated lines?
On Wed, Feb 23, 2005 at 10:54:50PM -0500, Douglas Alan wrote:
Is there a canonical way of iterating over the lines of a file that
are null-separated rather than newline-separated?
I'm not sure if there is a canonical method, but I would recommending using a
generator to get something like this, where 'f' is a file object:
def readnullsep(f):
# Need a place to put potential pieces of a null separated string
# across buffer boundaries
retain = []
while True:
instr = f.read(2048)
if len(instr)==0:
# End of file
break
# Split over nulls
splitstr = instr.split('\0')
# Combine with anything left over from previous read
retain.append(splitstr[0])
splitstr[0] = ''.join(retain)
# Keep last piece for next loop and yield the rest
retain = [splitstr[-1]]
for element in splitstr[:-1]:
yield element
# yield anything left over
yield retain[0]
Chris
--
http://mail.python.org/mailman/listinfo/python-list
Re: what is wrong?
On 24 Feb 2005 08:34:09 -0800, rumours say that [EMAIL PROTECTED] might have written: I cannot find out why the following code generates the error: Traceback (most recent call last): File D:/a/Utilities/python/ptyhon22/test.py, line 97, in ? main() File D:/a/Utilities/python/ptyhon22/test.py, line 60, in main crit = Critter(crit_name) File D:/a/Utilities/python/ptyhon22/test.py, line 8, in __init__ self.feed = feed# I wrote this AttributeError: can't set attribute I add some codes to a program on a book. The lines that have I wrote this comment is the added codes. Could anyone tell me what is worng here? [snip] class Critter(object): This fails as you said: self.feed = feed# I wrote this [snip] And this would fail: def __feed_time(self): # I worte this self.feed += 1 # I wote this Because of this: feed = property(__get_feed) # I wrote this which specifies only a 'get' method for the property. [snip] feed is a property, and there is not 'set' method for it, so it's behaving as read-only. Search for 'property' in your python docs. -- TZOTZIOY, I speak England very best. Be strict when sending and tolerant when receiving. (from RFC1958) I really should keep that in mind when talking with people, actually... -- http://mail.python.org/mailman/listinfo/python-list
Re: Canonical way of dealing with null-separated lines?
Douglas Alan wrote: Is there a canonical way of iterating over the lines of a file that are null-separated rather than newline-separated? Sure, I can implement my own iterator using read() and split(), etc., but considering that using find -print0 is so common, it seems like there should be a more cannonical way. You could start with this code and add '\0' as a line terminator: http://members.dsl-only.net/~daniels/ilines.html --Scott David Daniels [EMAIL PROTECTED] -- http://mail.python.org/mailman/listinfo/python-list
Re: Selective HTML doc generation
Graham Ashton said unto the world upon 2005-02-24 04:54: Thanks Brian, much appreciated. Looks quite straightforward. Graham Hi Graham, glad it helped -- I think this marks the first time I've given a useful answer to a non-trivial question on comp.lang.python. :-) context for future thread readers G: Hi. I'm looking for a documentation generation tool (such as pydoc, epydoc, happydoc, etc.) that will allow me to filter what it includes in it's output. I only want the reader to know about classes and methods in my package if if the classes have docstrings. B: Pointed Graham to to the visiblename function of pydoc.py, where I recently made a small change to get it to display `private' methods, and hypothesized that would be where he'd want to start in order to modify pydoc to meet his needs. /context for future thread readers Before I responded, I tried for a bit to write the code to filter for only those objects with docstrings like you wanted. I'm fairly new to programming and wasn't able to work out exactly what code is needed. (My skill level is such that it isn't quite so straight-forward to me :-) Would you be willing to post what you did to make it work? I think I'd learn something, having bounced off when making a (gentle) push on the problem. Best, Brian vdB -- http://mail.python.org/mailman/listinfo/python-list
Re: Vectors in Visual Python
Thanks for all your help everyone, if only it had addressed what I had asked I may have actually learned something about Python!! If anything was addressed to my problem then it has completely passed me by as most points were clearly made by a computer scientist and I am not one of those in the slightest. My experience of using any type of programming language is limited to the little we are taught in my non-computing subject and hence I have no idea what the below is all about!! In future example code may be more useful to help newbies like me :) That ``speciufication'' (sic) is no more ``a declaration'' than any other parameter you can pass to a constructor (or any other factory callable). -- http://mail.python.org/mailman/listinfo/python-list
Re: arrow keys bug
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi there, On Feb 24, 2005, at 16:25, A.T. Hofkamp wrote: and for home, end, etc. Does anyone here knows how I can strip those keys? Thanks in advance. One solution is to read the input yourself character by character, and delete anything that is not printable. Another solution may be to prevent sending non-ASCII to the server, ie check such things after enter is pressed. Thanks for your quick answer, however I'm not sure how I can do any of those things. I would appreciate if you could tell me how to do that, give-me a link to a how-to about that or the location of that in the python-docs, as I can't seem to find anything about that. Thanks in advance. - -- Best Regards, Daniel Alexandre ( [EMAIL PROTECTED] ) PGP Public Key: http://student.dei.uc.pt/~dfcruz/pubring.html -BEGIN PGP SIGNATURE- Version: GnuPG v1.2.4 (Darwin) iD8DBQFCHgw3L3+DjgQV3LgRAuoUAJ4rxaQ2Ll/Z4Jge4cakpqmIwWtRuACfd/l7 Gc+P1TlZxPJFh0qhKWCerOo= =j+Yb -END PGP SIGNATURE- -- http://mail.python.org/mailman/listinfo/python-list
update images inside a mysql database
hello,
i develop a project with a mysql interface. one mysql table holds all
the images for my project.
everything works quite well so far, except i'm not able to upload images
into the database. the following function does the mysql UPDATE, it
requires the image and the image ID as arguments.
additionally it dumps the image to my filesystem ('/tmp/image.gif') -
i test this with gif images.
for some reason, the file dumped to /tmp/image.gif is exactly the same
as uploaded, but in mysql the file is corrupted, far to small and not
even viewable.
here is my function:
def i_update(image, imgid):
image = %s % (image)
sql_exec = UPDATE Images SET Image='%s' WHERE ImgID = '%s'
% (image, imgid)
o = open(/tmp/file.jpg, w)
o.write(image)
o.close()
db_connect.cursor.execute(sql_exec)
i've the strong feeling that the substitution makes problems. if the
string 'image' conains ' or for example, the sql_exec is broken.
what do you suggest?
bye
jonas
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Re: what is wrong?
