PyPy Gothenburg Post-Easter Sprint April 25 - May 1 2011
PyPy Göteborg Post-Easter Sprint April 25 - May 1 2011 == The next PyPy sprint will be in Gothenburg, Sweden. It is a public sprint, very suitable for newcomers. We'll focus on making the 1.5 release (if it hasn't already happened) and whatever interests the Sprint attendees. Topics and goals The main goal is to polish and release PyPy 1.5, supporting Python 2.7 as well as the last few months' improvements in the JIT (provided that it hasn't already happened). Other topics: - Going over our documentation, and classifying our docs in terms of mouldiness. Deciding what needs writing, and maybe writing it. - Helping people get their code running with PyPy - maybe work on EuroPython Training, and talks - Summer of Code preparation - speed.pypy.org - any other programming task is welcome too -- e.g. tweaking the Python or JavaScript interpreter, Stackless support, and so on. Location The sprint will be held in the apartment of Laura Creighton and Jacob Hallén which is at Götabergsgatan 22 in Gothenburg, Sweden. Here is a map_. This is in central Gothenburg. It is between the tram_ stops of Vasaplatsen and Valand, (a distance of 4 blocks) where many lines call -- the 2, 3, 4, 5, 7, 10 and 13. .. _tram: http://www.vasttrafik.se/en/ .. _map: http://bit.ly/grRuQe Probably cheapest and not too far away is to book accomodation at `SGS Veckobostader`_. The `Elite Park Avenyn Hotel`_ is a luxury hotel just a few blocks away. There are scores of hotels a short walk away from the sprint location, suitable for every budget, desire for luxury, and desire for the unusual. You could, for instance, stay on a `boat`_. Options are too numerous to go into here. Just ask in the mailing list or on the blog. .. _`SGS Veckobostader`: http://www.sgsveckobostader.se/en .. _`Elite Park Avenyn Hotel`: http://www.elite.se/hotell/goteborg/park/ .. _`boat`: http://www.liseberg.se/en/home/Accommodation/Hotel/Hotel-Barken-Viki ng/ Hours will be from 10:00 until people have had enough. It's a good idea to arrive a day before the sprint starts and leave a day later. In the middle of the sprint there usually is a break day and it's usually ok to take half-days off if you feel like it. Good to Know Sweden is not part of the Euro zone. One SEK (krona in singular, kronor in plural) is roughly 1/10th of a Euro (9.36 SEK to 1 Euro). The venue is central in Gothenburg. There is a large selection of places to get food nearby, from edible-and-cheap to outstanding. We often cook meals together, so let us know if you have any food allergies, dislikes, or special requirements. Sweden uses the same kind of plugs as Germany. 230V AC. The Sprint will be held the week following Easter. This means, as always, that Gothcon_ will be taking place the weekend before (Easter weekend). Gothcon, now in its 35 year, is the largest European game players conference. Some of you may be interested in arriving early for the board games. The conference site is only in Swedish, alas. You don't need to register in advance unless you are planning to host a tournament, (and it's too late for that anyway). .. _Gothcon: http://www.gothcon.se/ Getting Here If are coming train, you will arrive at the `Central Station`_. It is about 12 blocks to the site from there, or you can take a tram_. There are two airports which are local to Göteborg, `Landvetter`_ (the main one) and `Gothenburg City Airport`_ (where some budget airlines fly). If you arrive at `Landvetter`_ the airport bus stops right downtown at `Elite Park Avenyn Hotel`_ which is the second stop, 4 blocks from the Sprint site, as well as the end of the line, which is the `Central Station`_. If you arrive at `Gothenburg City Airport`_ take the bus to the end of the line. You will be at the `Central Station`_. You can also arrive by ferry_, from either Kiel in Germany or Frederikshavn in Denmark. .. _`Central Station`: http://bit.ly/fON43p .. _`Landvetter`: http://swedavia.se/en/Goteborg/Traveller-information/Traffic-i nformation/ .. _`Gothenburg City Airport`: http://www.goteborgairport.se/eng.asp .. _ferry: http://www.stenaline.nl/en/ferry/ Who's Coming? -- If you'd like to come, please let us know when you will be arriving and leaving, as well as letting us know your interests We'll keep a list of `people`_ which we'll update (which you can do so yourself if you have bitbucket pypy commit rights). .. _`people`: https://bitbucket.org/pypy/extradoc/src/tip/sprintinfo/gothenburg- 2011/people.txt -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations/
Toronto PyCamp 2011
The University of Toronto Department of Physics brings PyCamp to Toronto on Monday, June 27 through Thursday, June 30, 2011. Register today at http://trizpug.org/boot-camp/torpy11/ For beginners, this ultra-low-cost Python Boot Camp makes you productive so you can get your work done quickly. PyCamp emphasizes the features which make Python a simpler and more efficient language. Following along with example Python PushUps™ speeds your learning process. Become a self-sufficient Python developer in just four days at PyCamp! Pycamp is conducted on the campus of the University of Toronto in a state of the art high technology classroom. -- Sincerely, Chris Calloway http://nccoos.org/Members/cbc office: 3313 Venable Hall phone: (919) 599-3530 mail: Campus Box #3300, UNC-CH, Chapel Hill, NC 27599 -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations/
Thinking and Analysis based on Marxism Literature
For getting good knowledge about Marxism and Literature, Marx his Opinions to sharpen thinking analytically, don't forget to click on the website given below:- www.analyzethink.blogspot.com -- http://mail.python.org/mailman/listinfo/python-list
News
For getting the effective information on the News, please click on this website: www.ml97712.blogspot.com This website will provide you the knowledge about the best news. -- http://mail.python.org/mailman/listinfo/python-list
Jobs
If you want to get the innovative information on the Job job Market, please click on this website: www.111jobs.blogspot.com This website is based on the job technique and idea. -- http://mail.python.org/mailman/listinfo/python-list
Re: running Python2 Python3 parallel concurrent
On Mar 31, 6:05 am, harrismh777 harrismh...@charter.net wrote: Greetings, The purpose of this communique is to document a process for installing python2.7.1 in parallel with python3.2 on a concurrent desktop with independent idle and python path structure. Not sure if this is relevant... python-mode (emacs mode for python development) is broken for python 3 I submitted a 1-line patch which makes python-mode work for 2.x and 3.x Here https://bugs.launchpad.net/python-mode/+bug/450552 -- http://mail.python.org/mailman/listinfo/python-list
Re: Testing for performance regressions
