ANN: xxgamma 0.06
I'm happy to announce xxgamma 0.06 Get it at http://www.florian-diesch.de/software/xxgamma/ xxgamma is an PyGTK based GUI for xgamma which allows you to load, modify and store multiple gamma correction profiles for XFree86 and X.org through a GUI and a command line interface. Version 0.06 fixes some bugs and adds Undo and some minor GUI improvements Florian -- http://www.florian-diesch.de/ -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
ANN: pycairo release 1.8.4 now available
Pycairo is a set of Python bindings for the multi-platform 2D graphics library cairo. http://cairographics.org http://cairographics.org/pycairo A new pycairo release 1.8.4 is now available from: http://cairographics.org/releases/pycairo-1.8.4.tar.gz http://cairographics.org/releases/pycairo-1.8.4.tar.gz.md5 6adff10f58818004839fe9edc9dc6a9b pycairo-1.8.4.tar.gz Overview of changes from pycairo 1.8.2 to pycairo 1.8.4 === General Changes: Pycairo 1.8.4 requires cairo 1.8.4 (or later) and Python 2.6 Bug Fixes: 20674: Add get/set_extend for Gradient Patterns New Classes: cairo.ToyFontFace New Methods: Pattern.get_extend Pattern.set_extend ToyFontFace.get_family ToyFontFace.get_slant ToyFontFace.get_weight Deleted Methods: SurfacePattern.get_extend SurfacePattern.set_extend Other Changes: Threading for surfaces with stream functions has been reenabled. Documentation updates. Steve -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
ANN: eGenix mxODBC Connect 1.0.1 - Python Database Interface
ANNOUNCING eGenix.com mxODBC Connect Python Database Interface Version 1.0.1 Our new client-server product for connecting Python applications to relational databases - from all major platforms This announcement is also available on our web-site for online reading: http://www.egenix.com/company/news/eGenix-mxODBC-Connect-1.0.1-GA.html INTRODUCTION The mxODBC Connect Database Interface for Python allows users to easily connect Python applications to all major databases on the market today in a highly portable and convenient way. Unlike our mxODBC Python extension, mxODBC Connect is designed as client-server application, so you no longer need to find production quality ODBC drivers for all the platforms you target with your Python application. Instead you use an easy to install Python client library which connects directly to the mxODBC Connect database server over the network. This makes mxODBC Connect the ideal basis for writing cross-platform database programs and utilities in Python, especially if you run applications that need to communicate with databases such as MS SQL Server and MS Access, Oracle Database, IBM DB2 and Informix, Sybase ASE and Sybase Anywhere, MySQL, PostgreSQL, SAP MaxDB and many more, that run on Windows or Linux machines. By removing the need to install and configure ODBC drivers on the client side, mxODBC Connect greatly simplifies setup and configuration of database driven client applications, while at the same time making the network communication between client and database server more efficient and more secure. For more information, please see the product page: http://www.egenix.com/products/python/mxODBCConnect/ NEWS mxODBC Connect 1.0.1 is a patch-level release of our new mxODBC Connect product. * More Robust We have made the client and server more robust in case of communication failures. Even if the client applications fail to shutdown the server connection before exiting, the server will free up resources used by the client on the server side and rollback transactions as necessary. * More Platform Support With the 1.0.1 release we are also providing much better platform support for the mxODBC Connect Client: we have fixed a problem in 1.0.0 that prevented the installation of the pre-built clients on non-Linux systems. The mxODBC Connect Client can now be installed on most platforms supported by Python, since it is written in a platform independent, portable way. The pre-built archives also make it possible to integrate the clients into build system such as buildout (used in Zope and Plone) or other distutils-based deployment systems. * Ideal for Building Bridges As a result, connecting from e.g. Mac OS X to an SQL Server database has never been easier. You can even keep the data sources you already have configured on your Windows machine and connect to them as if your application were running on the database server itself. UPGRADING You are encouraged to upgrade to this latest mxODBC Connect release. When upgrading, please always upgrade both the server and the client installations to the same version - even for patch level releases. Customers who have purchased mxODBC Connect 1.0 licenses can download and upgrade their existing installations without having to purchase new licenses or upgrades. The licenses will continue to work with version 1.0.1. Users of our stand-alone mxODBC product will have to purchase new licenses from our online shop in order to use mxODBC Connect. You can request 30-day evaluation licenses by visiting our web-site or writing to sa...@egenix.com, stating your name (or the name of the company) and the number of eval licenses that you need. http://www.egenix.com/products/python/mxODBCConnect/#Evaluation DOWNLOADS The download archives as well as instructions for installation and configuration of the product can be found on the product page: http://www.egenix.com/products/python/mxODBCConnect/ Evaluation licenses for the server part are available free of charge: http://www.egenix.com/products/python/mxODBCConnect/#Evaluation The client part of mxODBC Connect is always free of charge. ___ SUPPORT Commercial support for this product is available from eGenix.com. Please see http://www.egenix.com/services/support/ for details about our support offerings. Enjoy, -- Marc-Andre Lemburg eGenix.com Professional Python Services directly from the Source (#1, Mar 19 2009)
pylab plot_date problem
Hi ,
I am using following code to create a graph
def plot_plot():
ax = pylab.subplot(111)
for count in range(len(yaxes_values)):
pylab.subplots_adjust(left=0.13, bottom=0.21,
right=0.90, top=0.90,wspace=0.20, hspace=0.20)
ax.plot_date(id_dates,yaxes_values[count],fmt='o-',label=titleList[count])
pylab.xlabel('Time Stamp')
pylab.ylabel('Values')
ax.xaxis.set_major_locator(pylab.MinuteLocator(interval=Interval))
ax.xaxis.set_major_formatter(formatter)
labels = ax.get_xticklabels()
pylab.setp(labels, rotation=90, fontsize=8)
ax.set_title(choice)
pylab.grid()
font= FontProperties(size='x-small');
pylab.legend(loc=0, prop=font)
each time I am re-initilliziing the titleList before calling the
plot_plot , This works fine for one graph,
But if I call it more then once the label keep appending ..
How to get rid of this ?
Regds
Shah Alam
--
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Re: [python-list] Re: Strange crash issue on Windows w/ PyGTK, Cairo...
bieff...@gmail.com wrote: If you have worked with C/C++, you know that memory-related bugs can be very tricky. More than once - working with C code - I had crashes that disappeared if I just added a 'printf', because the memory allocation scheme changed and the memory corrupted was not anymore relevant. Well, you turned out to be dead right about this, as I suppose should have been pretty obvious given the nature of the problems I was having. Anyway, the issue turned out to be zlib.decompress() - for larger sets of data, if I wasn't specifying bufsize, the malloc()s that it was doing behind-the-scenes must have been clobbering memory. As soon as I specified bufsize, everything was totally kosher. Once I'm a bit more awake tomorrow I'll put together a testcase and send it in to the bug tracker. This does bring up one question: for larger chunks of data, is it More Appropriate to use a zlib decompression object instead of just passing it all through zlib.decompress()? Thanks, everyone... -CJ -- http://mail.python.org/mailman/listinfo/python-list
Re: How complex is complex?
When we say readability counts over complexity, how do we define what
level of complexity is ok?
For example:
Say I have dict a = {'a': 2, 'c': 4, 'b': 3}
I want to increment the values by 1 for all keys in the dictionary.
So, should we do:
for key in a:
... a[key] = a[key] + 1
or is it Ok to have code like:
dict(map(lambda key: (key, a[key] + 1), a))
Before doing anything else I'd suggest leaving your code as is,
closing your editor immediately and not touching it at all before the
One True Answer arrives from the PSF.
Please mail your question (along with a self-addressed envelope) to:
Python Software Foundation
P.O. Box 848
Hampton, NH 03843
USA
where python language lawyers will consider it in great detail,
consulting GvR if necessary. Please do not try to figure this one out
by yourself! The PSF lawyers are trained to do this, such things are
better left to professionals, you don't want to shoot yourself in the
foot.
Once every nuanced detail has been carefully weighed in and a
consensus has been reached among the Supreme Python Language
Commission chamber of the PSF the appropriate answer will be mailed
back to you.
Now you should be able to open up your favorite editor and hack away
knowing full well that nobody and nothing can stop you, ever!
Cheers,
Daniel
--
Psss, psss, put it down! - http://www.cafepress.com/putitdown
--
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what does 64-bit python mean?
Hi, Could someone help me in understanding what 64-bit python means? tahnks, Srini Add more friends to your messenger and enjoy! Go to http://messenger.yahoo.com/invite/ -- http://mail.python.org/mailman/listinfo/python-list
Re: equivalent of source command in tcl for python
On Mar 19, 2:42 pm, Ralf Schoenian r...@schoenian-online.de wrote: mark.coll...@csiro.au wrote: Many times I am developing a code in a file and I want to, for example, exit at a specific line so that I can test something. In tcl you can just put an exit command in and source the file. Is there an equivalent for python? Thanks, import sys sys.exit() And if you run your code using the -i switch, a la: python -i mycode.py Python will open the interpreter in interactive mode after it hits sys.exit() (or any uncaught exception), with the full state of the program up to that point available. Which can be very handy during testing for ensuring that your expectations of that state are correct. -- http://mail.python.org/mailman/listinfo/python-list
Re: what does 64-bit python mean?
On Wed, Mar 18, 2009 at 11:45 PM, srinivasan srinivas sri_anna...@yahoo.co.in wrote: Hi, Could someone help me in understanding what 64-bit python means? It's been compiled for 64-bit processors, so it uses 64-bit pointers and 64-bit small integers. And I would think it would only work w/ C extension libraries also compiled for 64-bit CPUs. So, the same meaning 64-bit has for anything else really. Cheers, Chris -- I have a blog: http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: what does 64-bit python mean?
Chris Rebert wrote: It's been compiled for 64-bit processors, so it uses 64-bit pointers and 64-bit small integers. And I would think it would only work w/ C extension libraries also compiled for 64-bit CPUs. So, the same meaning 64-bit has for anything else really. A 64bit build of Python doesn't necessarily mean that the small integer type is 64bit, too. Python uses the datatype long on all platforms. On Windows sizeof(long) == 4 (four bytes) on 32 and 64 versions of Windows. Christian -- http://mail.python.org/mailman/listinfo/python-list
Re: what does 64-bit python mean?
Could someone help me in understanding what 64-bit python means? While Chris' answer is correct, it doesn't show the consequences of using a 64-bit Python. Primarily, these are: - strings, Unicode objects, lists, dicts, and tuples can have more than 2**31 elements. - you can load 64-bit DLLs into the Python process, and 64-bit applications (such as a 64-bit Apache or IIS process) can load the Python interpreter into their address spaces. - you need a 64-bit operating system to run Python The first item is only relevant if a) you have that much data that you want to put into a single container, and b) you have that much memory to keep the entire container in memory. For a list with 2**31 elements, you need 16GiB of memory to represent the list alone, not counting the actual data (e.g. for a list of 2**31 Nones). For a dict, you need more than 48GiB for the dict alone. For a byte string, 2GiB are enough to get past the 2**31 elements boundary. I just noticed that this description is not completely correct: in a 32-bit process, the upper size of collections is actually smaller than 2**31. For a list, you can have only up to 2**30 elements in the list; on many operating systems, only 2**29. For a dict, the maximum number of elements is even smaller, around 250 millions. So you would need a 64-bit Python already to get past these boundaries. Regards, Martin -- http://mail.python.org/mailman/listinfo/python-list
Re: REDIRECT
On Thu, Mar 19, 2009 at 4:30 AM, gaeasian...@gmail.com wrote: On Mar 18, 5:21 am, Tino Wildenhain t...@wildenhain.de wrote: gaeasian...@gmail.com wrote: 3. GoogleAppEngine, Version 1.1.9 (webapp - framework) What actually I'm try to do is : I'm having a Login page which developed in HTML. When I click on the Login button I want the page to validate (at datastore of google app) using python and redirect to other HTML page. As what I understand, Python is the only language that supported by the GoogleApps. http://code.google.com/appengine/docs/python/tools/webapp/redirects.html Does that help? -- http://mail.python.org/mailman/listinfo/python-list
Re: Do deep inheritance trees degrade efficiency?
Anthra Norell wrote: Would anyone who knows the inner workings volunteer to clarify whether or not every additional derivation of a class hierarchy adds an indirection to the base class's method calls and attribute read-writes. In C++, I suppose, a three-level inheritance would resolve into something like *(*(*(*(base_class_method (). I think in C++ the compiler can often resolve the correct class statically. Python currently walks through the entire hierarchy. $ cat inherit.py class A(object): def m(self): return 42 B = A for i in range(1000): class B(B): pass a = A() b = B() if __name__ == __main__: print a.m() print b.m() $ python -m timeit -sfrom inherit import a a.m 1000 loops, best of 3: 0.173 usec per loop $ python -m timeit -sfrom inherit import b b.m 1 loops, best of 3: 68.7 usec per loop Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: Do deep inheritance trees degrade efficiency?
On Wed, Mar 18, 2009 at 6:09 AM, Anthra Norell anthra.nor...@bluewin.ch wrote: Would anyone who knows the inner workings volunteer to clarify whether or not every additional derivation of a class hierarchy adds an indirection to the base class's method calls and attribute read-writes. In C++, I suppose, a three-level inheritance would resolve into something like *(*(*(*(base_class_method (). There's no effect on attribute read-writes as they all take place within the single __dict__ of the instance. As for method lookup, it doesn't add an indirection per se, but rather the list of classes to look thru to find a method gets longer, making base-class method lookups slower. IIRC, a typical method lookup does something like the following pseudocode: for klass in the_object.__mro__: if method_name in klass.__dict__: return klass.__dict__[method_name] raise AttributeError # no such attribute The __mro__ being the Method Resolution Order, a list containing the_object's class and that class' superclasses. __dict__ is the namespace dictionary of an individual class. However, you shouldn't really worry about the inefficiency of a deep inheritance tree as Python's dictionary implementation (used for namespace lookup) is super-optimized, and in any case the inefficiency ought to be negligible compared to the actual work done in the program (if it's not, there's something wrong with how the program has been coded). [Note: I'm purposefully ignoring the fact that methods and attributes are in reality looked up in the exact same way for simplicity/clarity.] Cheers, Chris -- I have a blog: http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: How complex is complex?