I appreciate all of your help. I learned a lot form your adovice. Thanks. Mr. Bieber, it worked fine. Thanks again. -- http://mail.python.org/mailman/listinfo/python-list
Re: Shift Confusion
Dennis Lee Bieber [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] On 23 Feb 2005 22:06:54 -0800, Kamilche [EMAIL PROTECTED] declaimed the following in comp.lang.python: Essentially, it should be possible to use a 'packed string' format in Python, where as long as the characters you're sending are in the ASCII range 0 to 127, two will fit in a byte. Pardon? You are going to fit TWO 7-bit values into one 8-bit? Quite. Although you can sort of see how one might naively arrive at this conclusion: one 7-bit char takes 0...127, which when you put it into an 8-bit byte leaves 128...255 unused for a second char James -- http://mail.python.org/mailman/listinfo/python-list
Re: Need some Python help
There's a bug in python's tokenizer that's triggered when the generated wrapper code for a COM object has lines longer than 512. See below link for a workaround: https://sourceforge.net/tracker/?func=detailatid=551954aid=1085454group_id=78018 Roger Matt Upton [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] Hello, I am new to Python and am trying to produce script to run batch processes for ArcGIS 9.0 (ArcView). I have upgraded to Phython 2.4 from 2.1 and am using the Pythonwin to try to code but am running into a problem. Whenever I try to debug my program or run any code past the following code it gets hung up and crashes, quits, no warning, and no messages. HELP, what is the problem, it is getting very frustrating. import win32com.client gp = win32com.client.Dispatch(esriGeoprocessing.GPDispatch.1) gp.workspace = c:/Program Files/ArcGIS/NASA It ALWAYS crashes and quits 30 sec or so after line 2 or 3 of the code above I can't get Python to do anything in ArcGIS so far, none of the tools can be called or used? I am assuming there is some sort of path or link that is not working properly between ArcGIS and Python? Using the same coding in the IDLE Python environment results in the same crashing results. Oh yea, I am running everything on Windows XP. Thank you. Matthew Upton == Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News== http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups = East and West-Coast Server Farms - Total Privacy via Encryption = -- http://mail.python.org/mailman/listinfo/python-list
Re: update images inside a mysql database
Jonas Meurer wrote: def i_update(image, imgid): image = %s % (image) sql_exec = UPDATE Images SET Image='%s' WHERE ImgID = '%s' % (image, imgid) o = open(/tmp/file.jpg, w) o.write(image) o.close() db_connect.cursor.execute(sql_exec) I've never tried extensively to use images inside a database (too slow for most of my uses), but I thought I'd drop in to point out that you should, for security reasons, be using place holders on your sql. It might just fix your image problem as well, but I don't know. Also, converting a binary image into a string doesn't seem like it would be wise, but like I said, I've never tried it. At any rate, your function would look like this: def i_update(image, imgid): image = %s % (image) o = open(/tmp/file.jpg, w) o.write(image) o.close() db_connect.cursor.execute(UPDATE Images SET Image=%s WHERE ImgID=%s, (image, imgid)) -- http://mail.python.org/mailman/listinfo/python-list
Re: Trouble with mysql-python 1.2.0 on Solaris 8 sparc
Alec Wysoker wrote: Hi Andy, Thanks for your message. It turned out that I had installed 64-bit mySql on a 32-bit machine. I'm amazed it worked at all. Anyway, I finally got mysql-python built, but I'm unable to connect to a machine on a remote host. The problem doesn't seem to be with the python code, because I'm unable to do it even with the mysql command-line client. Sigh. Could be you have a 4.2 server and an earlier client. Unbelievably, MySQL changed its protocol while only incrementing the minor version number, and this bit me in the ass when I wanted to move up to 4.1. regards Steve -- http://mail.python.org/mailman/listinfo/python-list
[ANN] dateutil 0.9
https://moin.conectiva.com.br/DateUtil Description --- The dateutil module provides powerful extensions to the standard datetime module, available in Python 2.3+. Features - Computing of relative deltas (next month, next year, next monday, last week of month, etc); - Computing of relative deltas between two given date and/or datetime objects; - Computing of dates based on very flexible recurrence rules, using a superset of the iCalendar specification. Parsing of RFC strings is supported as well. - Generic parsing of dates in almost any string format; - Timezone (tzinfo) implementations for tzfile(5) format files (/etc/localtime, /usr/share/zoneinfo, etc), TZ environment string (in all known formats), iCalendar format files, given ranges (with help from relative deltas), local machine timezone, fixed offset timezone, UTC timezone, and Windows registry-based time zones. - Internal up-to-date world timezone information based on Olson's database. - Computing of Easter Sunday dates for any given year, using Western, Orthodox or Julian algorithms; - More than 400 test cases. Version 0.9 --- - Implemented internal timezone information with binary timezone files [1]. datautil.tz.gettz() function will now try to use the system timezone files, and fallback to the internal versions. It's also possible to ask for the internal versions directly by using dateutil.zoneinfo.gettz(). - New tzwin timezone type, allowing access to Windows internal timezones (contributed by Jeffrey Harris). - Fixed parsing of unicode date strings. - Fixed pickling of timezone types, as reported by Andreas Köhler. - Accept parserinfo instances as the parser constructor parameter, besides parserinfo (sub)classes. - Changed weekday to spell the not-set n value as None instead of 0. - Fixed other reported bugs. [1] http://www.twinsun.com/tz/tz-link.htm -- Gustavo Niemeyer http://niemeyer.net -- http://mail.python.org/mailman/listinfo/python-list
Mapping operator tokens to special methods
I was starting to write a dictionary to map operator strings to their
equivalent special methods such as:
{
'+' : 'add',
'' : 'and_'
}
The idea is to build a simple interactive calculator.
and was wondering if there is already something like this builtin?
Or is there a better way to do what I want?
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[ANN] TamTam collaboration software
Hi, on address (temporary): http://tamtam.mi2.hr:/NoviTam/ you can find TamTam collaborative software. This is new version (rewrite) using Twisted and Nevow. This is not official announcement just a small notice for people who are interested to check it, give me some critics, help in ideas or maybe help in development. Aco -- http://aco.mi2.hr/ -- http://mail.python.org/mailman/listinfo/python-list
Interesting decorator use.
I have started doing the following to watch for exceptions in wxPython. I'd like any input about (A) the interface, and (B) the frame before I throw it in the recipes book. import wx, os, sys errorframe = None def watcherrors(function): '''function decorator to display Exception information.''' def substitute(*args, **kwargs): try: return function(*args, **kwargs) except Exception: error_type, error, traceback = sys.exc_info() mb = wx.MessageDialog(errorframe, '%s\n\nClick OK to see traceback' % error, 'Error in Run', wx.OK | wx.CANCEL | wx.ICON_ERROR) if wx.ID_OK == mb.ShowModal(): mb.Destroy() from traceback import extract_tb trace = ['%s line %s in %s:\n\t%s' % ( (os.path.splitext(os.path.split( name)[1])[0], line, fun, text) for name, line, fun, text in extract_tb(traceback)] mb = wx.MessageDialog(errorframe, '\n'.join(['%s\n' % error] + trace), 'Run Error w/ Traceback', wx.OK | wx.ICON_ERROR) result = mb.ShowModal() mb.Destroy() raise if function.__doc__ is not None: substitute.__doc__ = function.__doc__ return substitute You can use it as follows to wrap functions and methods: @watcherrors def something(somearg) if somearg is not None: raise ValueError(somearg) You can use this by simply placing '@watcherrors' on the line before a function or method definition. Some of my questions are: A) Is there a better name? Perhaps exceptions or watcher? B) Is a global the right way to define the parent of the driven message box, or adding another wrapper layer as follows better? def exceptionwatcher(base, name): def watcherrors( ... def substitute(*args, **kwargs): try: return function(*args, **kwargs) except Exception: error_type, error, traceback = sys.exc_info() errorframe = getattr(base, name, None) ### new code ... return watcherrors Wrapping the code this way allows you to say, watcher-by-watcher, where to get the parent for the message box. You would then use it as follows: @exceptionwatcher(someholder, 'frame') def something(somearg) if somearg is not None: raise ValueError(somearg) C) Stuff I've not even thought of. --Scott David Daniels [EMAIL PROTECTED] -- http://mail.python.org/mailman/listinfo/python-list
Re: Mapping operator tokens to special methods
[EMAIL PROTECTED] wrote:
I was starting to write a dictionary to map operator strings to their
equivalent special methods such as:
{
'+' : 'add',
'' : 'and_'
}
The idea is to build a simple interactive calculator.
and was wondering if there is already something like this builtin?