On Mon, Apr 4, 2011 at 10:25 PM, Steven D'Aprano steve+comp.lang.pyt...@pearwood.info wrote: On Mon, 04 Apr 2011 20:59:52 -0700, geremy condra wrote: On Mon, Apr 4, 2011 at 7:45 PM, Steven D'Aprano steve+comp.lang.pyt...@pearwood.info wrote: * The disclaimers about timing code snippets that can be found in the timeit module apply. If possible, use timeit rather than roll-you-own timers. Huh. In looking into timing attacks actually one of the biggest lessons I learned was *not* to use timeit- that the overhead and variance involved in using it will wind up consuming small changes in behavior in ways that are fairly opaque until you really take it apart. Do you have more details? I follow the advice in the timeit module, and only ever look at the minimum value, and never try to calculate a mean or variance. Given the number of outside influences (What do you mean starting up a browser with 200 tabs at the same time will affect the timing?), I wouldn't trust a mean or variance to be meaningful. I think it's safe to treat timeit as an opaque, medium-precision benchmark with those caveats. If you need actual timing data though- answering the question 'how much faster?' rather than 'which is faster?' just taking actual timings seems to provide much, much better answers. Part of that is because timeit adds the cost of the for loop to every run- here's the actual code: def inner(_it, _timer): %(setup)s _t0 = _timer() for _i in _it: %(stmt)s _t1 = _timer() return _t1 - _t0 (taken from Lib/timeit.py line 81) where %(setup)s and %(stmt)s are what you passed in. Obviously, if the magnitude of the change you're looking for is smaller than the variance in the for loop's overhead this makes things a lot harder than they need to be, and the whole proposition gets pretty dodgy for measuring in the sub-millisecond range, which is where many timing attacks are going to lay. It also has some problems at the opposite end of the spectrum- timing large, long-running, or memory-intensive chunks of code can be deceptive because timeit runs with the GC disabled. This bit me a while back working on Graphine, actually, and it confused the hell out of me at the time. I'm also not so sure about the 'take the minimum' advice. There's a reasonable amount of empirical evidence suggesting that timings taken at the 30-40% mark are less noisy than those taken at either end of the spectrum, especially if there's a network performance component. YMMV, of course. Geremy Condra -- http://mail.python.org/mailman/listinfo/python-list
replace regex in file using a dictionary
Hi,
So i want to replace multiple lines in a text file and I have reasoned
the best way to do this is with a dictionary. I have simplified my
example and broadly I get what I want however I am now printing my
replacement string and part of the original expression. I am guessing
that I will need to use a more complicated expression than I am
currently am to achieve what I want?
my aim is to match the expression before the = and replace the
string after the equals...
My failed example...
def replace_keys(text, replacements_dict):
for key, var in replacements_dict.iteritems():
replacement = %s = %s % (key, var)
text = text.replace(key, replacement)
return text
# example of two lines of the file
str = \
structcn = 150.0
metfrac0 = 0.85
# replacements
replacement_dict = {structcn: 999.0, metfrac0: 0.85}
new_str = replace_keys(str, replacement_dict)
print str
print
print new_str
which produces...
structcn = 150.0
metfrac0 = 0.85
structcn = 999.0 = 150.0
metfrac0 = 0.85 = 0.85
thanks.
--
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Re: XML header with lxml
Jabba Laci, 04.04.2011 18:54: I want to construct an XML file with lxml but I don't find how to add the '?xml version=1.0?' header. This is not required. According to the XML spec, the default is: ?xml version=1.0 encoding=utf-8 standalone=false? So, unless you diverge from these values, you do not need an XML declaration in your file. If you want to output the declaration anyway, you can simply prepend it to the string or write it into the output file before serialising. from lxml import etree as ET html = ET.Element(html) print ET.tostring(html) simply prints html/ I imagine you are aware that HTML isn't XML. Stefan -- http://mail.python.org/mailman/listinfo/python-list
Re: XML header with lxml
Chroma Key, 04.04.2011 21:49: On 2011-04-04 18:54:40 +0200, Jabba Laci said: I want to construct an XML file with lxml but I don't find how to add the '?xml version=1.0?' header. from lxml import etree as ET html = ET.Element(html) print ET.tostring(html) Add the xml_declaration=True as an argument of etree.tostring(). Ah, yes. That's the right way to do it (if you need it). Stefan -- http://mail.python.org/mailman/listinfo/python-list
Re: replace regex in file using a dictionary
2011/4/5 Martin De Kauwe mdeka...@gmail.com:
Hi,
So i want to replace multiple lines in a text file and I have reasoned
the best way to do this is with a dictionary. I have simplified my
example and broadly I get what I want however I am now printing my
replacement string and part of the original expression. I am guessing
that I will need to use a more complicated expression than I am
currently am to achieve what I want?
my aim is to match the expression before the = and replace the
string after the equals...
My failed example...
[...]
thanks.
--
Hi,
I guess, you would have to split the line and extract the substrings
before and after = and replace only the value part.
Or you can use regular expression replace with a replacement function,
e.g. like the following sample.
The re pattern would probably need some tweaking to match the variable
names, the values and the whitespace around =; and, of course, it
shouldn't match anything unwanted in the original text ...
hth,
vbr
import re
orig_str = structcn = 150.0
metfrac0 = 0.85
unknown7 = 38.2
replacement_dict = {structcn: 999.0, metfrac0: 0.85}
def repl_fn(m):
return m.group(1) + m.group(2) + replacement_dict.get(m.group(1),
m.group(3))
new_str = re.sub(r([\w\d_]+?)( = )([\d.-]+), repl_fn, orig_str)
print new_str
--
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3D subfigures in matplotlib?
How can I make maybe 3D subfigures with Python and matplotlib? I found the following example (http://matplotlib.sourceforge.net/ examples/mplot3d/subplot3d_demo.html), but it doesn't work. --- from mpl_toolkits.mplot3d.axes3d import Axes3D import matplotlib.pyplot as plt # imports specific to the plots in this example import numpy as np from matplotlib import cm from mpl_toolkits.mplot3d.axes3d import get_test_data fig = plt.figure(figsize=(9.5,5.0)) # First subplot ax = fig.add_subplot(1, 2, 1, projection='3d') X = np.arange(-5, 5, 0.25) Y = np.arange(-5, 5, 0.25) X, Y = np.meshgrid(X, Y) R = np.sqrt(X**2 + Y**2) Z = np.sin(R) surf = ax.plot_surface(X, Y, Z, rstride=1, cstride=1, cmap=cm.jet, linewidth=0, antialiased=False) ax.set_zlim3d(-1.01, 1.01) fig.colorbar(surf, shrink=0.5, aspect=10) # Second subplot ax = fig.add_subplot(1, 2, 2, projection='3d') X, Y, Z = get_test_data(0.05) ax.plot_wireframe(X, Y, Z, rstride=10, cstride=10) plt.show() The error message is: ax = fig.add_subplot(1, 2, 1, projection='3d') Traceback (most recent call last): File stdin, line 1, in module File /usr/lib/pymodules/python2.6/matplotlib/figure.py, line 677, in add_subplot projection_class = get_projection_class(projection) File /usr/lib/pymodules/python2.6/matplotlib/projections/ __init__.py, line 61, in get_projection_class raise ValueError(Unknown projection '%s' % projection) ValueError: Unknown projection '3d' I am using Python 2.6.6., and matplotlib 0.99.3. How can I make several subfigures in 3D? -- http://mail.python.org/mailman/listinfo/python-list
Re: replace regex in file using a dictionary
How about creating a new string instead of replacing the original.