On Mar 19, 11:29 am, Daniel Fetchinson fetchin...@googlemail.com
wrote:
When we say readability counts over complexity, how do we define what
level of complexity is ok?
For example:
Say I have dict a = {'a': 2, 'c': 4, 'b': 3}
I want to increment the values by 1 for all keys in the dictionary.
So, should we do:
for key in a:
... a[key] = a[key] + 1
or is it Ok to have code like:
dict(map(lambda key: (key, a[key] + 1), a))
Before doing anything else I'd suggest leaving your code as is,
closing your editor immediately and not touching it at all before the
One True Answer arrives from the PSF.
Please mail your question (along with a self-addressed envelope) to:
Python Software Foundation
P.O. Box 848
Hampton, NH 03843
USA
where python language lawyers will consider it in great detail,
consulting GvR if necessary. Please do not try to figure this one out
by yourself! The PSF lawyers are trained to do this, such things are
better left to professionals, you don't want to shoot yourself in the
foot.
Once every nuanced detail has been carefully weighed in and a
consensus has been reached among the Supreme Python Language
Commission chamber of the PSF the appropriate answer will be mailed
back to you.
Now you should be able to open up your favorite editor and hack away
knowing full well that nobody and nothing can stop you, ever!
Cheers,
Daniel
--
Psss, psss, put it down! -http://www.cafepress.com/putitdown
I understand that my question was foolish, even for a newbie.
I will not ask any more such questions in the future.
--
http://mail.python.org/mailman/listinfo/python-list
Re: Do deep inheritance trees degrade efficiency?
Chris Rebert wrote: There's no effect on attribute read-writes as they all take place within the single __dict__ of the instance. As for method lookup, it doesn't add an indirection per se, but rather the list of classes to look thru to find a method gets longer, making base-class method lookups slower. IIRC, a typical method lookup does something like the following pseudocode: for klass in the_object.__mro__: if method_name in klass.__dict__: return klass.__dict__[method_name] raise AttributeError # no such attribute Your assumption is no longer true. Starting with Python 2.6 and 3.0 the lookup of attributes is cached. You can find detailed information by searching for VERSION_TAG in the source code. Christian -- http://mail.python.org/mailman/listinfo/python-list
Re: Roulette wheel
Il Wed, 18 Mar 2009 23:31:09 -0200, Gabriel Genellina ha scritto: En Wed, 18 Mar 2009 18:49:19 -0200, mattia ger...@gmail.com escribió: Il Wed, 18 Mar 2009 13:20:14 -0700, Aahz ha scritto: In article 49c1562a$0$1115$4fafb...@reader1.news.tin.it, mattia ger...@gmail.com wrote: Yeah, and I believe that we can say the same for: 1 - t = [x*2 for x in range(10)] 2 - t = list(x*2 for x in range(10)) or not? The latter requires generator expressions, which means it only works with Python 2.4 or higher. Personally, I think that if the intent is to create a list you should just use a listcomp instead of list() on a genexp. Ok, so list(x*2 for x in range(10)) actually means: list((x*2 for x in range(10)) -- so a generator is created and then the list function is called? Exactly. The (()) were considered redundant in this case. Also, dealing with memory, [...] will be deleted when the reference will be no longer needed and with list(...)... well, I don't know? I'm new to python so sorry if this are nonsense. I don't completely understand your question, but *any* object is destroyed when the last reference to it is gone (in CPython, the destructor is called at the very moment the reference count reaches zero; other implementations may behave differently). OK, understood. Now, as a general rule, is it correct to say: - use generator expression when I just need to iterate over the list or call a function that involve an iterator (e.g. sum) and get the result, so the list is not necessary anymore - use list comprehensions when I actually have to use the list (e.g. I need to swap some values or I need to use sorted() etc.) Am I right? -- http://mail.python.org/mailman/listinfo/python-list
Re: Do deep inheritance trees degrade efficiency?
Peter Otten wrote: Anthra Norell wrote: Would anyone who knows the inner workings volunteer to clarify whether or not every additional derivation of a class hierarchy adds an indirection to the base class's method calls and attribute read-writes. In C++, I suppose, a three-level inheritance would resolve into something like *(*(*(*(base_class_method (). I think in C++ the compiler can often resolve the correct class statically. Python currently walks through the entire hierarchy. currently meaning 2.5 here... $ cat inherit.py class A(object): def m(self): return 42 B = A for i in range(1000): class B(B): pass a = A() b = B() if __name__ == __main__: print a.m() print b.m() $ python -m timeit -sfrom inherit import a a.m 1000 loops, best of 3: 0.173 usec per loop $ python -m timeit -sfrom inherit import b b.m 1 loops, best of 3: 68.7 usec per loop [Christian Heimes] Your assumption is no longer true. Starting with Python 2.6 and 3.0 the lookup of attributes is cached. You can find detailed information by searching for VERSION_TAG in the source code. I missed that change. Here are the 2.6 timings: $ python2.6 -m timeit -sfrom inherit import a a.m 1000 loops, best of 3: 0.171 usec per loop $ python2.6 -m timeit -sfrom inherit import b b.m 1000 loops, best of 3: 0.169 usec per loop Impressing. Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: How complex is complex?
On Thu, Mar 19, 2009 at 9:39 AM, Kottiyath n.kottiy...@gmail.com wrote: I understand that my question was foolish, even for a newbie. I will not ask any more such questions in the future. -- http://mail.python.org/mailman/listinfo/python-list I didn't think it was a foolish question, just one with a very subjective (and perhaps unknowable) answer. I have a feeling that Daniel wasn't intending to come off as snarky, but who knows. What someone considers 'readable' or 'complex' is going to vary from individual to individual. If you look at it (or if a peer on roughly the same skill level as you looks at it) and has to squint really hard to figure out what it's doing, it's probably not readable enough - which may or may not be linked to the complexity of the code itself (Depending on how what you mean by complexity - number of instructions? number of characters? special charachters? number of tokens? levels of indirection? etc). -- http://mail.python.org/mailman/listinfo/python-list
Re: read web page that requires javascript on client
On Thu, Mar 19, 2009 at 1:25 AM, Carl tg2.u...@gmail.com wrote: Probably the easiest thing is to actually use a browser. There are many examples of automating a browser via Python. So, you can programmatically launch the browser, point it to the JavaScript afflicted page, let the JS run and grab the page source. As an added bonus you can later interact with the page by programatically, filling form fields, selecting options from lists and clicking buttons. HTH, Carl -- http://mail.python.org/mailman/listinfo/python-list I've been using the python port of mechanize (specifically mechanize.browser) for web automation, it's rather nice.[1] In the vast majority of cases, if I need something done with javascript, it's just to generate a url or post data - in which case I can just read the javascript, and figure out what it's doing - or use something like livehttpheaders[2] to find out what I need to be sending. This obviously doesn't cover every single case, but it works pretty fine most of the time. I would love to see a complete javascript interpreter / dom interface in python - but it's hard, hard stuff. I'd love to even have the time to read the ECMAScript spec enough to have enough working knowledge of javascript's internals to be able to contribute to one of the current attempts at doing so. 1. http://wwwsearch.sourceforge.net/mechanize/ 2. https://addons.mozilla.org/en-US/firefox/addon/3829 -- http://mail.python.org/mailman/listinfo/python-list
Re: read web page that requires javascript on client
You can try and use wxpythons broswer to execute the javascript On Wed, Mar 18, 2009 at 10:01 PM, Greg gregsaundersem...@gmail.com wrote: Hello all, I've been trying to find a way to fetch and read a web page that requires javascript on the client side and it seems impossible. I've read several threads in this group that say as much but I just can't believe it to be true (I'm subscribing to the argument of personal incredulity here). Clearly urllib and urllib2 don't seem to support this and I've looked at win32com.client and it's ScriptControl but that doesn't seem to be viable approach for this particular problem. Does anyone have any suggestions, hack or ideas or am I missing something really obvious. Thanking you all in advance! Greg -- http://mail.python.org/mailman/listinfo/python-list -- http://www.goldwatches.com/Watches.asp?Brand=71 -- http://mail.python.org/mailman/listinfo/python-list
Re: python equivalent of java technologies
On Tue, Mar 17, 2009 at 8:32 PM, Armin feng.sh...@gmail.com wrote: You could tell her to try Jython. In that, you can just use the Java implementations. :) Plus, you have things in Jython that Java doesn't :D -- Armin Moradi -- http://mail.python.org/mailman/listinfo/python-list Exactly. Her challenges to find stuff have to do with the JVM, not Java the language. Python runs on the JVM. -- http://mail.python.org/mailman/listinfo/python-list
Unicode problem in ucs4
Hi,
I have a C extension, which takes a unicode or string value from
python and convert it to unicode before doing more operations on it.
The skeleton looks like:
static PyObject *unicode_helper( PyObject *self, PyObject *args){
PyObject *sampleObj = NULL;
Py_UNICODE *sample = NULL;
if (!PyArg_ParseTuple(args, O, sampleObj)){
return NULL;
}
// Explicitly convert it to unicode and get Py_UNICODE value
sampleObj = PyUnicode_FromObject(sampleObj);
sample = PyUnicode_AS_UNICODE(sampleObj);
// perform other operations.
.
}
This piece of code is working fine on python with ucs2 configuration
but fails with python ucs4 config. By failing, I mean that only the
first letter comes in variable sample i.e. if I pass test from
python then sample will contain only t. However, PyUnicode_GetSize
(sampleObj) function is returning correct value (4 in this case).
Any idea on why this is happening? Any help will be appreciated.
Regards,
Abhigyan
--
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Re: Style formating of multiline query, advise
On Mar 19, 10:26 am, Marco Mariani ma...@sferacarta.com wrote: someone wrote: Also, for SQL, (A) why are you using nested joins?, and inner select produce smaller set which is then joined with other table, kind a optimization Did you time it? I've done some kind of a optimization that slowed queries by tenfold, because postgres didn't need my advice, and knew better. RDBMS Query itself is fast. I'll try to time it and will report my results here :) performance is non-intuitive, really. If you're using mysql, YMMV, because its optimizer is not as good. That's true, I don't trust optimizer Yes, my original question was about formatting. It's not original query (only a part). Try this: http://www.dpriver.com/pp/sqlformat.htm My 2c: I use textwrap.dedent to strip leading spaces from every line. textwrap.dedent? What's that? I'm new in python. Will google it. How do your query formatting looks like then? -- http://mail.python.org/mailman/listinfo/python-list
Style formating of multiline query, advise
Hi, what is good :) style for multiline queries to database? Is that one ok? query = SELECT * FROM ( SELECT a.columna, a.columnb, a.iso FROM all a WHERE (a.name = LOWER(%s)) ) AS c JOIN other as b on c.gid = b.id WHERE class = 'A' ORDER BY population DESC LIMIT %s; Regards, Pet -- http://mail.python.org/mailman/listinfo/python-list
Re: python equivalent of java technologies
Oops , for RIA there is always pyjamas (gwt for python ;-) T On Mar 19, 7:52 pm, Tim Hoffman zutes...@gmail.com wrote: Hi Well zope has quite a few of these out of the box and have been around for a bit longer than some of the java options. Specifically persistence (ZODB persistence in zope is pretty much completely autmomatic) you can inplement web services with it (xmlrpc out of the box, though I assume you mean soap) zope encompasses security/ and authentication and can easily be integrated with a range of single signon environments. there are a range of scheduling services in to, but which is most like quartz I am not sure about. zope does support distributed transactions, but I not XA , but is ACID. In general there are a heap of interfaces for python do different message queues/buses, take you pick of you favourite platform. Not sure about reporting that is equivalent to jasper. T On Mar 19, 3:14 am, markolopa marko.lopa...@gmail.com wrote: Hello, When comparing python and java with a colleague who is fan of java, she challenged me to find in python the equivalent to the following technologies. Could you please help telling if we have something equivalent in python or not and how they compare to the java solutions? - persistance framework (~hibernate) - transational monitor (distributed transaction), XA compliance (message system, DB) (http://en.wikipedia.org/wiki/X/Open_XA) - web openess sur le web (web service) - RIA and web deployable graphic library - scheduling (quartz) - secutity (PKI, single sign-on...) - reporting (Jasper) Thanks a lot! Marko -- http://mail.python.org/mailman/listinfo/python-list
Re: split problem if the delimiter is inside the text limiter
On 2009-03-19 00:30, Tim Chase wrote: Bruno Desthuilliers wrote: Tim Chase a écrit : (if your columns in your CSV happen to match the order of your INSERT statement, you can just use execute(sql, tuple(row)) Or more simply: cursor.execute(sql, row) that's always annoyed me with the mxODBC drivers I've usedthey require(d?) a tuple in this position, so I developed this habit. I think the OP hinted they were using postgres drivers which may be a bit kinder to the user. This requirement in mxODBC results from still providing a DB-API 1.0 compatible interface... after all, it's been around since 1997. Back in the early days, there was only cursor.execute() and the only way to differentiate between a list of rows and a single row was by type. DB-API 2.0 has cursor.executemany() to make this differentiation at the API level. mxODBC will lift this requirement in the next version, promised :-) (and don't get me started on mxODBC's failure to determine the data-type for parameters in subqueries, raising exceptions on perfectly valid queries/rant) I'm not sure what you are referring to here. mxODBC can only provide an interface to the underlying ODBC driver. If the ODBC driver does not provide the required information or reports errors in situations where you don't expect them, mxODBC can try to work around these things (and does for quite a few drivers), but of course, we cannot cover all possible cases, since there are far too many ODBC drivers out there, each with their own release cycles. That said, we are always open to reports about such issues so we can work them into mxODBC updates where possible. -- Marc-Andre Lemburg eGenix.com Professional Python Services directly from the Source (#1, Mar 19 2009) Python/Zope Consulting and Support ...http://www.egenix.com/ mxODBC.Zope.Database.Adapter ... http://zope.egenix.com/ mxODBC, mxDateTime, mxTextTools ...http://python.egenix.com/ ::: Try our new mxODBC.Connect Python Database Interface for free ! eGenix.com Software, Skills and Services GmbH Pastor-Loeh-Str.48 D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg Registered at Amtsgericht Duesseldorf: HRB 46611 http://www.egenix.com/company/contact/ -- http://mail.python.org/mailman/listinfo/python-list
problem with Pamie (textbox editing)
Hi,
I try to test web aplication with using of modul Pamie and I have next problem,
when I edit any textbox or textarea and consequently press the button which
works the data
in this textbox, so this textbox returns into the state before editing,
fof example:
Let I have 3 textboxes: box1, box2 and result
and 1 button: count, which fill sum of box1 and box2 in the textbox
result
after using textBoxSet('box1','10') and textBoxSet('box2','10') is in both
textboxes number 10,
but using buttonClick('count') delete number 10 in box1 and box2 and both
return to the state before editing (empty),
here is my code:
#
from cPAMIE import PAMIE
ie = PAMIE()
ie.navigate(url)
ie.textBoxSet('att$text_TBName','name')
ie.buttonClick(att$text_TBName)
time.sleep(3)
ie.elementClick(ie.elementFind(Input,name,att$copyTBProxy2A))
#
I tried it also without Pamie, but the result is the same:
#
from win32com.client import DispatchEx
ie = DispatchEx('InternetExplorer.Application')
ie.navigate(url)
ie.visible = 1
time.sleep(3)
el = ie.document.getElementsByTagName('input')
i=0
while (el[i].getAttribute('Name') att$text_TBNname):
i+=1
el[i].value = 'name'
j=0
while (el[j].getAttribute('Name') att$copyTBProxy2A):
j+=1
el[j].click()
#
application is ok, because
when I make it manual, so it works OK,
can somebody help me, what I make wrong,
thanks
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lipo: can't figure out the architecture type of
Hi, I am getting an gcc compilation error while installing FSEvents (http://pypi.python.org/packages/source/p/pyobjc-framework-FSEvents/ pyobjc-framework-FSEvents-2.2b1.tar.gz) package on my Mac (OS X 10.4.11, Intel Core Duo 32 bit processor, Python2.6.1, gcc: i686-apple- darwin8-gcc-4.0.1) gcc failed while building the FSEvents._callbacks extension on $ python setup.py install here is the error trace... running install_lib running build_py running build_ext building 'FSEvents._callbacks' extension gcc -arch ppc -arch i386 -isysroot /Developer/SDKs/MacOSX10.4u.sdk - fno-strict-aliasing -fno-common -dynamic -DNDEBUG -g -O3 -I/Library/ Frameworks/Python.framework/Versions/2.6/include/python2.6 -c Modules/ _callbacks.m -o build/temp.macosx-10.3-i386-2.6/Modules/_callbacks.o - O0 Modules/_callbacks.m:60: error: parse error before 'm_python_context_template' Modules/_callbacks.m:62: warning: excess elements in scalar initializer Modules/_callbacks.m:62: warning: (near initialization for 'm_python_context_template') Modules/_callbacks.m:63: warning: excess elements in scalar initializer . . . . (Error ending with) Modules/_callbacks.m:133: error: previous definition of 'result' was here Modules/_callbacks.m:353: error: parse error before 'FSEventStreamRef' lipo: can't figure out the architecture type of: /var/tmp// cco6kalc.out error: command 'gcc' failed with exit status 1 Could someone help me in solving this compilation error? -- http://mail.python.org/mailman/listinfo/python-list
Do deep inheritance trees degrade efficiency?