Or is there a better way to do what I want?
There's not already a mapping builtin, but you should definitely look at
the operator module:
py import operator
py ops = {'+':operator.add, '':operator.and_}
py ops['+'](3, 2)
5
py ops[''](3, 2)
2
STeVe
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Re: Canonical way of dealing with null-separated lines?
Douglas Alan wrote: ... In any case, as a suggestion to the whomever it is that arranges for stuff to be put into the standard library, there should be something like this there, so everyone doesn't have to reinvent the wheel (even if it's an easy wheel to reinvent) for something that any sysadmin (and many other users) would want to do on practically a daily basis. The general model is that you produce a module, and if it gains a audience to a stable interface, inclusion might be considered. I'd suggest you put up a recipe at ActiveState. --Scott David Daniels [EMAIL PROTECTED] -- http://mail.python.org/mailman/listinfo/python-list
Re: Canonical way of dealing with null-separated lines?
On Thu, Feb 24, 2005 at 02:03:52PM -0500, Douglas Alan wrote: Thanks for the generator. It returns an extra blank line at the end when used with find -print0, which is probably not ideal, and is also not how the normal file line iterator behaves. But don't worry -- I can fix it. Sorry... I forgot to try it with a null terminated string. I guess it further illustrates the power of writing good test cases. Something like this would help: # yield anything left over if retain[0]: yield retain[0] The other modification would be an option to ignore multiple nulls in a row, rather than returning empty strings, which could be done in a similar way. Chris -- http://mail.python.org/mailman/listinfo/python-list
Re: Shift Confusion
Dennis Lee Bieber wrote: On Thu, 24 Feb 2005 14:22:59 -, Richard Brodie [EMAIL PROTECTED] declaimed the following in comp.lang.python: John Machin [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] Essentially, it should be possible to use a 'packed string' format in Python, where as long as the characters you're sending are in the ASCII range 0 to 127, two will fit in a byte. It should be possible, but only in a realm where phlogiston and perpetual motion machines exist. alt.sys.pdp10 ? Closest thing I know of to what is being attempted is DEC's RAD-50; but that was essentially just uppercase A..Z, 0..9, and a few punctuation marks, and packed three of them into two bytes. Another code it used was known as SIXBIT, allowing 64 different characters. IIRC it could cope with letters, digits and a bunch of punctuation - see http://nemesis.lonestar.org/reference/telecom/codes/sixbit.html The DECSystem-10 used a 3-6 bit word, so you could get six sixbit characters to a word. In ASCII you could only get four (or, if you threw the parity bit away, five) characters to a word. While its character-handling instructions weren't, as I recall, unique in the industry, the DECSystem-10 remains the only hardware I ever got to use that had instructions to handle variable byte sizes. regards Steve -- http://mail.python.org/mailman/listinfo/python-list
Re: Trouble with mysql-python 1.2.0 on Solaris 8 sparc
Alec Wysoker wrote: Hi Steve, Thanks for the response. I don't think this is the problem. When I connect to the remote machine, it says this: Your MySQL connection id is 58 to server version: 4.1.0-alpha-standard When I connect to the local server, I get this: Your MySQL connection id is 6 to server version: 4.1.10-standard One would assume that 4.1.0 and 4.1.10 are compatible, no? Indeed. Sorry I couldn't be of more assistance. I suspected that the MySQLdb driver was somehow compiled with 4.0-or-earlier client software - is this possible? regards Steve -- Steve Holden+1 703 861 4237 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ Python Web Programming http://pydish.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Trouble with mysql-python 1.2.0 on Solaris 8 sparc
Do you mean the python glue code? I am having this problem when python is not in the picture at all, just running mysql command-line client. Presumably my client is 4.1.10, as it came in a built package along with the 4.1.10 server. In fact, the following seems to indicate that it is the right version: /usr/local/mysql/bin/mysql --version /usr/local/mysql/bin/mysql Ver 14.7 Distrib 4.1.10, for sun-solaris2.8 (sparc) At 03:08 PM 2/24/2005, Steve Holden wrote: Alec Wysoker wrote: Hi Steve, Thanks for the response. I don't think this is the problem. When I connect to the remote machine, it says this: Your MySQL connection id is 58 to server version: 4.1.0-alpha-standard When I connect to the local server, I get this: Your MySQL connection id is 6 to server version: 4.1.10-standard One would assume that 4.1.0 and 4.1.10 are compatible, no? Indeed. Sorry I couldn't be of more assistance. I suspected that the MySQLdb driver was somehow compiled with 4.0-or-earlier client software - is this possible? regards Steve -- Steve Holden+1 703 861 4237 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ Python Web Programming http://pydish.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Interesting decorator use.
On Thu, 24 Feb 2005 11:15:07 -0800, Scott David Daniels [EMAIL PROTECTED] wrote: I have started doing the following to watch for exceptions in wxPython. I'd like any input about (A) the interface, and (B) the frame before I throw it in the recipes book. import wx, os, sys errorframe = None def watcherrors(function): '''function decorator to display Exception information.''' def substitute(*args, **kwargs): ... Pretty cool. Question on decorators in general. Can you parameterize those? If I wanted to something and after the function call for example, I would expect something like this would work. def prepostdecorator(function,pre,post): def wrapper(*args,**kwargs): pre() result = function(*args,**kwargs) post() return result return wrapper def dopre(): print call pre def dopost(): print call post @prepostdecorator(pre,post) def sayhello(Name): print Hey %s, nice to meet you % Name #sayhello = prepostdecorator(sayhello,dopre,dopost) if __name__==__main__: sayhello(Dude) but I get ... TypeError: prepostdecorator() takes exactly 3 arguments (2 given) Where as def prepostdecorator(function,pre,post): def wrapper(*args,**kwargs): pre() result = function(*args,**kwargs) post() return result return wrapper def dopre(): print call pre def dopost(): print call post def sayhello(Name): print Hey %s, nice to meet you % Name sayhello = prepostdecorator(sayhello,dopre,dopost) if __name__==__main__: sayhello(Dude) #outputs call pre Hey Dude, nice to meet you call post Does what I want. I guess I'm having problems with how function get's in there similair to how self magically gets in a method, except when you specify other params. Got linky? -- Thomas G. Willis http://paperbackmusic.net -- http://mail.python.org/mailman/listinfo/python-list
Re: Canonical way of dealing with null-separated lines?
On Thu, 24 Feb 2005 11:53:32 -0500, Christopher De Vries
[EMAIL PROTECTED] wrote:
On Wed, Feb 23, 2005 at 10:54:50PM -0500, Douglas Alan wrote:
Is there a canonical way of iterating over the lines of a file that
are null-separated rather than newline-separated?
I'm not sure if there is a canonical method, but I would recommending using a
generator to get something like this, where 'f' is a file object:
def readnullsep(f):
# Need a place to put potential pieces of a null separated string
# across buffer boundaries
retain = []
while True:
instr = f.read(2048)
if len(instr)==0:
# End of file
break
# Split over nulls
splitstr = instr.split('\0')
# Combine with anything left over from previous read
retain.append(splitstr[0])
splitstr[0] = ''.join(retain)
# Keep last piece for next loop and yield the rest
retain = [splitstr[-1]]
for element in splitstr[:-1]:
(1) Inefficient (copies all but the last element of splitstr)
yield element
# yield anything left over
yield retain[0]
(2) Dies when the input file is empty.