def replace_keys(text, replacements_dict):
text_list = text.split('\n')
new_text = ''
for line in text_list:
key=line.split('=')[0]
if key.strip() in replacements_dict:
new_text = new_text + key + '=' + replacements_dict[key.strip()]
+ \n
else:
new_text = new_text + line
return new_text
On 5 April 2011 09:32, Vlastimil Brom vlastimil.b...@gmail.com wrote:
2011/4/5 Martin De Kauwe mdeka...@gmail.com:
Hi,
So i want to replace multiple lines in a text file and I have reasoned
the best way to do this is with a dictionary. I have simplified my
example and broadly I get what I want however I am now printing my
replacement string and part of the original expression. I am guessing
that I will need to use a more complicated expression than I am
currently am to achieve what I want?
my aim is to match the expression before the = and replace the
string after the equals...
My failed example...
[...]
thanks.
--
Hi,
I guess, you would have to split the line and extract the substrings
before and after = and replace only the value part.
Or you can use regular expression replace with a replacement function,
e.g. like the following sample.
The re pattern would probably need some tweaking to match the variable
names, the values and the whitespace around =; and, of course, it
shouldn't match anything unwanted in the original text ...
hth,
vbr
import re
orig_str = structcn = 150.0
metfrac0 = 0.85
unknown7 = 38.2
replacement_dict = {structcn: 999.0, metfrac0: 0.85}
def repl_fn(m):
return m.group(1) + m.group(2) + replacement_dict.get(m.group(1),
m.group(3))
new_str = re.sub(r([\w\d_]+?)( = )([\d.-]+), repl_fn, orig_str)
print new_str
--
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--
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Python benefits over Cobra
I just came across the Cobra language, which appears to be heavily influenced by Python (and other languages). The pitch sounds great. It's supposed to have: 1. Quick, expressive coding 2. Fast execution 3. Static and dynamic binding 4. Language level support for quality http://cobra-language.com/docs/why/ http://cobra-language.com/docs/python/ I was wondering what advantages Python has over Cobra. I know it's probably a difficult question to answer and depends on specific requirements. All I can think of is: * Maturity of language o Robust and tested. o availability of modules (standard and built-in). o large community support (commercial and non-commercial). * No dependence of .NET/Mono o I don't know if this is an pro or con as I don't know .NET. Presumably the maturity argument would be less significant over time. I'm not sure about the .NET/Mono framework, whether that is good or bad. Sounds good in some situations at least. Any other arguments where Python has benefits over Cobra ?? Cheers, Brendan. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python benefits over Cobra
On 05-Apr-11 06:22 AM, Brendan Simon (eTRIX) wrote: I just came across the Cobra language, which appears to be heavily influenced by Python (and other languages). The pitch sounds great. It's supposed to have: 1. Quick, expressive coding 2. Fast execution 3. Static and dynamic binding 4. Language level support for quality http://cobra-language.com/docs/why/ http://cobra-language.com/docs/python/ I was wondering what advantages Python has over Cobra. I know it's probably a difficult question to answer and depends on specific requirements. All I can think of is: * Maturity of language o Robust and tested. o availability of modules (standard and built-in). o large community support (commercial and non-commercial). * No dependence of .NET/Mono o I don't know if this is an pro or con as I don't know .NET. Presumably the maturity argument would be less significant over time. I'm not sure about the .NET/Mono framework, whether that is good or bad. Sounds good in some situations at least. Any other arguments where Python has benefits over Cobra ?? Cheers, Brendan. Two questions: 1. Is Cobra Open Source? 2. The blog ended on October, did he run out of steam? I liked the '.', in place of '.self', but that's been rejected for Python. Colin W. -- http://mail.python.org/mailman/listinfo/python-list
is python 3 better than python 2?