Would anyone who knows the inner workings volunteer to clarify whether or not every additional derivation of a class hierarchy adds an indirection to the base class's method calls and attribute read-writes. In C++, I suppose, a three-level inheritance would resolve into something like *(*(*(*(base_class_method (). Frederic -- http://mail.python.org/mailman/listinfo/python-list
Re: mxODBC (was split problem if the delimiter is inside the text limiter)
DB-API 2.0 has cursor.executemany() to make this differentiation at the API level. mxODBC will lift this requirement in the next version, promised :-) glad to hear...will executemany() take an arbitrary iterable? My (albeit somewhat-antiquated) version balked at anything that wasn't a list/tuple (don't remember off the top of my head which it was). For a lot of my ETL work, it would be nice to pass a generator so I don't have to keep huge datasets in memory. (and don't get me started on mxODBC's failure to determine the data-type for parameters in subqueries, raising exceptions on perfectly valid queries/rant) I'm not sure what you are referring to here. mxODBC can only provide an interface to the underlying ODBC driver. Okay...feel free to deflect the minced oaths at MS's SQL Server ODBC driver then. :) The main problem came with queries like cursor.execute( SELECT a, b, c FROM table_x WHERE providerid = ? AND a IN ( SELECT z FROM table_y WHERE accountid = ? ), (providerid, accountid) ) The accountid = ? in the sub-query triggers some inability in some layer to determine what datatype it should be converted to, so it raises a FrustrateTim exception :) -tkc -- http://mail.python.org/mailman/listinfo/python-list
Emulate a printf() C-statement in Python???
I'm trying emulate a printf() c statement that does, for example char* name=Chris; int age=30; printf(My name is %s, name); printf(My name is %s and I am %d years old., %s, %d); In other words, printf() has a variable arguement list the we all know. I'm trying to do this in Python... class MyPrintf(object): # blah, blah def myprintf(object, *arg): # Here I'll have to know I NEED 2 arguments in format string arg[0] print arg[0] % (arg[1], arg[2]) name=Chris age=30 printf=MyPrintf() printf.myPrintf((My name is %s and I am %d years old., name, age) will of course print... My name is Chris and I am 42 years old. But printf.myPrintf((My name is %s., name) of course gives Index error: list index out of range How can I generalize the print call in the myprintf() function to do this? print arg[0] % (arg[1]) print arg[0] % (arg[1], arg[2]) print arg[0] % (arg[1], ..., arg[n]) -- --- Remove XSPAM -- http://mail.python.org/mailman/listinfo/python-list
Re: Do deep inheritance trees degrade efficiency?
On Thu, Mar 19, 2009 at 2:54 AM, Christian Heimes li...@cheimes.de wrote: Chris Rebert wrote: There's no effect on attribute read-writes as they all take place within the single __dict__ of the instance. As for method lookup, it doesn't add an indirection per se, but rather the list of classes to look thru to find a method gets longer, making base-class method lookups slower. IIRC, a typical method lookup does something like the following pseudocode: for klass in the_object.__mro__: if method_name in klass.__dict__: return klass.__dict__[method_name] raise AttributeError # no such attribute Your assumption is no longer true. Starting with Python 2.6 and 3.0 the lookup of attributes is cached. You can find detailed information by searching for VERSION_TAG in the source code. Very interesting. Now that's a smart optimization; sounds a bit similar to what V8 does for JavaScript. Cheers, Chris -- I have a blog: http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
ANN: eGenix mxODBC Connect 1.0.1 - Python Database Interface
ANNOUNCING eGenix.com mxODBC Connect Python Database Interface Version 1.0.1 Our new client-server product for connecting Python applications to relational databases - from all major platforms This announcement is also available on our web-site for online reading: http://www.egenix.com/company/news/eGenix-mxODBC-Connect-1.0.1-GA.html INTRODUCTION The mxODBC Connect Database Interface for Python allows users to easily connect Python applications to all major databases on the market today in a highly portable and convenient way. Unlike our mxODBC Python extension, mxODBC Connect is designed as client-server application, so you no longer need to find production quality ODBC drivers for all the platforms you target with your Python application. Instead you use an easy to install Python client library which connects directly to the mxODBC Connect database server over the network. This makes mxODBC Connect the ideal basis for writing cross-platform database programs and utilities in Python, especially if you run applications that need to communicate with databases such as MS SQL Server and MS Access, Oracle Database, IBM DB2 and Informix, Sybase ASE and Sybase Anywhere, MySQL, PostgreSQL, SAP MaxDB and many more, that run on Windows or Linux machines. By removing the need to install and configure ODBC drivers on the client side, mxODBC Connect greatly simplifies setup and configuration of database driven client applications, while at the same time making the network communication between client and database server more efficient and more secure. For more information, please see the product page: http://www.egenix.com/products/python/mxODBCConnect/ NEWS mxODBC Connect 1.0.1 is a patch-level release of our new mxODBC Connect product. * More Robust We have made the client and server more robust in case of communication failures. Even if the client applications fail to shutdown the server connection before exiting, the server will free up resources used by the client on the server side and rollback transactions as necessary. * More Platform Support With the 1.0.1 release we are also providing much better platform support for the mxODBC Connect Client: we have fixed a problem in 1.0.0 that prevented the installation of the pre-built clients on non-Linux systems. The mxODBC Connect Client can now be installed on most platforms supported by Python, since it is written in a platform independent, portable way. The pre-built archives also make it possible to integrate the clients into build system such as buildout (used in Zope and Plone) or other distutils-based deployment systems. * Ideal for Building Bridges As a result, connecting from e.g. Mac OS X to an SQL Server database has never been easier. You can even keep the data sources you already have configured on your Windows machine and connect to them as if your application were running on the database server itself. UPGRADING You are encouraged to upgrade to this latest mxODBC Connect release. When upgrading, please always upgrade both the server and the client installations to the same version - even for patch level releases. Customers who have purchased mxODBC Connect 1.0 licenses can download and upgrade their existing installations without having to purchase new licenses or upgrades. The licenses will continue to work with version 1.0.1. Users of our stand-alone mxODBC product will have to purchase new licenses from our online shop in order to use mxODBC Connect. You can request 30-day evaluation licenses by visiting our web-site or writing to sa...@egenix.com, stating your name (or the name of the company) and the number of eval licenses that you need. http://www.egenix.com/products/python/mxODBCConnect/#Evaluation DOWNLOADS The download archives as well as instructions for installation and configuration of the product can be found on the product page: http://www.egenix.com/products/python/mxODBCConnect/ Evaluation licenses for the server part are available free of charge: http://www.egenix.com/products/python/mxODBCConnect/#Evaluation The client part of mxODBC Connect is always free of charge. ___ SUPPORT Commercial support for this product is available from eGenix.com. Please see http://www.egenix.com/services/support/ for details about our support offerings. Enjoy, -- Marc-Andre Lemburg eGenix.com Professional Python Services directly from the Source (#1, Mar 19 2009)
Re: Do deep inheritance trees degrade efficiency?
Anthra Norell wrote: Would anyone who knows the inner workings volunteer to clarify whether or not every additional derivation of a class hierarchy adds an indirection to the base class's method calls and attribute read-writes. More potential search layers rather than pointer indirection. But I doubt this is a bottleneck in very many programs. So I would more concern myself first with quickly writing correct code. tjr -- http://mail.python.org/mailman/listinfo/python-list
Re: Emulate a printf() C-statement in Python???
On Thu, Mar 19, 2009 at 5:43 AM, Mr. Z no...@xspambellsouth.net wrote: I'm trying emulate a printf() c statement that does, for example char* name=Chris; int age=30; printf(My name is %s, name); printf(My name is %s and I am %d years old., %s, %d); In other words, printf() has a variable arguement list the we all know. I'm trying to do this in Python... class MyPrintf(object): # blah, blah def myprintf(object, *arg): # Here I'll have to know I NEED 2 arguments in format string arg[0] print arg[0] % (arg[1], arg[2]) name=Chris age=30 printf=MyPrintf() printf.myPrintf((My name is %s and I am %d years old., name, age) will of course print... My name is Chris and I am 42 years old. But printf.myPrintf((My name is %s., name) of course gives Index error: list index out of range How can I generalize the print call in the myprintf() function to do this? print arg[0] % (arg[1]) print arg[0] % (arg[1], arg[2]) print arg[0] % (arg[1], ..., arg[n]) def printf(format, *args): print format % args Although I fail to see the point in doing this. All you're doing is trading the use of the % operator for a function call. Cheers, Chris -- I have a blog: http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: python equivalent of java technologies
Hi Well zope has quite a few of these out of the box and have been around for a bit longer than some of the java options. Specifically persistence (ZODB persistence in zope is pretty much completely autmomatic) you can inplement web services with it (xmlrpc out of the box, though I assume you mean soap) zope encompasses security/ and authentication and can easily be integrated with a range of single signon environments. there are a range of scheduling services in to, but which is most like quartz I am not sure about. zope does support distributed transactions, but I not XA , but is ACID. In general there are a heap of interfaces for python do different message queues/buses, take you pick of you favourite platform. Not sure about reporting that is equivalent to jasper. T On Mar 19, 3:14 am, markolopa marko.lopa...@gmail.com wrote: Hello, When comparing python and java with a colleague who is fan of java, she challenged me to find in python the equivalent to the following technologies. Could you please help telling if we have something equivalent in python or not and how they compare to the java solutions? - persistance framework (~hibernate) - transational monitor (distributed transaction), XA compliance (message system, DB) (http://en.wikipedia.org/wiki/X/Open_XA) - web openess sur le web (web service) - RIA and web deployable graphic library - scheduling (quartz) - secutity (PKI, single sign-on...) - reporting (Jasper) Thanks a lot! Marko -- http://mail.python.org/mailman/listinfo/python-list
Python-URL! - weekly Python news and links (Mar 19)
QOTW: In that case I fear Python will be far too simple ... You've been programming for way too long ... - Steve Holden http://groups.google.com/group/comp.lang.python/msg/b8027713e674ef9d Having a function called after the constructor/__init__ is done: http://groups.google.com/group/comp.lang.python/browse_thread/thread/b9bb9d101e0cba4f/ How to add months to a date? http://groups.google.com/group/comp.lang.python/browse_thread/thread/13f3d0296128592a/ Processing a binary file in blocks of fixed size: http://groups.google.com/group/comp.lang.python/browse_thread/thread/e22b468d8ef4dd78/ It's hard to find the in keyword in the Python documentation: http://groups.google.com/group/comp.lang.python/browse_thread/thread/b28446a0c51de9fe/ Proposed format specifier for a thousands separator http://groups.google.com/group/comp.lang.python/browse_thread/thread/3a37546abd506626/ How to make ElementTree always return Unicode texts: http://groups.google.com/group/comp.lang.python/browse_thread/thread/31c996da94c26714/ Class- and instance-attributes with the same name may be confusing sometimes: http://groups.google.com/group/comp.lang.python/browse_thread/thread/e840cd0f5e37a26a/ The future of PyPy: http://groups.google.com/group/comp.lang.python/browse_thread/thread/641a8f8c34781e13/ Everything Python-related you want is probably one or two clicks away in these pages: Python.org's Python Language Website is the traditional center of Pythonia http://www.python.org Notice especially the master FAQ http://www.python.org/doc/FAQ.html PythonWare complements the digest you're reading with the marvelous daily python url http://www.pythonware.com/daily Just beginning with Python? This page is a great place to start: http://wiki.python.org/moin/BeginnersGuide/Programmers The Python Papers aims to publish the efforts of Python enthusiats: http://pythonpapers.org/ The Python Magazine is a technical monthly devoted to Python: http://pythonmagazine.com Readers have recommended the Planet sites: http://planetpython.org http://planet.python.org comp.lang.python.announce announces new Python software. Be sure to scan this newsgroup weekly. http://groups.google.com/group/comp.lang.python.announce/topics Python411 indexes podcasts ... to help people learn Python ... Updates appear more-than-weekly: http://www.awaretek.com/python/index.html The Python Package Index catalogues packages. http://www.python.org/pypi/ The somewhat older Vaults of Parnassus ambitiously collects references to all sorts of Python resources. http://www.vex.net/~x/parnassus/ Much of Python's real work takes place on Special-Interest Group mailing lists http://www.python.org/sigs/ Python Success Stories--from air-traffic control to on-line match-making--can inspire you or decision-makers to whom you're subject with a vision of what the language makes practical. http://www.pythonology.com/success The Python Software Foundation (PSF) has replaced the Python Consortium as an independent nexus of activity. It has official responsibility for Python's development and maintenance. http://www.python.org/psf/ Among the ways you can support PSF is with a donation. http://www.python.org/psf/donations/ The Summary of Python Tracker Issues is an automatically generated report summarizing new bugs, closed ones, and patch submissions. http://search.gmane.org/?author=status%40bugs.python.orggroup=gmane.comp.python.develsort=date Although unmaintained since 2002, the Cetus collection of Python hyperlinks retains a few gems. http://www.cetus-links.org/oo_python.html Python FAQTS http://python.faqts.com/ The Cookbook is a collaborative effort to capture useful and interesting recipes. http://code.activestate.com/recipes/langs/python/ Many Python conferences around the world are in preparation. Watch this space for links to them. Among several Python-oriented RSS/RDF feeds available, see: http://www.python.org/channews.rdf For more, see: http://www.syndic8.com/feedlist.php?ShowMatch=pythonShowStatus=all The old Python To-Do List now lives principally in a SourceForge reincarnation. http://sourceforge.net/tracker/?atid=355470group_id=5470func=browse http://www.python.org/dev/peps/pep-0042/ del.icio.us presents an intriguing approach to reference commentary. It already aggregates quite a bit of Python intelligence. http://del.icio.us/tag/python *Py: the Journal of
Re: Emulate a printf() C-statement in Python???