(3) As noted by the OP, can return a spurious empty line at the end.
Try this:
!def readweird(f, line_end='\0', bufsiz=8192):
!retain = ''
!while True:
!instr = f.read(bufsiz)
!if not instr:
!# End of file
!break
!splitstr = instr.split(line_end)
!if splitstr[-1]:
!# last piece not terminated
!if retain:
!splitstr[0] = retain + splitstr[0]
!retain = splitstr.pop()
!else:
!if retain:
!splitstr[0] = retain + splitstr[0]
!retain = ''
!del splitstr[-1]
!for element in splitstr:
!yield element
!if retain:
!yield retain
Cheers,
John
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Re: Mapping operator tokens to special methods
On 24 Feb 2005 10:57:58 -0800, [EMAIL PROTECTED] wrote:
I was starting to write a dictionary to map operator strings to their
equivalent special methods such as:
{
'+' : 'add',
'' : 'and_'
}
The idea is to build a simple interactive calculator.
and was wondering if there is already something like this builtin?
eval('1+2')
3
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More newbie macosx user questions
I think I'm mis-understanding something about how PYTHONPATH works (at least on OSX I didn't have this trouble on Linux). I have a directory where I store libraries that I'm playing around with. However, for some reason python can't find the library. Since I'm using PyQt, I use pythonw, but the results are identical with python. It doesn't look like my PYTHONPATH is getting prepended to the library path. Can anyone tell me what I'm doing wrong? ([EMAIL PROTECTED]) echo $PYTHONPATH /Users/timothygrant/code/lib ([EMAIL PROTECTED]) ls $PYTHONPATH NJB.pyNJB.pyc _njb_c.so njb_c.py njb_c.pyc ([EMAIL PROTECTED]) pythonw Python 2.3 (#1, Sep 13 2003, 00:49:11) [GCC 3.3 20030304 (Apple Computer, Inc. build 1495)] on darwin Type help, copyright, credits or license for more information. import NJB Traceback (most recent call last): File stdin, line 1, in ? ImportError: No module named NJB import sys for p in sys.path: ... print p ... /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python23.zip /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3 /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3/plat-darwin /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3/plat-mac /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3/plat-mac/lib-scriptpackages /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3/lib-tk /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3/lib-dynload /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3/site-packages -- http://mail.python.org/mailman/listinfo/python-list
Re: Mapping operator tokens to special methods
John Machin wrote:
eval('1+2')
3
--
Yeah, that's what I decided to do.
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Re: Python and Ajax technology collaboration
Does anyone else have any Nevow examples? In article [EMAIL PROTECTED], [EMAIL PROTECTED] says... aurora [EMAIL PROTECTED] wrote: It was discussed in the last Bay Area Python Interest Group meeting. Thursday, February 10, 2005 Agenda: Developing Responsive GUI Applications Using HTML and HTTP Speakers: Donovan Preston http://www.baypiggies.net/ The author has a component LivePage for this. You may find it from http://nevow.com/. Similar idea from the Javascript stuff but very Python centric. As an example for that technology (LivePage) I have this: http://vercingetorix.dyndns.org:20080/ Which is an online forum where the Quote Reply function is done with XMLHttpRequest and Python. Implementing this stuff in the forum with Nevow ( the framework created by Donovan who I help to develop ) was almost effortless. -- http://mail.python.org/mailman/listinfo/python-list
Re: [perl-python] exercise: partition a list by equivalence
A slightly better version, only walks the set of cumulative list of sets once per pairing. -- Paul .import sets . .input = [[1, 2], [3, 4], [2, 3], [4, 5]] .input = [[1, 2], [3, 4], [4, 5]] .input = [[1, 2],[2,1], [3, 4], [4, 5],[2,2],[2,3],[6,6]] . .def merge(pairings): .ret = [] .for a,b in pairings: .aset = None .bset = None .for s in ret: .if not aset and a in s: .aset = s .if not bset and b in s: .bset = s .if aset and bset: .break .else: .if aset: .aset.add(b) .elif bset: .bset.add(a) .else: .ret.append(sets.Set([a,b])) .continue .if aset is not bset: .ret.remove(aset) .ret.remove(bset) .ret.append(aset.union(bset)) . .return [list(s) for s in ret] . .print merge(input) -- http://mail.python.org/mailman/listinfo/python-list
Re: Interesting decorator use.
Tom Willis wrote:
Question on decorators in general. Can you parameterize those?
If I wanted to something and after the function call for example, I
would expect something like this would work.
def prepostdecorator(function,pre,post):
def wrapper(*args,**kwargs):
pre()
result = function(*args,**kwargs)
post()
return result
return wrapper
def dopre():
print call pre
def dopost():
print call post
@prepostdecorator(pre,post)
def sayhello(Name):
print Hey %s, nice to meet you % Name
#sayhello = prepostdecorator(sayhello,dopre,dopost)
if __name__==__main__:
sayhello(Dude)
but I get ...
TypeError: prepostdecorator() takes exactly 3 arguments (2 given)
You get this TypeError for the same reason that I get the following
TypeError:
py def prepostdecorator(function, pre, post):
... pass
...
py prepostdecorator(1, 2)
Traceback (most recent call last):
File interactive input, line 1, in ?
TypeError: prepostdecorator() takes exactly 3 arguments (2 given)
The expression after @ is a _normal Python expression_. So since you
couldn't call prepostdecorator with 2 arguments in any other situation,
you still can't.
If you want to call prepostdecorator with 2 arguments, you need to write
it this way. A few options:
(1) Use nested functions:
py def prepostdecorator(pre,post):
... def decorator(function):
... def wrapper(*args,**kwargs):
... pre()
... result = function(*args,**kwargs)
... post()
... return result
... return wrapper
... return decorator
...
py @prepostdecorator(dopre, dopost)
... def sayhello(name):
... print Hey %s, nice to meet you % name
...
py sayhello('Tom')
call pre
Hey Tom, nice to meet you
call post
(2) Use functional.partial (PEP 309[1])
py def prepostdecorator(pre, post, function):
... def wrapper(*args,**kwargs):
... pre()
... result = function(*args,**kwargs)
... post()
... return result
... return wrapper
...
py @partial(prepostdecorator, dopre, dopost)
... def sayhello(name):
... print Hey %s, nice to meet you % name
...
py sayhello('Tom')
call pre
Hey Tom, nice to meet you
call post
(3) Use a class:
py class prepostdecorator(object):
... def __init__(self, pre, post):
... self.pre, self.post = pre, post
... def __call__(self, function):
... def wrapper(*args,**kwargs):
... self.pre()
... result = self.function(*args,**kwargs)
... self.post()
... return result
... return wrapper
py @prepostdecorator(dopre, dopost)
... def sayhello(name):
... print Hey %s, nice to meet you % name
...
py sayhello('Tom')
call pre
Hey Tom, nice to meet you
call post
Note that in all of the above cases, the result of evaluating the
expression after the @ is a callable object that takes _exactly one_
argument, the function to be decorated.
HTH,
STeVe
[1] http://www.python.org/peps/pep-0309.html
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Re: Interesting decorator use.