what are the advantages? if it wasn't for python 3 breaking backwards compatibility would it be the better choice? -- http://mail.python.org/mailman/listinfo/python-list
python fighting game?(like street fighter)
are there any good fighting games in the style of street fighter or guilty gear? -- http://mail.python.org/mailman/listinfo/python-list
Re: Python benefits over Cobra
Cobra seems interessant, open-source, but the dependance on Mono and .Net annoy me a bit. Otherwise, cobra have good ideas, a syntax similar to python. One thing i really love is the How-To and the Samples pages on it's website, i think it's a very good thing for beginners. FELD Boris 2011/4/5 Colin J. Williams c...@ncf.ca: On 05-Apr-11 06:22 AM, Brendan Simon (eTRIX) wrote: I just came across the Cobra language, which appears to be heavily influenced by Python (and other languages). The pitch sounds great. It's supposed to have: 1. Quick, expressive coding 2. Fast execution 3. Static and dynamic binding 4. Language level support for quality http://cobra-language.com/docs/why/ http://cobra-language.com/docs/python/ I was wondering what advantages Python has over Cobra. I know it's probably a difficult question to answer and depends on specific requirements. All I can think of is: * Maturity of language o Robust and tested. o availability of modules (standard and built-in). o large community support (commercial and non-commercial). * No dependence of .NET/Mono o I don't know if this is an pro or con as I don't know .NET. Presumably the maturity argument would be less significant over time. I'm not sure about the .NET/Mono framework, whether that is good or bad. Sounds good in some situations at least. Any other arguments where Python has benefits over Cobra ?? Cheers, Brendan. Two questions: 1. Is Cobra Open Source? 2. The blog ended on October, did he run out of steam? I liked the '.', in place of '.self', but that's been rejected for Python. Colin W. -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Suggest some exercises on Python
Hi all, I'm a new bie. I have just started learning Python (3.0), finished with official tutorial. I would like to have your opinion on some 1. Good books (for an intermediate in programming) with lot's of exercise i can try it out. For example when i started with Perl i was going through a book 'Learning Perl' and it contained lots of exercises which made me confident. 2. Or any link or site which suggests some exercises to do in Python. When i was looking for some similar threads in some sites, they propose some sites which gives some exercises and puzzles to solve in python. But i'm feeling it's too much complicated for my capability. Cheers Jins thomas -- http://mail.python.org/mailman/listinfo/python-list
Re: Fun python 3.2 one-liner
what is the character limit on a one liner :P. For PEP 8 compliance, 80 characters. :-) Yeah, but we don't live in the 80's or 90's anymore and our screens can support xterms (or let alone IDE widows) much wider than 80 characters. I'm using 140 for python these days. Seriously, who would want to limit him/herself to 80 characters in 2011? Cheers, Daniel -- Psss, psss, put it down! - http://www.cafepress.com/putitdown -- http://mail.python.org/mailman/listinfo/python-list
Re: proposal to allow to set the delimiter in str.format to something other than curly bracket
On 2011-04-04, Alia Khouri alia_kho...@yahoo.com wrote: Nice! I didn't think of that. I guess I could get some additional performance by taking the re.compile step out of the function. Thanks for the tip! I recommend The Pragmatic Programmer, (Hunt, Thomas) ISBN 978-0201616224 and The Practice of Programming, (Kernighan, Pike) ISBN 978-0201615869 for more practical tips like this one. As a mostly self-taught programmer, both books helped me immensely. If you're a seasoned pro with a CS degree, you might not find them quite as interesting, though. The second book, especially, does not cover issues relating to large scale software development. As for factoring out re.compile, I believe they are cached by the re module, so you would save the cost of retrieving the cached regex, but not the cost of building it. -- Neil Cerutti -- http://mail.python.org/mailman/listinfo/python-list
Re: running Python2 Python3 parallel concurrent
rusi wrote: Not sure if this is relevant... python-mode (emacs mode for python development) is broken for python 3 I submitted a 1-line patch which makes python-mode work for 2.x and 3.x Its relevant to Mac OSX, but not so much for what I'm doing in Linux, here. On the other hand, I can't see (at the moment) why the technique I'm showing here would not work on the Mac. Although, I have not compiled sources on my Mac yet. That is for another day. In fact, I really think I'm about ready to scrap the Mac OSX and just run BLAG linux on it... I have a Mac Mini and I'm fed up with proprietary software (OS and other). Well, if you read PEP 394 you will get a really good idea of what is wrong with windows way down under its lame covers. But that is also another story for another day. kind regards, m harris -- http://mail.python.org/mailman/listinfo/python-list
Re: is python 3 better than python 2?
neil wrote: what are the advantages? if it wasn't for python 3 breaking backwards compatibility would it be the better choice? IMHO the killer app for Python 3 is in more reasonable support for foreign character sets (no matter where your are, at least one out of the hundred-odd Unicode character sets is going to be foreign,) and generally internationalized data processing. Mel. -- http://mail.python.org/mailman/listinfo/python-list
How to program in Python to run system commands in 1000s of servers
Here is my problem: Want to program in python to run sysadmin commands across 1000s of servers and gather the result in one place. Many times the commands need to be run as root. We cannot use ssh as root remote connectivity as well. What are the different ways of programming in python to achieve this? -- http://mail.python.org/mailman/listinfo/python-list
Re: Fun python 3.2 one-liner
On Tue, 05 Apr 2011 15:38:28 +0200, Daniel Fetchinson wrote: what is the character limit on a one liner :P. For PEP 8 compliance, 80 characters. :-) Yeah, but we don't live in the 80's or 90's anymore and our screens can support xterms (or let alone IDE widows) much wider than 80 characters. I'm using 140 for python these days. Seriously, who would want to limit him/herself to 80 characters in 2011? Seriously, or is that a rhetorical question? People who like to have two source files side-by-side on a standard sized monitor, or three on a wide-screen monitor. People who need to read or edit source code on a virtual terminal rather than in a GUI console app. People who print out source code to read later. People with poor vision who need to use a significantly larger sized characters, and therefore can't fit as many on a line. People who might want to email code snippets without having them inconveniently wrapped by the mail client. People who don't like reading really long, overly complex, lines, and prefer to keep lines short for readability. And most importantly... people who want to have their code accepted into the Python standard library. Personally, I find that the discipline of keeping to 80 characters is good for me. It reduces the temptation of writing obfuscated Python one- liners when two lines would be better. The *only* time it is a burden is when I write doc strings, and even then, only a small one. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: Suggest some exercises on Python
On Tue, 2011-04-05 at 18:43 +0530, Jins Thomas wrote: Hi all, I'm a new bie. I have just started learning Python (3.0), finished with official tutorial. I would like to have your opinion on some 1. Good books (for an intermediate in programming) with lot's of exercise i can try it out. For example when i started with Perl i was going through a book 'Learning Perl' and it contained lots of exercises which made me confident. 2. Or any link or site which suggests some exercises to do in Python. When i was looking for some similar threads in some sites, they propose some sites which gives some exercises and puzzles to solve in python. But i'm feeling it's too much complicated for my capability. Cheers Jins thomas i suggest you try http://www.pythonchallenge.com/ its pretty fun and very hard as it goes on. this book has you write a game with each chapter, http://inventwithpython.com/chapters/ the first 4 chapters you can probably skip. -- http://mail.python.org/mailman/listinfo/python-list
Re: Fun python 3.2 one-liner
On Wed, Apr 6, 2011 at 1:07 AM, Steven D'Aprano
steve+comp.lang.pyt...@pearwood.info wrote:
On Tue, 05 Apr 2011 15:38:28 +0200, Daniel Fetchinson wrote:
Seriously, who would want to limit
him/herself to 80 characters in 2011?
Seriously, or is that a rhetorical question?
People who like to have two source files side-by-side on a standard
sized monitor, or three on a wide-screen monitor.
And most importantly... people who want to have their code accepted into
the Python standard library.
Is that 80 including indentation, or excluding? And if including, does
that put a hard limit of 20 indentation levels for standard library
code?
Only partly tongue-in-cheek. I have code that quite legitimately has
gone to ten tabs in, and stayed there, and has on occasion gone as far
as 12-16. Generally I just scroll my display horizontally and ignore
the preceding tab levels. And sometimes I cheat a bit, in C or Pike,
and don't indent at some level; if it's a loop (or more likely a
switch) that surrounds the entire function, I might do:
void functionname(parameters) {while (cond)
{
//code at one indent, not two
}}
Can't do that in Python - for better or for worse.