On Thu, Mar 19, 2009 at 2:43 PM, Mr. Z no...@xspambellsouth.net wrote: I'm trying emulate a printf() c statement that does, for example char* name=Chris; int age=30; printf(My name is %s, name); printf(My name is %s and I am %d years old., %s, %d); In other words, printf() has a variable arguement list the we all know. I'm trying to do this in Python... class MyPrintf(object): # blah, blah def myprintf(object, *arg): # Here I'll have to know I NEED 2 arguments in format string arg[0] print arg[0] % (arg[1], arg[2]) Note: you can, of course, use any name for the instance variable in methods, but 'self' is considered a de-facto standard, not 'object'. Besides, you're overriding builtin which is considered a bad practice. name=Chris age=30 printf=MyPrintf() printf.myPrintf((My name is %s and I am %d years old., name, age) will of course print... My name is Chris and I am 42 years old. But printf.myPrintf((My name is %s., name) of course gives Index error: list index out of range How can I generalize the print call in the myprintf() function to do this? print arg[0] % (arg[1]) print arg[0] % (arg[1], arg[2]) print arg[0] % (arg[1], ..., arg[n]) It's quite simple: def printf(fmt, *args): print fmt % args -- --- Remove XSPAM -- http://mail.python.org/mailman/listinfo/python-list -- Wbr, Andrii V. Mishkovskyi. He's got a heart of a little child, and he keeps it in a jar on his desk. -- http://mail.python.org/mailman/listinfo/python-list
Re: Do deep inheritance trees degrade efficiency?
Chris Rebert a écrit : On Wed, Mar 18, 2009 at 6:09 AM, Anthra Norell anthra.nor...@bluewin.ch wrote: Would anyone who knows the inner workings volunteer to clarify whether or not every additional derivation of a class hierarchy adds an indirection to the base class's method calls and attribute read-writes. In C++, I suppose, a three-level inheritance would resolve into something like *(*(*(*(base_class_method (). There's no effect on attribute read-writes as they all take place within the single __dict__ of the instance. Except when: - the attribute is a computed one (property or other descriptor) - (for read access) the attribute is not set in the instance's dict. As for method lookup, it doesn't make much difference - the very same lookup rules apply, and it's the descriptor protocol (as implemented by the 'function' type) that takes care of returning a method object (mostly a partial application of the function to the instance or class) when appropriate. (snip) However, you shouldn't really worry about the inefficiency of a deep inheritance tree as Python is probably not the right tool for the job if one have such efficiency concerns. (snip) [Note: I'm purposefully ignoring the fact that methods and attributes are in reality looked up in the exact same way for simplicity/clarity.] Ah, ok - then please don't take the above remarks as a personal offense !-) (still posting this since it might be of interest to the OP or someone else). -- http://mail.python.org/mailman/listinfo/python-list
Re: Roulette wheel
En Thu, 19 Mar 2009 08:06:35 -0200, mattia ger...@gmail.com escribió: OK, understood. Now, as a general rule, is it correct to say: - use generator expression when I just need to iterate over the list or call a function that involve an iterator (e.g. sum) and get the result, so the list is not necessary anymore - use list comprehensions when I actually have to use the list (e.g. I need to swap some values or I need to use sorted() etc.) Am I right? Yes, at least that's how I use them: a generator expression when the elements are consumed one by one in the same moment, and a list comprehension when I actually want the list as a whole. (Note that sorted() has to return a new list anyway, its argument may be a gen.expr. but sorted() starts by making a list out of it; you may be thinking of the list.sort() method) -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Re: Style formating of multiline query, advise
someone wrote: Also, for SQL, (A) why are you using nested joins?, and inner select produce smaller set which is then joined with other table, kind a optimization Did you time it? I've done some kind of a optimization that slowed queries by tenfold, because postgres didn't need my advice, and knew better. RDBMS performance is non-intuitive, really. If you're using mysql, YMMV, because its optimizer is not as good. Yes, my original question was about formatting. It's not original query (only a part). Try this: http://www.dpriver.com/pp/sqlformat.htm My 2c: I use textwrap.dedent to strip leading spaces from every line. -- http://mail.python.org/mailman/listinfo/python-list
Re: Uploading a file using POST
On Mar 19, 7:20 am, Justin Ezequiel justin.mailingli...@gmail.com
wrote:
On Mar 19, 8:50 am, Thomas Robitaille thomas.robitai...@gmail.com
wrote:
I am trying to upload a binary file (a tar.gz file to be exact) to a
web server using POST, from within a python script.
What I would like is essentially the equivalent of
form name='proceedings' method='post' action='www.whatever.com'
enctype=multipart/form-data
input name=userfile type=file
/form
have you seenhttp://code.activestate.com/recipes/146306/
or you can use pycurl
import pycurl
c = pycurl.Curl()
c.setopt(pycurl.URL, http://www.whatever.com;)
c.setopt(pycurl.POST, 1)
filepath = /path/of/file
filename = filename
c.setopt(pycurl.HTTPPOST, [('userfile', (pycurl.FORM_FILE, file_path,
pycurl.FORM_FILENAME, filename))])
c.perform()
read pycurl doc for more details. http://pycurl.sourceforge.net/doc/pycurl.html
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Re: Emulate a printf() C-statement in Python???
On Mar 19, 11:43 pm, Mr. Z no...@xspambellsouth.net wrote: I'm trying emulate a printf() c statement that does, for example char* name=Chris; int age=30; printf(My name is %s, name); printf(My name is %s and I am %d years old., %s, %d); In other words, printf() has a variable arguement list the we all know. I'm trying to do this in Python... | def printf(fmt, *args): | ...import sys | ...sys.stdout.write(fmt % args) | ... | printf(It's a %s %s parrot\n, 'Norwegian', 'blue') | It's a Norwegian blue parrot | HTH, John -- http://mail.python.org/mailman/listinfo/python-list
Re: Emulate a printf() C-statement in Python???
Mr. Z wrote: I'm trying emulate a printf() c statement that does, for example char* name=Chris; int age=30; printf(My name is %s, name); printf(My name is %s and I am %d years old., %s, %d); In other words, printf() has a variable arguement list the we all know. I'm trying to do this in Python... class MyPrintf(object): # blah, blah def myprintf(object, *arg): # Here I'll have to know I NEED 2 arguments in format string arg[0] print arg[0] % (arg[1], arg[2]) No you don't: in Python, the % operator on strings expects a tuple as second operand, and args is already a tuple. So: print args[0] % arhgs[1:] will do what you want. Some stylistic issues: - You don't have to put everything in a class in Python. Your myprintf looks a lot like a function to me, so you'll probably want to define it as such. - Don't use object as the first parameter to methods! object is the top-level class for the whole class hierarchy, so you certainly don't want to obscure it with a variable. For methods, use the traditional self as first parameter. - In your function myprintf, the format string seems to be a required argument. If it is, you might want to define as such too: def myprintf(format_string, *args): print format_string % args So now, as you can see, redefining printf in Python is not really interesting... HTH anyway. - Eric - -- http://mail.python.org/mailman/listinfo/python-list
Re: Emulate a printf() C-statement in Python???
On Mar 19, 11:52 pm, Chris Rebert c...@rebertia.com wrote: On Thu, Mar 19, 2009 at 5:43 AM, Mr. Z no...@xspambellsouth.net wrote: I'm trying emulate a printf() c statement that does, for example char* name=Chris; int age=30; printf(My name is %s, name); printf(My name is %s and I am %d years old., %s, %d); In other words, printf() has a variable arguement list the we all know. I'm trying to do this in Python... class MyPrintf(object): # blah, blah def myprintf(object, *arg): # Here I'll have to know I NEED 2 arguments in format string arg[0] print arg[0] % (arg[1], arg[2]) name=Chris age=30 printf=MyPrintf() printf.myPrintf((My name is %s and I am %d years old., name, age) will of course print... My name is Chris and I am 42 years old. But printf.myPrintf((My name is %s., name) of course gives Index error: list index out of range How can I generalize the print call in the myprintf() function to do this? print arg[0] % (arg[1]) print arg[0] % (arg[1], arg[2]) print arg[0] % (arg[1], ..., arg[n]) def printf(format, *args): print format % args The OP asked for an emulation of printf(), which doesn't have softspacing and other party tricks. Although I fail to see the point in doing this. All you're doing is trading the use of the % operator for a function call. It is one of those things that it is good to know, perhaps not so good to practice ... somewhat akin to the English definition of a Scots gentleman: A man who can play the bagpipes but doesn't. Cheers, John -- http://mail.python.org/mailman/listinfo/python-list
Python benchmarks comparing 32-bit to 64-bit performance
Are there any benchmarks (pystones or other) that compare a 32-bit and 64-bit versions of Python? Ideally I'm looking for a benchmark comparing recent Python releases (2.6.x, 3.x) on an Intel platform. I'm specifically interested in areas of the Python language where a 64-bit implementation is surprisingly faster or slower than its 32-bit equivalent. Thank you, Malcolm -- http://mail.python.org/mailman/listinfo/python-list
Preferred syntax for the docstrings
What's the preferred style to document code in python? I usually do something like this: === def somefunction(arg1, arg2, out = sys.stdout): This function does blahblablha with the string arg1, using the tuple of ints arg2 as the control sequence, and prints the result to out (defaults to sys.stdout) === That seems sub-optimal, I can't rapidly see what are you expecting from the arguments or the return value. I've seen some docstrings with the style === def somefunction(arg1, ar2, out = sys.stdout): brief description, possibly involving some symbolarg1, some symbol arg2 and some symbol arg3 some symbol arg1: string, some description ... === I guess there are several languages for writing the docstring. The question is, which is the preferred one in python, and where can I learn the syntax? (the one that python documentation viewers understand better? the one used by the stdlib?) How should/in what order should I write the docs? (brief description, argument types, return type, followed perhaps by some doctests). -- Luis Zarrabeitia Facultad de Matemática y Computación, UH http://profesores.matcom.uh.cu/~kyrie Participe en Universidad 2010, del 8 al 12 de febrero de 2010 La Habana, Cuba http://www.universidad2010.cu -- http://mail.python.org/mailman/listinfo/python-list
Re: Emulate a printf() C-statement in Python???