I wrote:
Tom Willis wrote:
Question on decorators in general. Can you parameterize those?
[snip]
If you want to call prepostdecorator with 2 arguments, you need to write
it this way. A few options:
Sorry, I forgot my favorite one:
(4) Use a class and functional.partial:
py class prepostdecorator(object):
... def __init__(self, pre, post, function):
... self.pre, self.post, self.function = pre, post, function
... def __call__(self, *args, **kwargs):
... self.pre()
... result = self.function(*args,**kwargs)
... self.post()
... return result
...
py @partial(prepostdecorator, dopre, dopost)
... def sayhello(name):
... print Hey %s, nice to meet you % name
...
py sayhello('Tom')
call pre
Hey Tom, nice to meet you
call post
Woo-hoo, I got rid of all the nested functions! ;)
STeVe
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Re: update images inside a mysql database
On 24/02/2005 Gabriel Cooper wrote: I've never tried extensively to use images inside a database (too slow for most of my uses), but I thought I'd drop in to point out that you should, for security reasons, be using place holders on your sql. It might just fix your image problem as well, but I don't know. i don't know what your example changes with using placeholders, as my version used placeholders as well. anyway, i changed my code to resemble your version. i still get the same problem: (cgitb output) ---SNIP- /home/jonas/public_html/inventaria/mods/backend.py in i_update(image='\xff\xd8\xff\xe0\x00\x10JFIF\x00\x01\x01\x01\x00\x00\x00\x00\x00\x00\xff\xdb\x00C\x00\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01...#$\x82\x08f\xe5A\xc6\xe2G\xe4I\xa9\x18\x96.\xa7\x18T\x0e\x08\xe0\x92q\x9c\x9e\xa4s\xd3\xb7j(\xa0\n\xa4\x95\x00\x03\xdd\x87\xafC\ xefE\x14P\x07\xff\xd9', imgid='18') 259 o.write(image) 260 o.close() 261 db_connect.cursor.execute(UPDATE Images SET Image=%s WHERE 262 ImgID = %s % (image, imgid)) 263 global db_connect = module 'db_connect' from 'mods/db_connect.pyc', db_connect.cursor = MySQLdb.cursors.Cursor object, db_connect.cursor.execute = bound method Cursor.execute of MySQLdb.cursors.Cursor object, image = '\xff\xd8\xff\xe0\x00\x10JFIF\x00\x01\x01\x01\x00\x00\x00\x00\x00\x00\xff\xdb\x00C\x00\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01...#$\x82\x08f\xe5A\xc6\xe2G\xe4I\xa9\x18\x96.\xa7\x18T\x0e\x08\xe0\x92q\x9c\x9e\xa4s\xd3\xb7j(\xa0\n\xa4\x95\x00\x03\xdd\x87\xafC\xefE\x14P\x07\xff\xd9', imgid = '18' /usr/lib/python2.3/site-packages/MySQLdb/cursors.py in execute(self=MySQLdb.cursors.Cursor object, query='UPDATE Images SET Image=\xff\xd8\xff\xe0\x00\x10JFIF\x00\x01\x01\x01\x00\x00\x00\x00\x00\x00\xff\xdb\x00C...\xe0\x92q\x9c\x9e\xa4s\xd3\xb7j(\xa0\ n\xa4\x95\x00\x03\xdd\x87\xafC\xefE\x14P\x07\xff\xd9 WHERE\n\t\t\t\tImgID = 18', args=None) 93 94 del self.messages[:] 95 return self._execute(query, args) 96 97 def _execute(self, query, args): self = MySQLdb.cursors.Cursor object, self._execute = bound method Cursor._execute of MySQLdb.cursors.Cursor object, query = 'UPDATE Images SET Image=\xff\xd8\xff\xe0\x00\x10JFIF\x00\x01\x01\x01\x00\x00\x00\x00\x00\x00\xff\xdb\x00C...\xe0\x92q\ x9c\x9e\xa4s\xd3\xb7j(\xa0\n\xa4\x95\x00\x03\xdd\x87\xafC\xefE\x14P\x07\xff\xd9 WHERE\n\t\t\t\tImgID = 18', args = None [...] /usr/lib/python2.3/site-packages/MySQLdb/connections.py in defaulterrorhandler(connection=_mysql.connection open to 'localhost' at 691500, cursor=MySQLdb.cursors.Cursor object, errorclass=class _mysql_exceptions.OperationalError, errorvalue=_mysql_exceptions.OperationalError instance) 31 else: 32 connection.messages.append(error) 33 raise errorclass, errorvalue 34 35 errorclass = class _mysql_exceptions.OperationalError, errorvalue = _mysql_exceptions.OperationalError instance OperationalError: (1054, Unknown column '\xff\xd8\xff\xe0' in 'field list') args = (1054, Unknown column '\xff\xd8\xff\xe0' in 'field list') ---SNIP- the problem is obviously, that the 'string' Image contains characters that make it end ealier than expected. converting a binary image into a string doesn't seem like it would be wise, but like I said, I've never tried it. At any rate, your function would look like this: i've been told on #python that unix doesn't differ between binary and ascii, thus storing binary data should be no problem. i've no glue about how to solve this problem. even if i use quotation marks of any kind for the mysql values, what sometimes circumvents the problem above, at best some some 1000 byte big blob is stored in the mysql database, what is neither an image nor has the size of my uploaded image. any suggestions? bye jonas -- http://mail.python.org/mailman/listinfo/python-list
Re: Interesting decorator use.
On Thu, 24 Feb 2005 15:00:46 -0700, Steven Bethard
[EMAIL PROTECTED] wrote:
Tom Willis wrote:
Question on decorators in general. Can you parameterize those?
If I wanted to something and after the function call for example, I
would expect something like this would work.
def prepostdecorator(function,pre,post):
def wrapper(*args,**kwargs):
pre()
result = function(*args,**kwargs)
post()
return result
return wrapper
def dopre():
print call pre
def dopost():
print call post
@prepostdecorator(pre,post)
def sayhello(Name):
print Hey %s, nice to meet you % Name
#sayhello = prepostdecorator(sayhello,dopre,dopost)
if __name__==__main__:
sayhello(Dude)
but I get ...
TypeError: prepostdecorator() takes exactly 3 arguments (2 given)
You get this TypeError for the same reason that I get the following
TypeError:
py def prepostdecorator(function, pre, post):
... pass
...
py prepostdecorator(1, 2)
Traceback (most recent call last):
File interactive input, line 1, in ?
TypeError: prepostdecorator() takes exactly 3 arguments (2 given)
The expression after @ is a _normal Python expression_. So since you
couldn't call prepostdecorator with 2 arguments in any other situation,
you still can't.