Chris Angelico
--
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Re: Fun python 3.2 one-liner
On Tue, 2011-04-05 at 15:38 +0200, Daniel Fetchinson wrote: Yeah, but we don't live in the 80's or 90's anymore and our screens can support xterms (or let alone IDE widows) much wider than 80 characters. I'm using 140 for python these days. Seriously, who would want to limit him/herself to 80 characters in 2011? I'd rather have two files open with 80 columns in them than a single file with 160 columns and have to switch between files. Tim Wintle -- http://mail.python.org/mailman/listinfo/python-list
Re: replace regex in file using a dictionary
On Apr 5, 3:59 am, Martin De Kauwe mdeka...@gmail.com wrote:
Hi,
So i want to replace multiple lines in a text file and I have reasoned
the best way to do this is with a dictionary. I have simplified my
example and broadly I get what I want however I am now printing my
replacement string and part of the original expression. I am guessing
that I will need to use a more complicated expression than I am
currently am to achieve what I want?
my aim is to match the expression before the = and replace the
string after the equals...
My failed example...
def replace_keys(text, replacements_dict):
for key, var in replacements_dict.iteritems():
replacement = %s = %s % (key, var)
text = text.replace(key, replacement)
return text
# example of two lines of the file
str = \
structcn = 150.0
metfrac0 = 0.85
# replacements
replacement_dict = {structcn: 999.0, metfrac0: 0.85}
new_str = replace_keys(str, replacement_dict)
print str
print
print new_str
which produces...
structcn = 150.0
metfrac0 = 0.85
structcn = 999.0 = 150.0
metfrac0 = 0.85 = 0.85
thanks.
If the structure is very regular you can use something like this:
def replace_keys(text, replacements_dict):
lines=text.splitlines()
for i, row in enumerate(lines):
key, sep, val = row.split()
lines[i]= .join(
(key, sep, replacement_dict.get(key, val)))
return '\n'.join(lines)+'\n'
--
http://mail.python.org/mailman/listinfo/python-list
Re: Multiprocessing, shared memory vs. pickled copies
On 4/4/11 7:05 PM, Robert Kern wrote: On 4/4/11 3:20 PM, John Ladasky wrote: However, at least in Python 2.7, multiprocessing seems to have a C extension module defining the Connection objects. Unfortunately, it looks like this C extension just imports the regular pickler that is not aware of these custom types. That's why you get this error. I believe this is a bug in Python. So what did you try, and what output did you get? What version of Python are you using? I think that my understanding of multiprocessing needs to evolve beyond the use of Pool, but I'm not sure yet. This post suggests as much. http://mail.scipy.org/pipermail/scipy-user/2009-February/019696.html Maybe. If the __reduce_ex__() method is implemented properly (and multiprocessing bugs aren't getting in the way), you ought to be able to pass them to a Pool just fine. You just need to make sure that the shared arrays are allocated before the Pool is started. And this only works on UNIX machines. The shared memory objects that shmarray uses can only be inherited. I believe that's what Sturla was getting at. I'll take that back a little bit. Since the underlying shared memory types can only be shared by inheritance, the ForkingPickler is only used for the arguments passed to Process(), and not used for things sent through Queues (which Pool uses). Since Pool cannot guarantee that the data exists before the Pool starts its subprocesses, it must use the general mechanism. So in short, if you pass the shmarrays as arguments to the target function in Process(), it should work fine. -- Robert Kern I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth. -- Umberto Eco -- http://mail.python.org/mailman/listinfo/python-list
Re: is python 3 better than python 2?
On 4/5/2011 8:42 AM, neil wrote: what are the advantages? Py3 complete many transitions begun in Py2. In some cases, that means deleting old obsolete stuff, such as old-style classes. if it wasn't for python 3 breaking backwards compatibility would it be the better choice? Assuming equal library availability, absolutely. -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: is python 3 better than python 2?
On Apr 5, 6:42 am, neil neilharper300...@gmail.com wrote: what are the advantages? if it wasn't for python 3 breaking backwards compatibility would it be the better choice? I adopted Py3 because of support of OrderedDict and many new features. Since mine was a new project using no existing libraries, it made sense. -- Gnarlie -- http://mail.python.org/mailman/listinfo/python-list
Re: How to program in Python to run system commands in 1000s of servers
On Tue, Apr 5, 2011 at 7:51 AM, Babu bab...@gmail.com wrote: Here is my problem: Want to program in python to run sysadmin commands across 1000s of servers and gather the result in one place. Many times the commands need to be run as root. We cannot use ssh as root remote connectivity as well. What are the different ways of programming in python to achieve this? There are a bajillion ways to do it badly, but SSH sounds like the right tool for the job here. You really don't want your remote admin system compromised, and fabric makes this kind of thing really much less painful. Geremy Condra -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiprocessing, shared memory vs. pickled copies
Hi Philip,
Thanks for the reply.
On Apr 4, 4:34 pm, Philip Semanchuk phi...@semanchuk.com wrote:
So if you're going to use multiprocessing, you're going to use pickle, and you
need pickleable objects.
OK, that's good to know.
Pickling is still a pretty
vague progress to me, but I can see that you have to write custom
__reduce__ and __setstate__ methods for your objects.
Well, that's only if one's objects don't support pickle by default. A lot of
classes do without any need for custom __reduce__ and __setstate__ methods.
Since you're apparently not too familiar with pickle, I don't want you to get
the false impression that it's a lot of trouble. I've used pickle a number of
times and never had to write custom methods for it.
I used __reduce__ and __setstate__ once before with success, but I
just hacked at code I found on the Net, without fully understanding
it.
All right, since my last post, I've made an attempt to understand a
bit more about pickle. In doing so, I'm getting into the guts of the
Python class model, in a way that I did not expect. I believe that I
need to understand the following:
1) What kinds of objects have a __dict__,
2) Why the default pickling methods do not simply look for a __dict__
and serialize its contents, if it is present, and
3) Why objects can exist that do not support pickle by default, and
cannot be correctly pickled without custom __reduce__ and __setstate__
methods.
I can only furnish a (possibly incomplete) answer to question #1.