On Thu, Mar 19, 2009 at 6:13 AM, John Machin sjmac...@lexicon.net wrote: On Mar 19, 11:52 pm, Chris Rebert c...@rebertia.com wrote: On Thu, Mar 19, 2009 at 5:43 AM, Mr. Z no...@xspambellsouth.net wrote: I'm trying emulate a printf() c statement that does, for example char* name=Chris; int age=30; printf(My name is %s, name); printf(My name is %s and I am %d years old., %s, %d); In other words, printf() has a variable arguement list the we all know. I'm trying to do this in Python... class MyPrintf(object): # blah, blah def myprintf(object, *arg): # Here I'll have to know I NEED 2 arguments in format string arg[0] print arg[0] % (arg[1], arg[2]) name=Chris age=30 printf=MyPrintf() printf.myPrintf((My name is %s and I am %d years old., name, age) will of course print... My name is Chris and I am 42 years old. snip def printf(format, *args): print format % args The OP asked for an emulation of printf(), which doesn't have softspacing and other party tricks. Well, his implementation had the same issues, so I assumed he was going for something merely somewhat printf()-like rather than exactly the same. Though I suppose you might as well go all the way if you're doing something impractical like this. :) Cheers, Chris -- I have a blog: http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: Preferred syntax for the docstrings
On Thu, Mar 19, 2009 at 6:26 AM, Luis Zarrabeitia ky...@uh.cu wrote: What's the preferred style to document code in python? I usually do something like this: === def somefunction(arg1, arg2, out = sys.stdout): This function does blahblablha with the string arg1, using the tuple of ints arg2 as the control sequence, and prints the result to out (defaults to sys.stdout) === That seems sub-optimal, I can't rapidly see what are you expecting from the arguments or the return value. I've seen some docstrings with the style === def somefunction(arg1, ar2, out = sys.stdout): brief description, possibly involving some symbolarg1, some symbol arg2 and some symbol arg3 some symbol arg1: string, some description ... === I guess there are several languages for writing the docstring. The question is, which is the preferred one in python, and where can I learn the syntax? (the one that python documentation viewers understand better? the one used by the stdlib?) How should/in what order should I write the docs? (brief description, argument types, return type, followed perhaps by some doctests). It's pretty subjective based on which documentation generator you use (or if you don't use one at all, just your personal style), but personally I'd recommend reStructuredText and Sphinx (http://sphinx.pocoo.org/) since they're used for the std lib's very spiffy new docs. See the Sphinx homepage for how to learn the syntax. Cheers, Chris -- I have a blog: http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: How complex is complex?
[posted and e-mailed] In article 033514d1-e0e9-4a1c-bca0-846781f0d...@w35g2000prg.googlegroups.com, Kottiyath n.kottiy...@gmail.com wrote: On Mar 19, 11:29=A0am, Daniel Fetchinson fetchin...@googlemail.com wrote: Once every nuanced detail has been carefully weighed in and a consensus has been reached among the Supreme Python Language Commission chamber of the PSF the appropriate answer will be mailed back to you. Now you should be able to open up your favorite editor and hack away knowing full well that nobody and nothing can stop you, ever! I understand that my question was foolish, even for a newbie. I will not ask any more such questions in the future. No! Your question was *not* foolish, it was in fact a very good question; Daniel was just making a joke in somewhat dubious taste. (Not in such poor taste that Daniel should apologize, but I'm guessing that English is not your primary language, so it can be difficult to identify jokes here. Because the name Python is derived from the comedy TV show Monty Python, stupid jokes are common in the Python community.) -- Aahz (a...@pythoncraft.com) * http://www.pythoncraft.com/ Programming language design is not a rational science. Most reasoning about it is at best rationalization of gut feelings, and at worst plain wrong. --GvR, python-ideas, 2009-3-1 -- http://mail.python.org/mailman/listinfo/python-list
Re: Preferred syntax for the docstrings
Quoting Chris Rebert c...@rebertia.com: It's pretty subjective based on which documentation generator you use (or if you don't use one at all, just your personal style), but personally I'd recommend reStructuredText and Sphinx (http://sphinx.pocoo.org/) since they're used for the std lib's very spiffy new docs. See the Sphinx homepage for how to learn the syntax. Cheers, Chris That was quick! Thanks! Opening the page now. -- Luis Zarrabeitia Facultad de Matemática y Computación, UH http://profesores.matcom.uh.cu/~kyrie Participe en Universidad 2010, del 8 al 12 de febrero de 2010 La Habana, Cuba http://www.universidad2010.cu -- http://mail.python.org/mailman/listinfo/python-list
Re: Do deep inheritance trees degrade efficiency?
Bruno Desthuilliers wrote: Chris Rebert a écrit : On Wed, Mar 18, 2009 at 6:09 AM, Anthra Norell anthra.nor...@bluewin.ch wrote: Would anyone who knows the inner workings volunteer to clarify whether or not every additional derivation of a class hierarchy adds an indirection to the base class's method calls and attribute read-writes. In C++, I suppose, a three-level inheritance would resolve into something like *(*(*(*(base_class_method (). There's no effect on attribute read-writes as they all take place within the single __dict__ of the instance. Except when: - the attribute is a computed one (property or other descriptor) - (for read access) the attribute is not set in the instance's dict. As for method lookup, it doesn't make much difference - the very same lookup rules apply, and it's the descriptor protocol (as implemented by the 'function' type) that takes care of returning a method object (mostly a partial application of the function to the instance or class) when appropriate. (snip) However, you shouldn't really worry about the inefficiency of a deep inheritance tree as Python is probably not the right tool for the job if one have such efficiency concerns. (snip) [Note: I'm purposefully ignoring the fact that methods and attributes are in reality looked up in the exact same way for simplicity/clarity.] Ah, ok - then please don't take the above remarks as a personal offense !-) (still posting this since it might be of interest to the OP or someone else). -- http://mail.python.org/mailman/listinfo/python-list The OP (that's me) thankfully acknowledges all contributions. The upshot of it all seems to be that there are countless ways for a compiler or interpreter to handle access through class hierarchies. I did a very crude test myself, like this: class A: def do (self): pass class B (A): pass class C (B): pass class D (C): pass class E (D): pass # Got to stop somewhere a = A () for i in xrange (100): a.do () 11 seconds e = E () for i in xrange (100): e.do () 14 seconds No significant difference indeed ! Frederic -- http://mail.python.org/mailman/listinfo/python-list
Re: set_process_affinity_mask problem - Python 2.5 gcc 4.3.2 (Ubuntu 4.3.2-1ubuntu12)
In article mailman.1499.1236566959.11746.python-l...@python.org, Isaac Gouy igo...@yahoo.com wrote: Now I've upgraded from Ubuntu 8.04 to Ubuntu 8.10 (from gcc 4.2.3 to gcc 4.3.2) and set_process_affinity_mask seems to fail on the x86 Ubuntu install. It still works fine, after upgrade, on the x64 Ubuntu install. [...] Please suggest what I can do to debug / fix this problem. Search the Ubuntu bugs first, then ask on an Ubuntu mailing list. My impression is that 8.10 is a bit half-baked -- I'm rather annoyed that the feature save session on logout is completely b0rked, but it's not so annoying that I'll downgrade. -- Aahz (a...@pythoncraft.com) * http://www.pythoncraft.com/ Programming language design is not a rational science. Most reasoning about it is at best rationalization of gut feelings, and at worst plain wrong. --GvR, python-ideas, 2009-3-1 -- http://mail.python.org/mailman/listinfo/python-list
Re: Emulate a printf() C-statement in Python???
Andrii V. Mishkovskyi misho...@gmail.com wrote in message news:mailman.2185.1237467269.11746.python-l...@python.org... On Thu, Mar 19, 2009 at 2:43 PM, Mr. Z no...@xspambellsouth.net wrote: I'm trying emulate a printf() c statement that does, for example char* name=Chris; int age=30; printf(My name is %s, name); printf(My name is %s and I am %d years old., %s, %d); In other words, printf() has a variable arguement list the we all know. I'm trying to do this in Python... class MyPrintf(object): # blah, blah def myprintf(object, *arg): # Here I'll have to know I NEED 2 arguments in format string arg[0] print arg[0] % (arg[1], arg[2]) Note: you can, of course, use any name for the instance variable in methods, but 'self' is considered a de-facto standard, not 'object'. Besides, you're overriding builtin which is considered a bad practice. name=Chris age=30 printf=MyPrintf() printf.myPrintf((My name is %s and I am %d years old., name, age) will of course print... My name is Chris and I am 42 years old. But printf.myPrintf((My name is %s., name) of course gives Index error: list index out of range How can I generalize the print call in the myprintf() function to do this? print arg[0] % (arg[1]) print arg[0] % (arg[1], arg[2]) print arg[0] % (arg[1], ..., arg[n]) It's quite simple: def printf(fmt, *args): print fmt % args -- --- Remove XSPAM -- http://mail.python.org/mailman/listinfo/python-list Too simple, I love it! -- Wbr, Andrii V. Mishkovskyi. He's got a heart of a little child, and he keeps it in a jar on his desk. -- http://mail.python.org/mailman/listinfo/python-list
Re: How to do this in Python? - A gotcha
On Mar 18, 6:06 pm, Jim Garrison j...@acm.org wrote: S Arrowsmith wrote: Jim Garrison j...@acm.org wrote: It's a shame the iter(o,sentinel) builtin does the comparison itself, instead of being defined as iter(callable,callable) where the second argument implements the termination test and returns a boolean. This would seem to add much more generality... is it worthy of a PEP? class sentinel: def __eq__(self, other): return termination_test() for x in iter(callable, sentinel()): ... Writing a sensible sentinel.__init__ is left as an exercise If I understand correctly, this pattern allows me to create an object (instance of class sentinel) that implements whatever equality semantics I need to effect loop termination. In the case in point, then, I end up with class sentinel: def __eq__(self,other): return other=='' or other==b'' with open(filename, rb) as f: for buf in iter(lambda: f.read(1000), sentinel())): do_something(buf) i.e. sentinel is really object that compares equal to both '' and b''. While I appreciate how this works, I think the introduction of a whole new class is a bit of overkill for what should be expressible in iter()- Hide quoted text - - Show quoted text - In the specific case it should not be needed to create a class, because at least with python 2.6: b'' == '' True u'' == '' True so you should be able to do: with open(filename, rb) as f: for buf in iter(lambda: f.read(1000), ): do_something(buf) Ciao -- FB -- http://mail.python.org/mailman/listinfo/python-list
Re: Is python worth learning as a second language?
In article 49b5196b$0$3514$426a7...@news.free.fr, Bruno Desthuilliers bruno.42.desthuilli...@websiteburo.invalid wrote: Grant Edwards a écrit : Knowing C++ does tend to be a bit of a handicap, but I think any competent programmer could learn Python. +2 QOTW !-) Ditto! Although I suppose you could just go for the jugular and say that C++ is the BASIC of the 1990s. -- Aahz (a...@pythoncraft.com) * http://www.pythoncraft.com/ Programming language design is not a rational science. Most reasoning about it is at best rationalization of gut feelings, and at worst plain wrong. --GvR, python-ideas, 2009-3-1 -- http://mail.python.org/mailman/listinfo/python-list
Re: Is python worth learning as a second language?
In article 49b58b35$0$3548$426a7...@news.free.fr, Bruno Desthuilliers bdesth.quelquech...@free.quelquepart.fr wrote: Tomasz Rola a écrit : I may not be objective (tried Java, hated it after 6 years). Arf - only took me 6 months !-) That long? It only took me six minutes. -- Aahz (a...@pythoncraft.com) * http://www.pythoncraft.com/ Programming language design is not a rational science. Most reasoning about it is at best rationalization of gut feelings, and at worst plain wrong. --GvR, python-ideas, 2009-3-1 -- http://mail.python.org/mailman/listinfo/python-list
Re: supervisor 3.0a6 and Python2.6
George Trojan wrote: 1. Is supervisor still developed? I note that, although the information on the site is pretty old, there have been some respository checkins in Feb and March of this year: http://lists.supervisord.org/pipermail/supervisor-checkins/ -r -- http://mail.python.org/mailman/listinfo/python-list
can someone help me (again) stuck on ' hands on python'
#I adjusted the 2nd main function so i test what im trying to do can someone
point me in the right direction please
Exercise 2.3.3.1. ** Rename the example file locationsStub.py to be
locations.py, and complete the function printLocations, to print the index of
each location in the string s where target is located. For example,
printLocations('This is a dish', 'is') would go through the string 'This is a
dish' looking for the index of places where 'is' appears, and would return [2,
5, 11]. Similarly printLocations('This is a dish', 'h') would return [1, 13].
The program stub already uses the string method count. You will need to add
code using the more general form of find.
code
'''Exercise to complete printLocations as described below.
Create file locations.py.'''
def printLocations(target):
'''s is a string to search through, and target is the substring to look for.
Print each index where the target starts.
For example:
printLocations('Here, there, everywhere!', 'ere')
1
8
20
'''
def main():
phrase = 'Here, there, everywhere!'
print('Phrase:', phrase)
for target in ['ere', 'er', 'e', 'zx']:
print('finding:', target)
printLocations(phrase, target)
print('All done!')
main()
#i adjusted the main function helps me see the code as the program runs
def main():
phrase = 'Here, there, everywhere!'
print('Phrase:', phrase)
for target in ['ere', 'er', 'e', 'zx']:
print('finding:', target)
printLocations=(phrase, target)
print(printLocations,'locations :',phrase.find(target))
print('All done!')
main()
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Re: Is python worth learning as a second language?
The other day one of our developers said that he thought learning assembler language in college was a total waste of time. I can't disagree more. Even if assembler language is specific to one architecture, the principles that it teaches are universal and fundamental to all other programming languages. Besides, programming in assembler can be fun, in a sick sort of way... :-) -- http://mail.python.org/mailman/listinfo/python-list
Re: How to do this in Python? - A gotcha
bieff...@gmail.com wrote:
On Mar 18, 6:06 pm, Jim Garrison j...@acm.org wrote:
S Arrowsmith wrote:
Jim Garrison j...@acm.org wrote:
It's a shame the iter(o,sentinel) builtin does the
comparison itself, instead of being defined as iter(callable,callable)
where the second argument implements the termination test and returns a
boolean. This would seem to add much more generality... is
it worthy of a PEP?
class sentinel:
def __eq__(self, other):
return termination_test()
for x in iter(callable, sentinel()):
...
Writing a sensible sentinel.__init__ is left as an exercise
If I understand correctly, this pattern allows me to create
an object (instance of class sentinel) that implements whatever
equality semantics I need to effect loop termination. In the
case in point, then, I end up with
class sentinel:
def __eq__(self,other):
return other=='' or other==b''
with open(filename, rb) as f:
for buf in iter(lambda: f.read(1000), sentinel())):
do_something(buf)
i.e. sentinel is really object that compares equal to both ''
and b''. While I appreciate how this works, I think the
introduction of a whole new class is a bit of overkill for
what should be expressible in iter()- Hide quoted text -
- Show quoted text -
In the specific case it should not be needed to create a class,
because
at least with python 2.6:
b'' == ''
True
u'' == ''
True
Ah, you misunderstand the short-term expedient that 2.6 took.