If you want to call prepostdecorator with 2 arguments, you need to write
it this way. A few options:
(1) Use nested functions:
py def prepostdecorator(pre,post):
... def decorator(function):
... def wrapper(*args,**kwargs):
... pre()
... result = function(*args,**kwargs)
... post()
... return result
... return wrapper
... return decorator
...
py @prepostdecorator(dopre, dopost)
... def sayhello(name):
... print Hey %s, nice to meet you % name
...
py sayhello('Tom')
call pre
Hey Tom, nice to meet you
call post
(2) Use functional.partial (PEP 309[1])
py def prepostdecorator(pre, post, function):
... def wrapper(*args,**kwargs):
... pre()
... result = function(*args,**kwargs)
... post()
... return result
... return wrapper
...
py @partial(prepostdecorator, dopre, dopost)
... def sayhello(name):
... print Hey %s, nice to meet you % name
...
py sayhello('Tom')
call pre
Hey Tom, nice to meet you
call post
(3) Use a class:
py class prepostdecorator(object):
... def __init__(self, pre, post):
... self.pre, self.post = pre, post
... def __call__(self, function):
... def wrapper(*args,**kwargs):
... self.pre()
... result = self.function(*args,**kwargs)
... self.post()
... return result
... return wrapper
py @prepostdecorator(dopre, dopost)
... def sayhello(name):
... print Hey %s, nice to meet you % name
...
py sayhello('Tom')
call pre
Hey Tom, nice to meet you
call post
Note that in all of the above cases, the result of evaluating the
expression after the @ is a callable object that takes _exactly one_
argument, the function to be decorated.
HTH,
STeVe
[1] http://www.python.org/peps/pep-0309.html
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Wow thanks for the explanation!! Some of it is a bit mind bending to
me at the moment , but I'm going to mess with it a bit.
--
Thomas G. Willis
http://paperbackmusic.net
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Re: Python Online Programming Contest
[Varun] For details about samhita http://www.samhita.info/ The Madras Institute of Technology (MIT) it says there. The MIT acronym is taken already guys.. -- no scheme no glory -- http://mail.python.org/mailman/listinfo/python-list
Re: Python Online Programming Contest
Varun [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] Hi Friends, Department of Information Technology, Madras Institute of Technology, Anna University, India is conducting a technical symposium, Samhita. As a part of samhita, an Online Programming Contest is scheduled on Sunday, 27 Feb 2005. Looks like a fun symposium. This is the first Online Programming Contest in India to support Python . Other languages supported are C and C++. For Registration and Rules of the contest, http://www.samhita.info/opc Is this open worldwide or India residents only? I could not find a time, either local or UTC. For details about samhita http://www.samhita.info/ Terry J. Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: Interesting decorator use.
Tom Willis wrote: Question on decorators in general. Can you parameterize those? Wow thanks for the explanation!! Some of it is a bit mind bending to me at the moment , but I'm going to mess with it a bit. Oh, I also should have mentioned that there's some explanation at: http://www.python.org/peps/pep-0318.html Specifically on parameterizing: The current syntax also allows decorator declarations to call a function that returns a decorator: @decomaker(argA, argB, ...) def func(arg1, arg2, ...): pass This is equivalent to: func = decomaker(argA, argB, ...)(func) The rationale for having a function that returns a decorator is that the part after the @ sign can be considered to be an expression (though syntactically restricted to just a function), and whatever that expression returns is called. See declaration arguments [15]. But playing around with it is, IMHO, definitely the best way to figure it out. =) STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: pyGoogle is fun and easy to use, and thinks Python is the best programming language
Regrettably, inserting Visual Basic into the list produces a different winner. I think you want some very subtle hard coding which limits it to on-space-delimited languages :-( - Andy -- http://mail.python.org/mailman/listinfo/python-list
Re: Python and Ajax technology collaboration
Chris [EMAIL PROTECTED] wrote: Does anyone else have any Nevow examples? Nevow SVN is full of examples ranging from a simple hello world to a complete blog engine with xml-rpc, smtp and web interfaces for adding new posts and an atom feed, or even a live chat or a pastebin or an image uploader and so on. -- Valentino Volonghi aka Dialtone Now Running MacOSX 10.3.8 Blog: http://vvolonghi.blogspot.com http://weever.berlios.de -- http://mail.python.org/mailman/listinfo/python-list
Re: Python and Ajax technology collaboration
John Willems wrote: Interesting GUI developments, it seems. Anyone developed a Ajax application using Python? Very curious Not what you meant, perhaps, but http://weboggle.shackworks.com has a Javascript/HTML/CSS one-page client that uses XMLHttpRequest to talk to a Python back-end. The requests are very crude, though, and the server is utterly specialized (no framework, not even asyncore). Cheers, Evan @ 4-am -- http://mail.python.org/mailman/listinfo/python-list
Re: Python Online Programming Contest
Will Stuyvesant said the following on 2/24/2005 5:10 PM: [Varun] For details about samhita http://www.samhita.info/ The Madras Institute of Technology (MIT) it says there. The MIT acronym is taken already guys.. Will - It is a local acronym! -- http://mail.python.org/mailman/listinfo/python-list
Re: Canonical way of dealing with null-separated lines?
On Thu, 24 Feb 2005 16:51:22 -0500, Christopher De Vries [EMAIL PROTECTED] wrote: [snip] I think this is a definite improvement... especially putting the buffer size and line terminators as optional arguments, and handling empty files. I think, however that the if splitstr[-1]: ... else: ... clauses aren't necessary, Indeed. Any efficiency gain would be negated by the if test and it's only once per buffer-full anyway. I left all that stuff in to show that I had actually analyzed the four cases i.e. it wasn't arrived at by lucky accident. so I would probably reduce it to this: [snip] Popping off that last member and then iterating over the rest of the list as you suggested is so much more efficient, and it looks a lot better. Yeah. If it looks like a warthog, it is a warthog. The converse is of course not true; examples of elegant insufficiency abound. Cheers, John -- http://mail.python.org/mailman/listinfo/python-list
Re: Interesting decorator use.
On Thu, 24 Feb 2005 15:20:30 -0700, Steven Bethard [EMAIL PROTECTED] wrote: Tom Willis wrote: Question on decorators in general. Can you parameterize those? Wow thanks for the explanation!! Some of it is a bit mind bending to me at the moment , but I'm going to mess with it a bit. Oh, I also should have mentioned that there's some explanation at: http://www.python.org/peps/pep-0318.html Specifically on parameterizing: The current syntax also allows decorator declarations to call a function that returns a decorator: @decomaker(argA, argB, ...) def func(arg1, arg2, ...): pass This is equivalent to: func = decomaker(argA, argB, ...)(func) The rationale for having a function that returns a decorator is that the part after the @ sign can be considered to be an expression (though syntactically restricted to just a function), and whatever that expression returns is called. See declaration arguments [15]. But playing around with it is, IMHO, definitely the best way to figure it out. =) STeVe -- http://mail.python.org/mailman/listinfo/python-list Getting back to your recipe. Through the explanation of how to get parameters in there, I see how it is possible to get a logger in there. Pretty slick that python can have AOP-like features sort of out of the box. Thanks again, off to check out the link... -- Thomas G. Willis http://paperbackmusic.net -- http://mail.python.org/mailman/listinfo/python-list
Re: duplicate file finder
It looks pretty good, but I'll have to take a better look later. Out of
curiosity, why did you convert the first spaces to pipes rather than add
the code as an attachment?
Lowell
Christos TZOTZIOY Georgiou wrote:
On Wed, 23 Feb 2005 01:56:02 -0800, rumours say that Lowell Kirsh
[EMAIL PROTECTED] might have written:
Good idea about hashing part of the file before comparing entire files.
It will make the script longer but the speed increase will most likely
make it worth it.
My dupefind module was one of the first modules I wrote in python (it was a
shell script once...), so it's not appropriate to post. However, rewriting it
was in my RSN list; after your post, I said, what the heck :)
I wouldn't describe it as /clean/ Python code, so any comments on style,
methodology (and of course, bugs!) are mostly welcome. If you have any ideas
how to make it more Pythonic in style, perhaps we can even send it to ASPN.