User subclasses apparently always have a __dict__. Here:
class Foo:
... pass # It doesn't get any simpler
...
x = Foo()
x
__builtin__.Foo instance at 0x9b916cc
x.__dict__
{}
x.spam = eggs
x.__dict__
{'spam': 'eggs'}
setattr(x, parrot, dead)
__builtin__.Bar instance at 0x9b916cc
dir(x)
['__doc__', '__module__', 'parrot', 'spam']
x.__dict__
{'parrot': 'dead', 'spam': 'eggs'}
x.__dict__ = {a:b, c:d}
dir(x)
['__doc__', '__module__', 'a', 'c']
x.__dict__
{'a': 'b', 'c': 'd'}
Aside: this finding makes me wonder what exactly dir() is showing me
about an object (all objects in the namespace, including methods, but
not __dict__ itself?), and why it is distinct from __dict__.
In contrast, it appears that BUILT-IN classes (numbers, lists,
dictionaries, etc.) do not have a __dict__. And that you can't force
a __dict__ into built-in objects, no matter how you may try.
n = 1
dir(n)
['__abs__', '__add__', '__and__', '__class__', '__cmp__',
'__coerce__',
'__delattr__', '__div__', '__divmod__', '__doc__', '__float__',
'__floordiv__',
'__format__', '__getattribute__', '__getnewargs__', '__hash__',
'__hex__',
'__index__', '__init__', '__int__', '__invert__', '__long__',
'__lshift__',
'__mod__', '__mul__', '__neg__', '__new__', '__nonzero__',
'__oct__', '__or__',
'__pos__', '__pow__', '__radd__', '__rand__', '__rdiv__',
'__rdivmod__',
'__reduce__', '__reduce_ex__', '__repr__', '__rfloordiv__',
'__rlshift__',
'__rmod__', '__rmul__', '__ror__', '__rpow__', '__rrshift__',
'__rshift__',
'__rsub__', '__rtruediv__', '__rxor__', '__setattr__',
'__sizeof__', '__str__',
'__sub__', '__subclasshook__', '__truediv__', '__trunc__',
'__xor__', 'conjugate',
'denominator', 'imag', 'numerator', 'real']
n.__dict__
File console, line 1, in module
''' type 'exceptions.AttributeError' : 'int' object has no
attribute '__dict__' '''
n.__dict__ = {a:b, c:d}
File console, line 1, in module
''' type 'exceptions.AttributeError' : 'int' object has no
attribute '__dict__' '''
setattr(n, __dict__, {a:b, c:d})
File console, line 1, in module
''' type 'exceptions.AttributeError' : 'int' object has no
attribute '__dict__' '''
This leads straight into my second question. I THINK, without knowing
for sure, that most user classes would pickle correctly by simply
iterating through __dict__. So, why isn't this the default behavior
for Python? Was the assumption that programmers would only want to
pickle built-in classes? Can anyone show me an example of a common
object where my suggested approach would fail?
What might be easier than fooling around with boxes of sharp knives is to
convert
your ndarray objects
... with their attendant meta-data, of course...
to Python lists. Lists are pickle-friendly and easy to turn
back into ndarray objects once they've crossed the pickle boundary.
That's a cute trick. I may try it, but I would rather do it the way
that Python recommends. I always prefer to understand what I'm doing,
and why.
Python will only get better at working with multiple cores/CPUs, but there's
plenty of room for improvement on the status quo.
Thank you for agreeing with me. I'm not formally trained in computer
science, and there was always the chance that my opinion as a non-
professional might come from simply not understanding the issues
Re: Suggest some exercises on Python
On 4/5/2011 9:13 AM, Jins Thomas wrote: I'm a new bie. I have just started learning Python (3.0), Please download, install, and use 3.2. finished with official tutorial. I would like to have your opinion on some 1. Good books (for an intermediate in programming) with lot's of ... 2. Or any link or site which suggests some exercises to do in Python. ... One thing I did was lots of experiments with variations on the example given in the doc, and creation of examples that are not. After 14 years, I still do that with a new-to-me module. I nearly always use the IDLE interpreter window (for one-liners) or editor windows. That said, the problem with such requests is that the proper answer depends what your are interested in. Suppose you are interested in numerical computing. Pick any book numerical algorithms or analysis and pick some examples with answers given. Most likely, the book uses some combination of natural language, pseudocode, and Fortran or C. Rewrite in Python, testing with the inputs and outputs given (keeping in mind that floating point answers will vary in the last digits). Suppose you are more interested in interacting with the web. Write something to fetch a page (from python.org, say) and do something with it. Try filling out the search form at bugs.python.org and extracting the data table from the response page. Etc. Suppose you are even move interested in xyz. make up something to do here -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: Suggest some exercises on Python
On Tue, 05 Apr 2011 13:18:19 -0400, Terry Reedy wrote: On 4/5/2011 9:13 AM, Jins Thomas wrote: I'm a new bie. I have just started learning Python (3.0), Please download, install, and use 3.2. To elaborate further: Python 3.0 is not supported, and is buggy and slow. You should avoid it. Python 3.1 is the first production-ready version of Python 3, and 3.2 is the current version. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: Light weight IDE like pywin for os x 10.6
python wrote: I have looked a while for this answer. Sorry if it right before me. I have move from Windows to os x. The thing I miss most is pywin. I know you can purchase or download full IDE's for python or even use Eclipse. I really liked the ability to switch from interactive interpreter to editor easily. The autocompletion is very helpful so idle does not quite cut it for me. How about eric (http://eric-ide.python-projects.org)? Detlev -- Detlev Offenbach det...@die-offenbachs.de -- http://mail.python.org/mailman/listinfo/python-list
Re: Suggest some exercises on Python
On Tue, Apr 5, 2011 at 6:13 AM, Jins Thomas jinstho...@gmail.com wrote: Hi all, I'm a new bie. I have just started learning Python (3.0), finished with official tutorial. I would like to have your opinion on some 1. Good books (for an intermediate in programming) with lot's of exercise i can try it out. For example when i started with Perl i was going through a book 'Learning Perl' and it contained lots of exercises which made me confident. 2. Or any link or site which suggests some exercises to do in Python. When i was looking for some similar threads in some sites, they propose some sites which gives some exercises and puzzles to solve in python. But i'm feeling it's too much complicated for my capability. If you're mathematically inclined, try Project Euler. It isn't python-specific, but it is a lot of fun. http://projecteuler.net/ Geremy Condra -- http://mail.python.org/mailman/listinfo/python-list
Re: Fun python 3.2 one-liner