Effectively, it simply said, bytes = str.
In 2.6:
str is bytes
True
in 3.X:
str is bytes
False
b'' == ''
False
type(b''), type('')
(class 'bytes', class 'str')
--Scott David Daniels
scott.dani...@acm.org
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Re: python equivalent of java technologies
On Thursday 19 March 2009 07:45:01 Jeremiah Dodds wrote: On Tue, Mar 17, 2009 at 8:32 PM, Armin feng.sh...@gmail.com wrote: You could tell her to try Jython. In that, you can just use the Java implementations. :) Plus, you have things in Jython that Java doesn't :D -- Armin Moradi -- http://mail.python.org/mailman/listinfo/python-list Exactly. Her challenges to find stuff have to do with the JVM, not Java the language. Python runs on the JVM. Indeed, afaik, Jython produces Java byte-code. -- Armin Moradi -- http://mail.python.org/mailman/listinfo/python-list
Re: supervisor 3.0a6 and Python2.6
Raymond Cote wrote: George Trojan wrote: 1. Is supervisor still developed? I note that, although the information on the site is pretty old, there have been some respository checkins in Feb and March of this year: http://lists.supervisord.org/pipermail/supervisor-checkins/ -r I found answers to both questions (the other one was: Is there a quick fix to the above behaviour?) - accidentally the same day, on March 17 there was a post on supervisor-users group: http://lists.supervisord.org/pipermail/supervisor-users/2009-March/000311.html. The answer by one of supervisor's developer led me to an interesting thread on python-dev: asyncore fixes in Python 2.6 broke Zope's version of medusa dated March 4: http://mail.python.org/pipermail/python-dev/2009-March/thread.html#86739 George -- http://mail.python.org/mailman/listinfo/python-list
DictReader and fieldnames
Is it possible to grab the fieldnames that the csv DictReader module automatically reads from the first line of the input file? Thanks, Ted To -- http://mail.python.org/mailman/listinfo/python-list
Re: mxODBC (was split problem if the delimiter is inside the text limiter)
On 2009-03-19 13:40, Tim Chase wrote:
DB-API 2.0 has cursor.executemany() to make this differentiation
at the API level. mxODBC will lift this requirement in the next
version, promised :-)
glad to hear...will executemany() take an arbitrary iterable? My
(albeit somewhat-antiquated) version balked at anything that wasn't a
list/tuple (don't remember off the top of my head which it was). For a
lot of my ETL work, it would be nice to pass a generator so I don't have
to keep huge datasets in memory.
cursor.executemany() is designed to work on bulk data. It allows
passing a whole chunk of data to the database in one go. It will
currently accept any sequence, but not an iterator. However, we may
add support for general iterators to the next version.
If you want to use a generator with mxODBC 3.0, you are probably
better off using e.g.
cmd = 'INSERT ... VALUES (?,?,?)'
for row in iterable:
cursor.execute(cmd, row)
Since you always use the same command object, this will trigger
an optimization in mxODBC whereby the prepare step for the command
is only applied once and the already prepared command then
reused for all subsequent executes.
(and don't get me started on mxODBC's failure to
determine the data-type for parameters in subqueries, raising exceptions
on perfectly valid queries/rant)
I'm not sure what you are referring to here. mxODBC can only provide
an interface to the underlying ODBC driver.
Okay...feel free to deflect the minced oaths at MS's SQL Server ODBC
driver then. :) The main problem came with queries like
cursor.execute(
SELECT a, b, c
FROM table_x
WHERE providerid = ?
AND a IN (
SELECT z
FROM table_y
WHERE accountid = ?
), (providerid, accountid)
)
The accountid = ? in the sub-query triggers some inability in some
layer to determine what datatype it should be converted to, so it raises
a FrustrateTim exception :)
Parameter binding markers are not always supported in all contexts.
The error that I get from the SQL Server ODBC driver for the above is:
mx.ODBC.Error.ProgrammingError: ('42000', 0, '[Microsoft][SQL Server Native
Client 10.0]Syntax error, permission violation, or other nonspecific error',
7498)
In such a case, you may have more luck by using mxODBC's
cursor.executedirect(). This uses a different mechanism for preparing
and binding the data to the command which basically moves the
process to the database server side.
--
Marc-Andre Lemburg
eGenix.com
Professional Python Services directly from the Source (#1, Mar 19 2009)
Python/Zope Consulting and Support ...http://www.egenix.com/
mxODBC.Zope.Database.Adapter ... http://zope.egenix.com/
mxODBC, mxDateTime, mxTextTools ...http://python.egenix.com/
::: Try our new mxODBC.Connect Python Database Interface for free !
eGenix.com Software, Skills and Services GmbH Pastor-Loeh-Str.48
D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
Registered at Amtsgericht Duesseldorf: HRB 46611
http://www.egenix.com/company/contact/
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Wordpress management from Python: do you know main bindings/modules to automate Wordpress blogging from .py software?
Hi, Everybody! I'm a Wordpress newbie but will have need to automate posts and would like to use Python for this purpose too: can you lead the way to this target? Many thanks in advance for your kind indications! ps some times ago, I heard about a Wordpress Python Library too but I do not know if it is maintained and where in case Warmest regards, Aldo -- http://mail.python.org/mailman/listinfo/python-list
Re: Preferred syntax for the docstrings
Luis Zarrabeitia wrote: What's the preferred style to document code in python? ... def somefunction(arg1, arg2, out = sys.stdout): This function does blahblablha with the string arg1, using the tuple of ints arg2 as the control sequence, and prints the result to out (defaults to sys.stdout) ... [or] ... def somefunction(arg1, ar2, out = sys.stdout): brief description, possibly involving some symbolarg1, some symbol arg2 and some symbol arg3 some symbol arg1: string, some description ... I guess there are several languages for writing the docstring. The question is, which is the preferred one in python, and where can I learn the syntax? (the one that python documentation viewers understand better? the one used by the stdlib?) How should/in what order should I write the docs? (brief description, argument types, return type, followed perhaps by some doctests). A fairly common style is to have the first line of the docstring summarize the function (without repeating the arglist), a blank line, and then more elaborating text. Some systems (notably Idle) will provide the arglist and that first line as a floating hint when using functions/methods interactively. Note how much of Python's own library provide help this way. Exploratory programming becomes much easier when you follow that rule. Try it, it is fun. go into Idle and type: def f(a, bc, defg): '''A trap: never use 'def' as an arg name. In which Doris gets her oats. ''' return 3 f( And at this point pause a second, the hint will appear. I use both this and print(a.b.__doc__) regularly for reminders of what I have once read. --Scott David Daniels scott.dani...@acm.org -- http://mail.python.org/mailman/listinfo/python-list
Re: How complex is complex?
On Mar 19, 4:39 am, Kottiyath n.kottiy...@gmail.com wrote: I understand that my question was foolish, even for a newbie. I will not ask any more such questions in the future. Gaaah! Your question was just fine, a good question on coding style. I wish more people would ask such questions so that bad habits could be avoided. The newbie posts that are annoying are the ones that: - are answered on page 1 of any tutorial (how do I get the second character of a string?) - are obvious homework assignments with no actual effort on the poster's part (how do I write a Python program to find the first 10 prime numbers?) - pontificate on what is wrong with Python, based on 2 hours' experience with the language (often titled What's wrong with Python, with content like Python sucks because it doesn't have a switch statement/has significant whitespace/doesn't check types of arguments/ isn't totally object-oriented like Java/doesn't have interfaces/...) - are so vague as to be just Usenet noise (titled Help me, with no content, or i need to write a program and don't know where to start can someone write it for me?) I think Daniel's joke was on the rest of us, who each had to chime in with our favorite dict processing algorithm. It *would* be good for you as a newbie to get an appreciation of the topics that were covered in these responses, though, especially the distinction between updating the dict in-place vs. creating a new dict. -- Paul -- http://mail.python.org/mailman/listinfo/python-list
Can I rely on...
Hi everybody, I just had a bit of a shiver for something I'm doing often in my code but that might be based on a wrong assumption on my part. Take the following code: pattern = aPattern compiledPatterns = [ ] compiledPatterns.append(re.compile(pattern)) if(re.compile(pattern) in compiledPatterns): print(The compiled pattern is stored.) As you can see I'm effectively assuming that every time re.compile() is called with the same input pattern it will return the exact same object rather than a second, identical, object. In interactive tests via python shell this seems to be the case but... can I rely on it - always- being the case? Or is it one of those implementation-specific issues? And what about any other function or class/method? Is there a way to discriminate between methods and functions that when invoked twice with the same arguments will return the same object and those that in the same circumstances will return two identical objects? If the answer is no, am I right to state the in the case portrayed above the only way to be safe is to use the following code instead? for item in compiledPatterns: if(item.pattern == pattern): -- http://mail.python.org/mailman/listinfo/python-list
Can I rely on...
Sorry for the double-post, the first one was sent by mistake before completion. Hi everybody, I just had a bit of a shiver for something I'm doing often in my code but that might be based on a wrong assumption on my part. Take the following code: pattern = aPattern compiledPatterns = [ ] compiledPatterns.append(re.compile(pattern)) if(re.compile(pattern) in compiledPatterns): print(The compiled pattern is stored.) As you can see I'm effectively assuming that every time re.compile() is called with the same input pattern it will return the exact same object rather than a second, identical, object. In interactive tests via python shell this seems to be the case but... can I rely on it - always- being the case? If the answer is no, am I right to state the in the case portrayed above the only way to be safe is to use the following code instead? for item in compiledPatterns: if(item.pattern == pattern): print(The compiled pattern is stored.) break And what about any other function or class/method? Is there a way to discriminate between methods and functions that when invoked twice with the same arguments will return the same object and those that in the same circumstances will return two identical objects? Or is it one of those implementation-specific issues? Manu -- http://mail.python.org/mailman/listinfo/python-list
converting pipe delimited file to fixed width
Hi,
I am trying to convert a | delimited file to fixed width by right
padding with spaces, Here is how I have written the program , just get
the feeling this can be done in a much better ( python functional )
way rather than the procedural code i have below . Any help
appreciated
#!/usr/bin/python
def rightFill(fillString, toLength, fillChar):
return fillString+''.join([fillChar for x in range(len
(fillString),toLength)])
fieldWidth=[ 14, 6, 18, 21, 21,4, 6 ];
file = open(/home/chatdi/input.csv, r);
lines = file.readlines()
file.close()
out = open( /home/chatdi/ouptut.csv, 'w')
for line in lines:
line = line[:-1]
index = 0
for token in line.split('|'):
paddedToken = rightFill(token, fieldWidth[index], ' ' )
out.write( paddedToken )
index = index + 1
out.write(\n)
--
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Re: Can I rely on...
Emanuele D'Arrigo wrote: Hi everybody, I just had a bit of a shiver for something I'm doing often in my code but that might be based on a wrong assumption on my part. Take the following code: pattern = aPattern compiledPatterns = [ ] compiledPatterns.append(re.compile(pattern)) if(re.compile(pattern) in compiledPatterns): print(The compiled pattern is stored.) You don't need parentheses in the 'if', or the 'print' in Python 2.x. As you can see I'm effectively assuming that every time re.compile() is called with the same input pattern it will return the exact same object rather than a second, identical, object. In interactive tests via python shell this seems to be the case but... can I rely on it - always- being the case? Or is it one of those implementation-specific issues? The re module has a cache of patterns, so if the pattern is already known then it'll return the existing compiled pattern. However, the cache has a limited size. In reality, no 2 pattern objects are equal. And what about any other function or class/method? Is there a way to discriminate between methods and functions that when invoked twice with the same arguments will return the same object and those that in the same circumstances will return two identical objects? If the answer is no, am I right to state the in the case portrayed above the only way to be safe is to use the following code instead? for item in compiledPatterns: if(item.pattern == pattern): This is the same as using 'in'. -- http://mail.python.org/mailman/listinfo/python-list
Re: Can I rely on...
Emanuele D'Arrigo wrote: [snip] If the answer is no, am I right to state the in the case portrayed above the only way to be safe is to use the following code instead? for item in compiledPatterns: if(item.pattern == pattern): print(The compiled pattern is stored.) break Correction to my last post: this isn't the same as using 'in'. It should work, but remember that it compares only the pattern and not any flags you might have used in the original re.compile(). -- http://mail.python.org/mailman/listinfo/python-list
Re: Can I rely on...
On Thu, 2009-03-19 at 08:42 -0700, Emanuele D'Arrigo wrote:
Hi everybody,
I just had a bit of a shiver for something I'm doing often in my code
but that might be based on a wrong assumption on my part. Take the
following code:
pattern = aPattern
compiledPatterns = [ ]
compiledPatterns.append(re.compile(pattern))
if(re.compile(pattern) in compiledPatterns):
print(The compiled pattern is stored.)
As you can see I'm effectively assuming that every time re.compile()
is called with the same input pattern it will return the exact same
object rather than a second, identical, object. In interactive tests
via python shell this seems to be the case but... can I rely on it -
always- being the case? Or is it one of those implementation-specific
issues?
And what about any other function or class/method? Is there a way to
discriminate between methods and functions that when invoked twice
with the same arguments will return the same object and those that in
the same circumstances will return two identical objects?
If the answer is no, am I right to state the in the case portrayed
above the only way to be safe is to use the following code instead?
for item in compiledPatterns:
if(item.pattern == pattern):
In general, no. You cannot rely on objects instantiated with the same
parameters to be equal. Eg.:
class N(object):
def __init__(self, foo):
self.foo = foo
a = N('m')
b = N('m')
a == b
False
If, however, the designer of the class implements it as such
(and documents it as well) then you can. E.g:
del N
class N(object):
def __init__(self, foo):
self.foo = foo
def __eq__(self, other):
return self.foo == other.foo
a = N('m')
b = N('m')
a == b
True
For functions/methods it really depends on the implementation. For
example, do we *really* want the following to always be true? Even
though we passed the same arguments?
import random
random.randint(0, 10) == random.randint(0, 10)
For the re module, unless it's documented that
re.compile(p) == re.compile(p)
is always true then you should not rely on it, because it's an
implementation detail that may change in the future.