On the upside, it's a good demo of Python dynamism and therefore power.
All first spaces are converted to pipe symbols to keep code indents, and sorry
for the assignment operators lacking spacing at the left, but it helped me know
what I meant in C, so I kept the habit in Python.
dupefinder.py -- a module to find duplicate files.
find_duplicate_files(*paths):
. A function returning an iterable of lists of duplicate files
. To be used as
. for duplicate_files in dupefinder.find_duplicate_files(dir1, dir2...):
. # process every group of duplicates
import os, md5, errno, sys
IGNORED_ERROR_CODES= frozenset( [errno.EACCES, errno.ENOENT] )
class File(object):
. A wrapper for files to facilitate their comparison.
.
. Interface:
. - .get_hash(level) returns appropriate key for the current cmp level
. - .filename
. - .size
. __slots__= filename, size, _hashes,
. def __init__(self, filename):
. self.filename= filename
. self.size= os.path.getsize(filename)
. if self.size == 0:
. self._hashes= [0, None, None]
. else:
. self._hashes= [self.size]
. def __repr__(self):
. return %s('%s') % (self.__class__.__name__, self.filename)
. def get_hash(self, level):
. Return appropriate key for level of comparison.
. level == 0 returns file size
. level == 1 returns hash of first few kb
. level == 2 returns md5 sum of whole file
. if level = len(self._hashes):
. if 1 = len(self._hashes):
. self._hashes.append(self._get_partial_hash())
. if 2 = len(self._hashes):
. self._hashes.append(self._get_full_hash())
. return self._hashes[level]
. def _get_partial_hash(self):
. fp= open(self.filename)
. try:
. return hash(fp.read(8192))
. finally:
. fp.close()
. def _get_full_hash(self):
. fp= open(self.filename, rb)
. full_hash= md5.new()
. while 1:
. data= fp.read(65536)
. if not data: break
. full_hash.update(data)
. fp.close()
. return full_hash.digest()
class GenericFilesDict(dict):
. A virtual wrapper for the dictionaries of file comparisons.
. Not to be used on its own, but through subclassing.
.
. Each subclass should define a _level class attribute to be used with the
. File.get_hash method, and a _next_class attribute pointing to the class
. managing the next level comparisons.
. __slots__= ()
. def add_file(self, fileobj):
. Add a File object to self keyed by the appropriate key based on
. self._level. If another file object exists in the same spot, replace it
. by a _next_level_class instance containing the pre-existing and new file
. obj.
. this_hash= fileobj.get_hash(self._level)
. try:
. result = self[this_hash]
. except KeyError:
. self[this_hash]= fileobj
. return
. try: # there was something in slot [this_hash]
. result.add_file(fileobj) # so add fileobj to it
. except AttributeError: # it has no add_file method, so it's a File
. _= self[this_hash]= self._next_class() # make an instance
. _.add_file(result) # add pre-existing
. _.add_file(fileobj) # add new
. def __repr__(self):
. return %s%s % (self.__class__.__name__, dict.__repr__(self))
. def __iter__(self):
. Return all instances of SameFiles (subclass of list).
. for item, value in self.iteritems():
. try: _next_class= value._next_class
. except AttributeError: continue
. if _next_class is None:
. yield value
. else:
. for item in value:
. yield item
class SameFiles(list):
. A list of duplicate files.
. __slots__= ()
. _level= 3
. _next_class= None # search stops here
. def add_file(self, fileobj):
. self.append(fileobj)
class FilesByFullHash(GenericFilesDict):
. A dictionary keyed on md5 hash of whole file.
. The
Nevow examples
There was a request for nevow examples. Nevow is a fantastic web-development framework for Python. I used nevow to create http://www.scipy.org/livedocs/ This site uses nevow and self introspection to produce (live) documentation for scipy based on the internal docstrings. It would be nice to add the capability for users to update the documentation through the web-site. But, that functionality is not complete. The code itself is available in the util directory of scipy which can be checked out of CVS (or browsed). Go to http://www.scipy.org for mor details. -Travis Oliphant -- http://mail.python.org/mailman/listinfo/python-list
Re: searching pdf files for certain info
rbt [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED]... Not really a Python question... but here goes: Is there a way to read the content of a PDF file and decode it with Python? I'd like to read PDF's, decode them, and then search the data for certain strings. I've had success with both: http://www.boddie.org.uk/david/Projects/Python/pdftools/ http://www.adaptive-enterprises.com.au/~d/software/pdffile/pdffile.py although my preference is for the latter as it transparently handles decryption. (I've previously posted an enhancement to the `pdftools` utility that adds decryption handling to it, but now use the `pdffile` library as it handles it better.) The ease of text extraction depends a lot on how the PDFs have been created. --Phil. -- http://mail.python.org/mailman/listinfo/python-list
Converting HTML to ASCII
Hi. I'm looking for a Python lib to convert HTML to ASCII. Of course, a quick Google search showed several options (although, I must say, less than I would expect, considering how easy this is to do in *other* languages... :| ), but, I have 2 requirements, which none of them seem to meet: 1) Be able to handle badly formed, or illegal, HTML, as best as possible. Some of the converters I tried ended up dieing on a weird character (that is, a high ascii char). Others somehow got confused and dumped the JavaScript as well. 2) Not embellish the text in any way - no asterisks, no bracket links, no __ for underlines. Can anyone direct me to something which could help me for this? --Thanks a mil. __ Do you Yahoo!? Yahoo! Mail - Helps protect you from nasty viruses. http://promotions.yahoo.com/new_mail -- http://mail.python.org/mailman/listinfo/python-list
Best IDe
Please i am new to python , whats the best IDE to start with -- http://mail.python.org/mailman/listinfo/python-list
Re: Python Online Programming Contest
Actually MIT is an abbreviation and not an acronym in the true sense of the word :) -- http://mail.python.org/mailman/listinfo/python-list
Re: Best IDe
IDLE, PytonWin and SPE are all free and offer all of the important features you'll see even in commercial IDE's. -- http://mail.python.org/mailman/listinfo/python-list
web status display for long running program
I have a command line Python program that sometimes takes a bit (several minutes) to run. I want to provide an optional method for an impatient user (me!) to check the status of the program. The type and amount of status information doesn't fit nicely into a --verbose or logger -- either too little or too much information at different points. I think an optional web page would be convenient interface. The Python program would listen on some port, and if queried (by me browsing to localhost:12345 for example) would return a pretty status display. Hitting reload would update the status etc. My problem is that I'm not sure how to do this: - I don't want to embed a full web server into the application or require any special PC setup. - I think I know how to listen on a socket, but not sure how to send stuff to to a web browser -- just start with HTML? Or like a CGI script with the header stuff like text/html? (I don't care if I have to write the HTML by hand or can use a toolkit -- not important). - Do I need a separate thread to listen and send the HTML? The application is currently single threaded. I'm confortable with threads, but would prefer to avoid them if possible. Or is there a better/different way of doing this? Any general advice or pointers to some code that already does this would be very much appreciated. Python 2.3, under both Linux Windows if that makes a difference. Thanks, Brian. -- http://mail.python.org/mailman/listinfo/python-list
Re: user interface for python
Mike Meyer wrote: There are no portable programs, only ported programs. -- John Gilmore (?) This doesn't really ring true, unless one insists on defining portable to include the idea of universally. I've got dozens of Python utilities that run equally well on my Linux machines and my Windows machines. I didn't port them, I just wrote them in Python and put them in both places. Maybe I'm missing the point of Gilmore's comment... -Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: [perl-python] generic equivalence partition
Xah Lee wrote:
another functional exercise with lists.