On Wed, 06 Apr 2011 01:19:06 +1000, Chris Angelico wrote: On Wed, Apr 6, 2011 at 1:07 AM, Steven D'Aprano steve+comp.lang.pyt...@pearwood.info wrote: On Tue, 05 Apr 2011 15:38:28 +0200, Daniel Fetchinson wrote: Seriously, who would want to limit him/herself to 80 characters in 2011? Seriously, or is that a rhetorical question? People who like to have two source files side-by-side on a standard sized monitor, or three on a wide-screen monitor. And most importantly... people who want to have their code accepted into the Python standard library. Is that 80 including indentation, or excluding? And if including, does that put a hard limit of 20 indentation levels for standard library code? Including. As for the hard limit, pretty much. Only partly tongue-in-cheek. I have code that quite legitimately has gone to ten tabs in, and stayed there, Legitimately? I very much doubt it. (Only half joking.) and has on occasion gone as far as 12-16. I would consider anything more than four indents a code smell. That is, four is unexceptional; five would make me look over the code to see if it could be refactored; six would make me look at it *carefully*; eight would have me questioning my own sanity. I wouldn't give a hard limit beyond which I would never go beyond, but I find it difficult to imagine what drugs I'd need to be on to go beyond eight. *wink* -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: Fun python 3.2 one-liner
what is the character limit on a one liner :P. For PEP 8 compliance, 80 characters. :-) Yeah, but we don't live in the 80's or 90's anymore and our screens can support xterms (or let alone IDE widows) much wider than 80 characters. I'm using 140 for python these days. Seriously, who would want to limit him/herself to 80 characters in 2011? Seriously, or is that a rhetorical question? Rhetorical :) What it intended to demonstrate is that it is possible to rationalize ancient habits which have their origins in particular circumstances of those ancient times but actually nothing necessitates them today other than the momentum built around them during their lifetime (which is a pretty strong argument for them by the way). Cheers, Daniel People who like to have two source files side-by-side on a standard sized monitor, or three on a wide-screen monitor. People who need to read or edit source code on a virtual terminal rather than in a GUI console app. People who print out source code to read later. People with poor vision who need to use a significantly larger sized characters, and therefore can't fit as many on a line. People who might want to email code snippets without having them inconveniently wrapped by the mail client. People who don't like reading really long, overly complex, lines, and prefer to keep lines short for readability. And most importantly... people who want to have their code accepted into the Python standard library. Personally, I find that the discipline of keeping to 80 characters is good for me. It reduces the temptation of writing obfuscated Python one- liners when two lines would be better. The *only* time it is a burden is when I write doc strings, and even then, only a small one. -- Steven -- http://mail.python.org/mailman/listinfo/python-list -- Psss, psss, put it down! - http://www.cafepress.com/putitdown -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiprocessing, shared memory vs. pickled copies
On Apr 5, 2011, at 12:58 PM, John Ladasky wrote: Hi Philip, Thanks for the reply. On Apr 4, 4:34 pm, Philip Semanchuk phi...@semanchuk.com wrote: So if you're going to use multiprocessing, you're going to use pickle, and you need pickleable objects. OK, that's good to know. But as Dan Stromberg pointed out, there are some pickle-free ways to communicate between processes using multiprocessing. This leads straight into my second question. I THINK, without knowing for sure, that most user classes would pickle correctly by simply iterating through __dict__. So, why isn't this the default behavior for Python? Was the assumption that programmers would only want to pickle built-in classes? One can pickle user-defined classes: class Foo(object): ... pass ... import pickle foo_instance = Foo() pickle.dumps(foo_instance) 'ccopy_reg\n_reconstructor\np0\n(c__main__\nFoo\np1\nc__builtin__\nobject\np2\nNtp3\nRp4\n.' And as Robert Kern pointed out, numpy arrays are also pickle-able. import numpy pickle.dumps(numpy.zeros(3)) cnumpy.core.multiarray\n_reconstruct\np0\n(cnumpy\nndarray\np1\n(I0\ntp2\nS'b'\np3\ntp4\nRp5\n(I1\n(I3\ntp6\ncnumpy\ndtype\np7\n(S'f8'\np8\nI0\nI1\ntp9\nRp10\n(I3\nS''\np11\nNNNI-1\nI-1\nI0\ntp12\nbI00\nS'\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00'\np13\ntp14\nb. As a side note, you should always use new style classes, particularly since you're exploring the details of Python class construction. New is a bit a of misnomer now, as new style classes were introduced in Python 2.2. They have been the status quo in Python 2.x for a while now and are the only choice in Python 3.x. Subclassing object gives you a new style class: class Foo(object): Not subclassing object (as you did in your example) gives you an old style class: class Foo: Cheers Philip -- http://mail.python.org/mailman/listinfo/python-list
Indentation levels and line lengths (was Re: Fun python 3.2 one-liner)
On Wed, Apr 6, 2011 at 3:48 AM, Steven D'Aprano
steve+comp.lang.pyt...@pearwood.info wrote:
and has on occasion gone as far as 12-16.
I would consider anything more than four indents a code smell. That is,
four is unexceptional; five would make me look over the code to see if it
could be refactored; six would make me look at it *carefully*; eight
would have me questioning my own sanity. I wouldn't give a hard limit
beyond which I would never go beyond, but I find it difficult to
imagine what drugs I'd need to be on to go beyond eight.
*wink*
Chocolate. Chocolate and heavy C code work. The alternative is to
break everything out into separate functions, which inevitably results
in heaps of unnecessary parameter-passing; granted, a C compiler will
often optimize most of it away, but it's still annoying to have to
pass a whole lot of reference parameters to a function that's only
ever called from one place.
As an example, think of a typical GUI message loop (in OS/2 or Windows):
int WndProc(HWND hwnd,int msg,int param1,int param2)
{
switch (msg)
{
case WM_PAINT:
{
if (have_message)
{
display_message();
y+=msg_height;
}
}
//etc, etc, etc
default: return 0;
}
}
That's four levels of indentation right there. Now imagine that the
whole kaboodle is inside a class definition and that's a fifth, and
then it only takes a small amount of extra code complexity to hit
eight. I agree that it's a code smell, though. For something to get to
the 10 or 12 that I mentioned above, it really has to be something
with a whole lot of relatively insignificant indentations early on, so
the entire useful logic is contained in levels 6-10 or something;
and the 16 was probably a little artificial, in that I *could* have
refactored that function but just never got around to it (which means
it's pushing the limits of legitimately). But I know I've had C code
get past 10 without there being any logical reason to break some of
the code out.
The other time I have miles of indentation is when I'm working in an
unfamiliar language, and I'm not comfortable with its variable scoping
rules (hello there, PHP). That's not what I'd call legitimate
indentation, but I sure am glad there's no hard limit on what's
accepted.