--
http://mail.python.org/mailman/listinfo/python-list
Re: converting pipe delimited file to fixed width
digz wrote:
Hi,
I am trying to convert a | delimited file to fixed width by right
padding with spaces, Here is how I have written the program , just get
the feeling this can be done in a much better ( python functional )
way rather than the procedural code i have below . Any help
appreciated
#!/usr/bin/python
def rightFill(fillString, toLength, fillChar):
return fillString+''.join([fillChar for x in range(len
(fillString),toLength)])
fieldWidth=[ 14, 6, 18, 21, 21,4, 6 ];
file = open(/home/chatdi/input.csv, r);
lines = file.readlines()
file.close()
out = open( /home/chatdi/ouptut.csv, 'w')
for line in lines:
line = line[:-1]
index = 0
for token in line.split('|'):
paddedToken = rightFill(token, fieldWidth[index], ' ' )
out.write( paddedToken )
index = index + 1
out.write(\n)
Here's my version:
#!/usr/bin/python
field_widths = [14, 6, 18, 21, 21, 4, 6]
out = open(/home/chatdi/ouptut.csv, 'w')
for line in open(/home/chatdi/input.csv, r):
fields = line.rstrip().split('|')
padded_fields = [field.ljust(width) for field, width in zip(fields,
field_widths)]
out.write(.join(padded_fields) + \n)
out.close()
--
http://mail.python.org/mailman/listinfo/python-list
Re: Do deep inheritance trees degrade efficiency?
Terry Reedy wrote: Anthra Norell wrote: Would anyone who knows the inner workings volunteer to clarify whether or not every additional derivation of a class hierarchy adds an indirection to the base class's method calls and attribute read-writes. More potential search layers rather than pointer indirection. But I doubt this is a bottleneck in very many programs. So I would more concern myself first with quickly writing correct code. I should add that when object access time matters and the object is accessed repeatedly, a common solution is to bind it to a local name *once* and then access it via the local (which is the fastest way possible for CPython and, I expect, for other implementation). This works for all slower access methods. tjr -- http://mail.python.org/mailman/listinfo/python-list
Re: File Compare with difflib.context_diff
Here is the latest version of the code: currentdata_file = rC:\Users\Owner\Desktop\newdata.txt # the latest download from the clock lastdata_file = rC:\Users\Owner\Desktop\mydata.txt # the prior download from the clock output_file = rC:\Users\Owner\Desktop\out.txt # will hold delta clock data newdata = open(currentdata_file).read()[len(open(lastdata_file).read ()):] newdata2 = newdata.strip() file = open(output_file, 'w') file.write(newdata2) file.close() Do I need to close currentdata_file and lastdata_file ? Have not gotten the os.stat example to work yet... thanks for the help. -- http://mail.python.org/mailman/listinfo/python-list
Simple question about yyyy/mm/dd
Hi all, I need to receive in input a date represented by a string in the form /mm/dd (or reversed), then I need to assure that the date is = the current date and then split the dates in variables like year, month, day. Is there some module to do this quickly? -- http://mail.python.org/mailman/listinfo/python-list
Re: How complex is complex?
On Mar 19, 8:42 pm, Paul McGuire pt...@austin.rr.com wrote: On Mar 19, 4:39 am, Kottiyath n.kottiy...@gmail.com wrote: I understand that my question was foolish, even for a newbie. I will not ask any more such questions in the future. Gaaah! Your question was just fine, a good question on coding style. I wish more people would ask such questions so that bad habits could be avoided. The newbie posts that are annoying are the ones that: - are answered on page 1 of any tutorial (how do I get the second character of a string?) - are obvious homework assignments with no actual effort on the poster's part (how do I write a Python program to find the first 10 prime numbers?) - pontificate on what is wrong with Python, based on 2 hours' experience with the language (often titled What's wrong with Python, with content like Python sucks because it doesn't have a switch statement/has significant whitespace/doesn't check types of arguments/ isn't totally object-oriented like Java/doesn't have interfaces/...) - are so vague as to be just Usenet noise (titled Help me, with no content, or i need to write a program and don't know where to start can someone write it for me?) I think Daniel's joke was on the rest of us, who each had to chime in with our favorite dict processing algorithm. It *would* be good for you as a newbie to get an appreciation of the topics that were covered in these responses, though, especially the distinction between updating the dict in-place vs. creating a new dict. -- Paul Daniel, Sorry for misunderstanding your post. I hope I was not being passive-aggresive - (also because I found that the second mechanism I provided was quite horrible :-), so I was indeed being foolish there. ) Paul/Aahz, I did understand 2 things (1) When using map always consider that the function will be called everytime, so the hit on the performance is more. (2) The second mechanism and the first mechanism provides different solutions (new dict/same dict) both of which I did not think about at all. Also, thank you everyone for all the help. I have been following this thread for the last 4 months (when I started with python) and I have learned a lot. The amount of help provided here is amazing. p.s. - English is indeed not my first language :-) -- http://mail.python.org/mailman/listinfo/python-list
Re: How complex is complex?
On Mar 19, 9:33 pm, Kottiyath n.kottiy...@gmail.com wrote: On Mar 19, 8:42 pm, Paul McGuire pt...@austin.rr.com wrote: On Mar 19, 4:39 am, Kottiyath n.kottiy...@gmail.com wrote: I understand that my question was foolish, even for a newbie. I will not ask any more such questions in the future. Gaaah! Your question was just fine, a good question on coding style. I wish more people would ask such questions so that bad habits could be avoided. The newbie posts that are annoying are the ones that: - are answered on page 1 of any tutorial (how do I get the second character of a string?) - are obvious homework assignments with no actual effort on the poster's part (how do I write a Python program to find the first 10 prime numbers?) - pontificate on what is wrong with Python, based on 2 hours' experience with the language (often titled What's wrong with Python, with content like Python sucks because it doesn't have a switch statement/has significant whitespace/doesn't check types of arguments/ isn't totally object-oriented like Java/doesn't have interfaces/...) - are so vague as to be just Usenet noise (titled Help me, with no content, or i need to write a program and don't know where to start can someone write it for me?) I think Daniel's joke was on the rest of us, who each had to chime in with our favorite dict processing algorithm. It *would* be good for you as a newbie to get an appreciation of the topics that were covered in these responses, though, especially the distinction between updating the dict in-place vs. creating a new dict. -- Paul Daniel, Sorry for misunderstanding your post. I hope I was not being passive-aggresive - (also because I found that the second mechanism I provided was quite horrible :-), so I was indeed being foolish there. ) Paul/Aahz, I did understand 2 things (1) When using map always consider that the function will be called everytime, so the hit on the performance is more. (2) The second mechanism and the first mechanism provides different solutions (new dict/same dict) both of which I did not think about at all. Also, thank you everyone for all the help. I have been following this thread for the last 4 months (when I started with python) and I have learned a lot. The amount of help provided here is amazing. p.s. - English is indeed not my first language :-) Oops, Forgot to mention the biggest learning. Readability is better than brevity - Thanks to Rhodri. This was a question which was bugging me all the time. When I look at code, I am always envious when I see the same code written in much smaller number of lines. Now, I will force myself to ask the questions Rhodri proposed (esp: does it look uglier part) before deciding whether or not to go ahead with brevity. -- http://mail.python.org/mailman/listinfo/python-list
Re: Can I rely on...
Emanuele D'Arrigo wrote: Hi everybody, I just had a bit of a shiver for something I'm doing often in my code but that might be based on a wrong assumption on my part. Take the following code: pattern = aPattern compiledPatterns = [ ] compiledPatterns.append(re.compile(pattern)) if(re.compile(pattern) in compiledPatterns): Note that for this generally take time proportional to the length of the list. And as MRAB said, drop the parens. print(The compiled pattern is stored.) As you can see I'm effectively assuming that every time re.compile() is called with the same input pattern it will return the exact same object rather than a second, identical, object. In interactive tests via python shell this seems to be the case but... can I rely on it - always- being the case? Or is it one of those implementation-specific issues? As MRAB indicated, this only works because the CPython re module itself has a cache so you do not have to make one. It is, however, limited to 100 or so since programs that use patterns repeatedly generally use a limited number of patterns. Caches usually use a dict so that cache[input] == output and lookup is O(1). And what about any other function or class/method? Is there a way to discriminate between methods and functions that when invoked twice with the same arguments will return the same object and those that in the same circumstances will return two identical objects? In general, a function that calculates and return an object will return a new object. The exceptions are exceptions. If the answer is no, am I right to state the in the case portrayed above the only way to be safe is to use the following code instead? for item in compiledPatterns: if(item.pattern == pattern): Yes. Unless you are comparing against None (or True or False in Py3) or specifically know otherwise, you probably want '==' rather than 'is'. Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: DictReader and fieldnames
Ted Is it possible to grab the fieldnames that the csv DictReader
Ted module automatically reads from the first line of the input file?
Like this, perhaps?
rdr = csv.DictReader(open(f.csv, rb))
rdr.fieldnames
['col1', 'col2', 'color']
rdr.next()
{'color': '3', 'col2': '2', 'col1': '1'}
--
Skip Montanaro - s...@pobox.com - http://www.smontanaro.net/
--
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Re: Simple question about yyyy/mm/dd
Hi all, I need to receive in input a date represented by a string in the form /mm/dd (or reversed), then I need to assure that the date is = the current date and then split the dates in variables like year, month, day. Is there some module to do this quickly? The dateutil package has a parser module which works well here: import dateutil.parser, datetime dateutil.parser.parse(2008/03/31) datetime.datetime(2008, 3, 31, 0, 0) dateutil.parser.parse(2008/03/31) datetime.datetime.now() False -- Skip Montanaro - s...@pobox.com - http://www.smontanaro.net/ -- http://mail.python.org/mailman/listinfo/python-list
Threads not Improving Performance in Program
I have a parser that needs to process 7 million files. After running for 2 days, it had only processed 1.5 million. I want this script to parse several files at once by using multiple threads: one for each file currently being analyzed. My code iterates through all of the directories within a directory, and at each directory, iterates through each file in that directory. I structured my code something like this. I think I might be misunderstanding how to use threads: mythreads = [] for directory in dirList: #some processing... for file in fileList: p = Process(currDir,directory,file)#class that extends thread.Threading mythreads.append(p) p.start() for thread in mythreads: thread.join() del thread The actual class that extends threading.thread is below: class Process(threading.Thread): vlock = threading.Lock() def __init__(self,currDir,directory,file): #thread constructor threading.Thread.__init__(self) self.currDir = currDir self.directory = directory self.file = file def run(self): redirect = re.compile(r'#REDIRECT',re.I) xmldoc = minidom.parse(os.path.join(self.currDir,self.file)) try: markup = xmldoc.firstChild.childNodes[-2].childNodes[-2].childNodes[-2].childNodes[0].data except: #An error occurred Process.vlock.acquire() BAD = open(bad.log,a) BAD.writelines(self.file + \n) BAD.close() Process.vlock.release() print Error. return #if successful, do more processing... I did an experiment with a variety of numbers of threads and there is no performance gain. The code is taking the same amount of time to process 1000 files as it would if the code did not use threads. Any ideas on what I am doing wrong? -- http://mail.python.org/mailman/listinfo/python-list
Re: converting pipe delimited file to fixed width
digz wrote: Hi, I am trying to convert a | delimited file to fixed width by right padding with spaces, Here is how I have written the program , just get the feeling this can be done in a much better ( python functional ) way rather than the procedural code i have below . Any help appreciated #!/usr/bin/python def rightFill(fillString, toLength, fillChar): return fillString+''.join([fillChar for x in range(len (fillString),toLength)]) Ugh. That should be the same as return fillString + (toLength-length(fillString))*fillChar -- http://mail.python.org/mailman/listinfo/python-list
Re: converting pipe delimited file to fixed width
On Mar 19, 8:51 am, digz digvijo...@gmail.com wrote:
Hi,
I am trying to convert a | delimited file to fixed width by right
padding with spaces, Here is how I have written the program , just get
the feeling this can be done in a much better ( python functional )
way rather than the procedural code i have below . Any help
appreciated
#!/usr/bin/python
def rightFill(fillString, toLength, fillChar):
return fillString+''.join([fillChar for x in range(len
(fillString),toLength)])
fieldWidth=[ 14, 6, 18, 21, 21,4, 6 ];
file = open(/home/chatdi/input.csv, r);
lines = file.readlines()
file.close()
out = open( /home/chatdi/ouptut.csv, 'w')
for line in lines:
line = line[:-1]
index = 0
for token in line.split('|'):
paddedToken = rightFill(token, fieldWidth[index], ' ' )
out.write( paddedToken )
index = index + 1
out.write(\n)
Caveat: none of the solutions (including mine) deal with the case of
the field being longer than the width. You might want to throw an
exception.
I use the csv module to do the reading of the file, i am going to do
some testing to see if i can set the delimiter to '' so that i can
also use it for the output. For now this should work.
http://docs.python.org/library/csv.html
import csv
fieldWidth=[ 14, 6, 18, 21, 21,4, 6 ];
csvfilepath = 'somefile.csv'
outcsvfilepath = 'someoutfile.csv'
endl = '\n'
f = open(csvfilepath)
outf = open(outcsvfilepath)
csvfile = csv.reader(f,delimiter = '|')
for row in csvfile:
outrow = [ field + fillchar * (width - len(field)) for width, field
in zip(fieldWidth,row)]
outcsv.write( ''.join(outrow))
outcsv.write( endl )
f.close()
outf.close()
--
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cross compile Python to Linux-ARM
Hi, We are looking to use Python on an embedded Linux ARM system. What I gather from googling the subject is that it is not that straight forward (a fair amount of patching hacking). Nobody out there that has done it claims it is easy, which makes me worried. I haven't seen a description on porting Python 2.6 or 3.0 yet. Is it much different than for the earlier versions (the latest I have seem is Python 2.5). Does it matter whether Python is cross compiled to Linux 2.4 or Linux 2.6 ? Can anyone point to a howto they know works well ? What are the chances of an 'officially' supported ARM-Linux Python distribution ? (or is it safer to wait for industrial spec Intel Atom boards to avoid the cross compilation altogether ? What would it take for the Linux version of Python to be easily cross compiled (i.e. would the Linux-Python maintainers be willing to include and maintain cross-compilation specific functions) ? Let's say we can get it done. How is the performance and stability of a working Python on an embedded ARM-Linux system ? Does cross compiling Python automatically include the standard Python library, or is that yet another adventure ? thanks -- http://mail.python.org/mailman/listinfo/python-list
Missing values in tuple assignment
Use case: parsing a simple config file line where lines start with a
keyword and have optional arguments. I want to extract the keyword and
then pass the rest of the line to a function to process it. An obvious
use of split(None,1)
cmd,args= = line.split(None,1);
if cmd in self.switch: self.switch[cmd](self,args)
else: self.errors.append(unrecognized keyword '{0)'.format(cmd))
Here's a test in IDLE:
a=now is the time
x,y=a.split(None,1)
x
'now'
y
'is the time'
However, if the optional argument string is missing:
a=now
x,y=a.split(None,1)
Traceback (most recent call last):
File pyshell#42, line 1, in module
x,y=a.split(None,1)
ValueError: need more than 1 value to unpack
I understand the problem is not with split() but with the assignment
to a tuple. Is there a way to get the assignment to default the
missing values to None?