Here's the perl documentation. I'll post a perl and the translated
python version in 48 hours.
=pod
parti(aList, equalFunc)
given a list aList of n elements, we want to return a list that is a
range of numbers from 1 to n, partition by the predicate function of
equivalence equalFunc. (a predicate function is a function that
takes two arguments, and returns either True or False.)
Note: a mathematical aspect: there are certain mathematical constraints
on the a function that checks equivalence. That is to say, if a==b,
then b==a. If a==b and b==c, then a==c. And, a==a. If a equivalence
function does not satisfy these, it is inconsistent and basically give
meaningless result.
example:
parti([['x','x','x','1'],
['x','x','x','2'],
['x','x','x','2'],
['x','x','x','2'],
['x','x','x','3'],
['x','x','x','4'],
['x','x','x','5'],
['x','x','x','5']], sub {$_[0]-[3] == $_[1]-[3]} )
returns
[[1],['2','3','4'],['5'],['6'],['7','8']];
=cut
In the example given, the input list's elements are lists of 4
elements, and the equivalence function is one that returns True if the
last item are the same.
Note that this is a generic function. The input can be a list whose
elements are of any type. What parti does is to return a partitioned
range of numbers, that tells us which input element are equivalent to
which, according to the predicate given. For example, in the given
example, it tells us that the 2nd, 3rd, 4th elements are equivalent.
And they are equivalent measured by the predicate function given, which
basically tests if their last item are the same integer. (note that if
we want to view the result as indexes, then it is 1-based index. i.e.
counting starts at 1.)
PS if you didn't realize yet, nested lists/dictionaries in perl is a
complete pain in the ass.
PS note that the code sub {$_[0]-[3] == $_[1]-[3]} is what's called
the lambda form, in Perl.
Xah
[EMAIL PROTECTED]
http://xahlee.org/PageTwo_dir/more.html
this is the first thing that came to my mind. i'm sure there are more clever
ways to do this.
elements = [['x', 'x', 'x', '1'],
['x', 'x', 'x', '2'],
['x', 'x', 'x', '2'],
['x', 'x', 'x', '2'],
['x', 'x', 'x', '3'],
['x', 'x', 'x', '4'],
['x', 'x', 'x', '5'],
['x', 'x', 'x', '5']]
pos = {}
for i, element in enumerate(elements):
pos.setdefault(element[-1], []).append(i+1)
p = pos.values()
p.sort()
[[1], [2, 3, 4], [5], [6], [7, 8]]
bryan
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Re: A few q's on python files.
Tim Roberts wrote: There are packages (like py2exe) that can convert your script into an executable, but they are essentially installers. They package your script, and all the scripts and libraries it needs, into a single file along with the interpreter. When the .exe is executed, it extracts the interpreter and the scripts into a temp directory, and fires up the interpreter. Correction: py2exe doesn't really do that at all. At least, not any of the single file or extracting stuff. Py2exe packages all the Python bytecode into a single zip file (library.zip) and also includes all .pyd and .dll files required to run the program, along with a stub .exe file which instantiates an interpreter (from pythonXX.dll) and runs the main script. Installers such as InnoSetup are what you use to do the single file stuff, and when you run them they do the usual Windows installer stuff like extracting files to the installation directory, creating icons, etc. Finally there are tools (names don't come to mind since I don't use them, but they're easy to find) which *can* do that extract to temporary directory thing rather than the InnoSetup type of installer, but they're relatively rarely used I think. -Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: Python Online Programming Contest
Hi, It is open for anyone across the world. All times are local ( GMT +5:30). The contest will be on Feb 27 (this sunday) and i will ensure that the times are clearly specified. -Varun -- http://mail.python.org/mailman/listinfo/python-list
Re: Shift Confusion
Quite. Although you can sort of see how one might naively arrive at this conclusion: one 7-bit char takes 0...127, which when you put it into an 8-bit byte leaves 128...255 unused for a second char James Yep, that's what I was doing. Guess I was too tired to program usefully last night. Thanks for clearing that up, guys! -- http://mail.python.org/mailman/listinfo/python-list
Re: Best IDe
I demo'd wing ide and have to say it's the best commercial offering. The only other one I'm aware of is Komodo and it really can't touch Wing. But for me, wingide was slugish. I have a 1/2 gig of memory and a pretty hefty CPU - i think its a 1.6 Pentium M [it's a company issued laptop -- so im not sure of the specs]. I found that as wing tried to autocomplete identifiers in large name spaces that it would take a second or so. This was really painful when working with wxPython. What wing does have going for it is a REALLY good auto-completion system. Yeah it's slow, but its good. You wing hints as to what objects are by using isinstance(). For example, the code below tells wing that frame is a wx.Frame - # make_frame returns a wx.Frame frame = make_frame() isinstance(frame, wx.Frame) Once wing has a hint, it'll autocomplete the methods / properties for you. But again, it is slow. As far as free software goes, I really like stani's python editor. It seems to *watch* methods that you call on an object and autocomplete based on that. For example suppose it sees this code: # make another wx.Frame frame = make_frame() frame.method1() frame.method2() ... # Below, stani will autocomplete showing you method1 and method 2. # No they aren't valid wx.Frame methods! frame. HTH, jw On 24 Feb 2005 17:31:31 -0800, Harlin Seritt [EMAIL PROTECTED] wrote: IDLE, PytonWin and SPE are all free and offer all of the important features you'll see even in commercial IDE's. -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Flushing print()
gf gf [EMAIL PROTECTED] wrote: : Is there any way to make Python's print() flush : automatically, similar to...mmm...that other : language's $|=1 ? Hello gf gf, Yes; you can use the '-u' command line option to Python, which will turn off stdout/stderr buffering. : If not, how can I flush it manually? sys.stdout.flush() didn't : seem to work. H, that's odd. sys.stdout.flush() should do it. How are you testing that stdout isn't flushing as you expect? Best of wishes to you! -- http://mail.python.org/mailman/listinfo/python-list
Default value for Listbox (Tkinter)
Whenever I set up something similar: vals = ['1', '2','3'] for v in vals: listbox.inset(END, v) I notice that when this listbox is displayed, there is never a default value. How can I make sure that one of the indices is selected by default? Thanks, Harlin -- http://mail.python.org/mailman/listinfo/python-list
Re: web status display for long running program
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Brian Roberts wrote: | I have a command line Python program that sometimes takes a bit | (several minutes) to run. I want to provide an optional method for an | impatient user (me!) to check the status of the program. The type and | amount of status information doesn't fit nicely into a --verbose or | logger -- either too little or too much information at different | points. dd and pppd (and probably others) solve this problem by registering a signal handler that either toggles debug or prints status information to stderr. - -- John Lenton ([EMAIL PROTECTED]) -- Random fortune: Work consists of whatever a body is obliged to do. Play consists of whatever a body is not obliged to do. -- Mark Twain -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.0 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQFCHpMZcxEeCh6qRm8RAg11AKCek0hV6QCHw6fm3TM3KAJIXPb1RQCg4qhy HMr5y+w7fxESkJ2vQ0GEmm0= =c4bs -END PGP SIGNATURE- -- http://mail.python.org/mailman/listinfo/python-list