--
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Re: Threads not Improving Performance in Program
On Mar 19, 9:50 am, Ryan Rosario uclamath...@gmail.com wrote: I have a parser that needs to process 7 million files. After running for 2 days, it had only processed 1.5 million. I want this script to parse several files at once by using multiple threads: one for each file currently being analyzed. My code iterates through all of the directories within a directory, and at each directory, iterates through each file in that directory. I structured my code something like this. I think I might be misunderstanding how to use threads: mythreads = [] for directory in dirList: #some processing... for file in fileList: p = Process(currDir,directory,file) #class that extends thread.Threading mythreads.append(p) p.start() for thread in mythreads: thread.join() del thread The actual class that extends threading.thread is below: class Process(threading.Thread): vlock = threading.Lock() def __init__(self,currDir,directory,file): #thread constructor threading.Thread.__init__(self) self.currDir = currDir self.directory = directory self.file = file def run(self): redirect = re.compile(r'#REDIRECT',re.I) xmldoc = minidom.parse(os.path.join(self.currDir,self.file)) try: markup = xmldoc.firstChild.childNodes[-2].childNodes[-2].childNodes[-2].childNodes[0].data except: #An error occurred Process.vlock.acquire() BAD = open(bad.log,a) BAD.writelines(self.file + \n) BAD.close() Process.vlock.release() print Error. return #if successful, do more processing... I did an experiment with a variety of numbers of threads and there is no performance gain. The code is taking the same amount of time to process 1000 files as it would if the code did not use threads. Any ideas on what I am doing wrong? Perhabs the bottleneck is the IO. How big are the files you are trying to parse? Another possible bottleneck is that threads share memory. Thread construction is also expensive in python, try looking up a threadPool class. (ThreadPools are collections of threads that do work, when they finish they go to an idle state untill you give them more work, that way you aren't constantly creating new threads which is expensive) -- http://mail.python.org/mailman/listinfo/python-list
Re: Simple question about yyyy/mm/dd
mattia wrote: Hi all, I need to receive in input a date represented by a string in the form /mm/dd (or reversed), then I need to assure that the date is = the current date and then split the dates in variables like year, month, day. Is there some module to do this quickly? Look into time.strptime --Scott David Daniels scott.dani...@acm.org -- http://mail.python.org/mailman/listinfo/python-list
Re: What happened to NASA at Python? :(
r wrote: On Mar 12, 3:31 am, Michele Simionato michele.simion...@gmail.com wrote: That's pretty much impossible. I am sure NASA uses all programming languages in existence, plus probably many internal ones we never heard of. True but... all([NASA.does_endorse(lang) for lang in NASA['languages']]) False As the code suggests NASA doesn't sport an endorsement of X languages on every X language's webpage, which i feel is very important for Python's image, along with Google(Even more important!!), ILM, and others. I am really not worried if NASA *actually* uses Python or not(or to what extent), just as long as they say they do is good enough for me. *wink-wink* There are about 40 people supporting the Mars Lander mission using Python and aiming for a launch window this September. Wish them luck! That's just one of the NASA groups relying heavily on Python. regards Steve -- Steve Holden +1 571 484 6266 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ Want to know? Come to PyCon - soon! http://us.pycon.org/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Missing values in tuple assignment
On Thu, 2009-03-19 at 11:57 -0500, Jim Garrison wrote:
Use case: parsing a simple config file line where lines start with a
keyword and have optional arguments. I want to extract the keyword and
then pass the rest of the line to a function to process it. An obvious
use of split(None,1)
cmd,args= = line.split(None,1);
if cmd in self.switch: self.switch[cmd](self,args)
else: self.errors.append(unrecognized keyword '{0)'.format(cmd))
Here's a test in IDLE:
a=now is the time
x,y=a.split(None,1)
x
'now'
y
'is the time'
However, if the optional argument string is missing:
a=now
x,y=a.split(None,1)
Traceback (most recent call last):
File pyshell#42, line 1, in module
x,y=a.split(None,1)
ValueError: need more than 1 value to unpack
I understand the problem is not with split() but with the assignment
to a tuple. Is there a way to get the assignment to default the
missing values to None?
why not do this?
a= 'now'
z = a.split(None, 1)
x = z[0]
y = z[1] if len(z) == 2 else None
--
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Re: Strange crash issue on Windows w/ PyGTK, Cairo...
CJ Kucera wrote: Anyway, the issue turned out to be zlib.decompress() - for larger sets of data, if I wasn't specifying bufsize, the malloc()s that it was doing behind-the-scenes must have been clobbering memory. As soon as I specified bufsize, everything was totally kosher. Okay, I've got a reproducible testcase of this available up here: http://apocalyptech.com/pygtk-zlib/ I'm no longer *totally* convinced that it's a zlib issue... zlib's call actually returns a valid string, and the error happens later in the app. I've yet to be able to engineer a crash using anything other than that cairo.ImageSurface.create_from_png() function, so it's possible that specifying bufsize in zlib.decompress() merely allocates memory in such a way that a bug in PyCairo doesn't come to light in that case. So, I'm not really sure if I should submit this to Python or PyGTK's tracker yet. Could someone check it out and let me know what you think? That'd be great. Thanks! As I mention on that page, removing import os and import sys will fix the issue on XP, though you can remove them on win2k and still see the crash. Thanks, CJ -- WOW: Flemmy| The ships hung in the sky in much the same p...@apocalyptech.com |way that bricks don't. - Douglas Adams, 24.24.2.3171 | _The Hitchhiker's Guide To The Galaxy_ -- http://mail.python.org/mailman/listinfo/python-list
Re: Memory efficient tuple storage
In the end, I used a cStringIO object to store the chromosomes - because there are only 23, I can use one character for each chromosome and represent the whole lot with a giant string and a dictionary to say what each character means. Then I used numpy arrays for the data and coordinates. This squeezed each file into under 100MB. Thanks again for the help! Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: What happened to NASA at Python? :(
s...@pobox.com wrote: In fact, graphics were added for several organizations. I believe they will be chosen randomly. NASA is still there. MiO In that case, they must be using the random number generator from MiO Dilbert. You know, the one that said 9, 9, 9, 9,... Sorry, randomly chosen whenever the front page is rebuilt by one of the web gnomes. It's not chosen randomly on each page fetch. Though of course it easily *could* be, and I hope it soon *will* be. More about that in my PyCon talk ... regards Steve -- Steve Holden +1 571 484 6266 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ Want to know? Come to PyCon - soon! http://us.pycon.org/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Can I rely on...
Thank you everybody for the informative replies. I'll have to comb my code for all the instances of item in sequence statement because I suspect some of them are as unsafe as my first example. Oh well. One more lesson learned. Thank you again. Manu -- http://mail.python.org/mailman/listinfo/python-list
Re: What happened to NASA at Python? :(
There are about 40 people supporting the Mars Lander mission using Python and aiming for a launch window this September. Wish them luck! What, exactly, are they using Python for? -- Dotan Cohen http://what-is-what.com http://gibberish.co.il א-ב-ג-ד-ה-ו-ז-ח-ט-י-ך-כ-ל-ם-מ-ן-נ-ס-ע-ף-פ-ץ-צ-ק-ר-ש-ת ا-ب-ت-ث-ج-ح-خ-د-ذ-ر-ز-س-ش-ص-ض-ط-ظ-ع-غ-ف-ق-ك-ل-م-ن-ه-و-ي А-Б-В-Г-Д-Е-Ё-Ж-З-И-Й-К-Л-М-Н-О-П-Р-С-Т-У-Ф-Х-Ц-Ч-Ш-Щ-Ъ-Ы-Ь-Э-Ю-Я а-б-в-г-д-е-ё-ж-з-и-й-к-л-м-н-о-п-р-с-т-у-ф-х-ц-ч-ш-щ-ъ-ы-ь-э-ю-я ä-ö-ü-ß-Ä-Ö-Ü -- http://mail.python.org/mailman/listinfo/python-list
Re: How complex is complex?
On Mar 19, 9:41 am, Kottiyath n.kottiy...@gmail.com wrote: On Mar 19, 9:33 pm, Kottiyath n.kottiy...@gmail.com wrote: On Mar 19, 8:42 pm, Paul McGuire pt...@austin.rr.com wrote: On Mar 19, 4:39 am, Kottiyath n.kottiy...@gmail.com wrote: I understand that my question was foolish, even for a newbie. I will not ask any more such questions in the future. Gaaah! Your question was just fine, a good question on coding style. I wish more people would ask such questions so that bad habits could be avoided. The newbie posts that are annoying are the ones that: - are answered on page 1 of any tutorial (how do I get the second character of a string?) - are obvious homework assignments with no actual effort on the poster's part (how do I write a Python program to find the first 10 prime numbers?) - pontificate on what is wrong with Python, based on 2 hours' experience with the language (often titled What's wrong with Python, with content like Python sucks because it doesn't have a switch statement/has significant whitespace/doesn't check types of arguments/ isn't totally object-oriented like Java/doesn't have interfaces/...) - are so vague as to be just Usenet noise (titled Help me, with no content, or i need to write a program and don't know where to start can someone write it for me?) I think Daniel's joke was on the rest of us, who each had to chime in with our favorite dict processing algorithm. It *would* be good for you as a newbie to get an appreciation of the topics that were covered in these responses, though, especially the distinction between updating the dict in-place vs. creating a new dict. -- Paul Daniel, Sorry for misunderstanding your post. I hope I was not being passive-aggresive - (also because I found that the second mechanism I provided was quite horrible :-), so I was indeed being foolish there. ) Paul/Aahz, I did understand 2 things (1) When using map always consider that the function will be called everytime, so the hit on the performance is more. (2) The second mechanism and the first mechanism provides different solutions (new dict/same dict) both of which I did not think about at all. Also, thank you everyone for all the help. I have been following this thread for the last 4 months (when I started with python) and I have learned a lot. The amount of help provided here is amazing. p.s. - English is indeed not my first language :-) Oops, Forgot to mention the biggest learning. Readability is better than brevity - I rewrote your sentence to be more optimized. Readability brevity ;-) Thanks to Rhodri. This was a question which was bugging me all the time. When I look at code, I am always envious when I see the same code written in much smaller number of lines. Now, I will force myself to ask the questions Rhodri proposed (esp: does it look uglier part) before deciding whether or not to go ahead with brevity. -- http://mail.python.org/mailman/listinfo/python-list
Re: What happened to NASA at Python? :(
[posted and e-mailed] In article mailman.2216.1237483574.11746.python-l...@python.org, Dotan Cohen dotanco...@gmail.com wrote: PiBUaGVyZSBhcmUgYWJvdXQgNDAgcGVvcGxlIHN1cHBvcnRpbmcgdGhlIE1hcnMgTGFuZGVyIG1p c3Npb24gdXNpbmcKPiBQeXRob24gYW5kIGFpbWluZyBmb3IgYSBsYXVuY2ggd2luZG93IHRoaXMg U2VwdGVtYmVyLiBXaXNoIHRoZW0gbHVjayEKPgoKV2hhdCwgZXhhY3RseSwgYXJlIHRoZXkgdXNp bmcgUHl0aG9uIGZvcj8KCi0tIApEb3RhbiBDb2hlbgoKaHR0cDovL3doYXQtaXMtd2hhdC5jb20K aHR0cDovL2dpYmJlcmlzaC5jby5pbAoK15At15Et15It15Mt15Qt15Ut15Yt15ct15gt15kt15ot 15st15wt150t154t158t16At16Et16It16Mt16Qt16Ut16Yt16ct16gt16kt16oK2Kct2Kgt2Kot 2Kst2Kwt2K0t2K4t2K8t2LAt2LEt2LIt2LMt2LQt2LUt2LYt2Lct2Lgt2Lkt2Lot2YEt2YIt2YMt 2YQt2YUt2YYt2YfigI0t2Ygt2YoK0JAt0JEt0JIt0JMt0JQt0JUt0IEt0JYt0Jct0Jgt0Jkt0Jot 0Jst0Jwt0J0t0J4t0J8t0KAt0KEt0KIt0KMt0KQt0KUt0KYt0Kct0Kgt0Kkt0Kot0Kst0Kwt0K0t 0K4t0K8K0LAt0LEt0LIt0LMt0LQt0LUt0ZEt0LYt0Lct0Lgt0Lkt0Lot0Lst0Lwt0L0t0L4t0L8t 0YAt0YEt0YIt0YMt0YQt0YUt0YYt0Yct0Ygt0Ykt0Yot0Yst0Ywt0Y0t0Y4t0Y8Kw6Qtw7Ytw7wt w58tw4Qtw5Ytw5wK Could you perhaps be persuaded to post in ASCII? -- Aahz (a...@pythoncraft.com) * http://www.pythoncraft.com/ Programming language design is not a rational science. Most reasoning about it is at best rationalization of gut feelings, and at worst plain wrong. --GvR, python-ideas, 2009-3-1 -- http://mail.python.org/mailman/listinfo/python-list