Chris Angelico
--
http://mail.python.org/mailman/listinfo/python-list
Re: Suggest some exercises on Python
On 05/04/2011 18:24, Steven D'Aprano wrote: On Tue, 05 Apr 2011 13:18:19 -0400, Terry Reedy wrote: On 4/5/2011 9:13 AM, Jins Thomas wrote: I'm a new bie. I have just started learning Python (3.0), Please download, install, and use 3.2. To elaborate further: Python 3.0 is not supported, and is buggy and slow. You should avoid it. Python 3.1 is the first production-ready version of Python 3, and 3.2 is the current version. You can always go back to 2.7 when you realise that something you want to use is not yet fully supported, in my case matplotlib. Mark L. -- http://mail.python.org/mailman/listinfo/python-list
Re: is python 3 better than python 2?
On 4/5/2011 7:46 AM, Mel wrote: neil wrote: what are the advantages? if it wasn't for python 3 breaking backwards compatibility would it be the better choice? IMHO the killer app for Python 3 is in more reasonable support for foreign character sets (no matter where your are, at least one out of the hundred-odd Unicode character sets is going to be foreign,) and generally internationalized data processing. Well, actually Unicode support went in back around Python 2.4. In 3.x, ASCII strings went away, but that was more of a removal. John Nagle -- http://mail.python.org/mailman/listinfo/python-list
a better way to invert a list?
Greetings, I've been playing around (in Python 3.1) with permutations of 0,1,...,n-1, represented by lists, p, of length n, where p[i] = the image of i under the permutation. I wanted to be able to calculate the inverse of such a permutation, and came up with the following succint but not quite readable function: def invert(p): return [ j for (i,j) in sorted(zip(p,range(len(p] I rejected the obvious [p.index(i) for i in range(len(p))] since that seems an inefficient way to sort. Is there a better way to do this? Another question about my code: What is more idiomatic, [ j for (i,j) in ...] or [ x[1] for x in ... ]? I find the former more readable. But it makes bindings for i and doesn't use them - which can't be very efficient. In Haskell or ML, you can use patterns that contain wild cards that play a role in the pattern-matching but don't establish any binding. Can that be done in Python? Thanks -- http://mail.python.org/mailman/listinfo/python-list
Re: a better way to invert a list?
On Tue, Apr 5, 2011 at 3:17 PM, scattered tooscatte...@gmail.com wrote: Greetings, I've been playing around (in Python 3.1) with permutations of 0,1,...,n-1, represented by lists, p, of length n, where p[i] = the image of i under the permutation. I wanted to be able to calculate the inverse of such a permutation, and came up with the following succint but not quite readable function: def invert(p): return [ j for (i,j) in sorted(zip(p,range(len(p] I rejected the obvious [p.index(i) for i in range(len(p))] since that seems an inefficient way to sort. Is there a better way to do this? Instead of zipping up range(len(p)), you could use the more Pythonic enumerate: def invert(p): return [i for (i, j) in sorted(enumerate(p), key=operator.itemgetter(1))] The main advantage here is that it will accept an iterator for p, not just a sequence. But it's still O(n log n ) due to the sort. More efficient would be: def invert(p): inverse = [None] * len(p) for (i, j) in enumerate(p): inverse[j] = i return inverse Which is O(n). If that is too verbose, you could also use a dictionary: def invert(p): return dict(map(reversed, enumerate(p))) But the disadvantage here is that if you want to iterate over the result in order, you're back to either having to sort it or doing something ugly like this: q = invert(p) for i in range(len(q)): # Do something with q[i] Another question about my code: What is more idiomatic, [ j for (i,j) in ...] or [ x[1] for x in ... ]? I find the former more readable. But it makes bindings for i and doesn't use them - which can't be very efficient. I don't know of any reason to prefer one over the other. One convention for unpacking values that aren't used is to name the variable '_'. But this doesn't help efficiency at all; it's just a convention to inform somebody reading the code that the value is ignored. In Haskell or ML, you can use patterns that contain wild cards that play a role in the pattern-matching but don't establish any binding. Can that be done in Python? No, unfortunately. Cheers, Ian -- http://mail.python.org/mailman/listinfo/python-list
Re: replace regex in file using a dictionary
yes thanks both work nicely, I will ponder the suggestions. -- http://mail.python.org/mailman/listinfo/python-list
Re: a better way to invert a list?
On Apr 5, 5:46 pm, Ian Kelly ian.g.ke...@gmail.com wrote: On Tue, Apr 5, 2011 at 3:17 PM, scattered tooscatte...@gmail.com wrote: Greetings, I've been playing around (in Python 3.1) with permutations of 0,1,...,n-1, represented by lists, p, of length n, where p[i] = the image of i under the permutation. I wanted to be able to calculate the inverse of such a permutation, and came up with the following succint but not quite readable function: def invert(p): return [ j for (i,j) in sorted(zip(p,range(len(p] I rejected the obvious [p.index(i) for i in range(len(p))] since that seems an inefficient way to sort. Is there a better way to do this? Instead of zipping up range(len(p)), you could use the more Pythonic enumerate: def invert(p): return [i for (i, j) in sorted(enumerate(p), key=operator.itemgetter(1))] Seems a bit kludgy - isn't their any more direct way to sort by the second element in a list of tuples? I gather that this is one area where Python 3 differs from earlier Pythons - but I never had much experience with Python 2 to compare it with. The main advantage here is that it will accept an iterator for p, not just a sequence. But it's still O(n log n ) due to the sort. More efficient would be: def invert(p): inverse = [None] * len(p) for (i, j) in enumerate(p): inverse[j] = i return inverse Elegant. This seems like the best solution, although it isn't as much fun to write as a one-liner. Thanks Which is O(n). If that is too verbose, you could also use a dictionary: def invert(p): return dict(map(reversed, enumerate(p))) But the disadvantage here is that if you want to iterate over the result in order, you're back to either having to sort it or doing something ugly like this: q = invert(p) for i in range(len(q)): # Do something with q[i] Another question about my code: What is more idiomatic, [ j for (i,j) in ...] or [ x[1] for x in ... ]? I find the former more readable. But it makes bindings for i and doesn't use them - which can't be very efficient. I don't know of any reason to prefer one over the other. One convention for unpacking values that aren't used is to name the variable '_'. But this doesn't help efficiency at all; it's just a convention to inform somebody reading the code that the value is ignored. In Haskell or ML, you can use patterns that contain wild cards that play a role in the pattern-matching but don't establish any binding. Can that be done in Python? No, unfortunately. Cheers, Ian -- http://mail.python.org/mailman/listinfo/python-list
Re: a better way to invert a list?
[Ian Kelly] Which is O(n). If that is too verbose, you could also use a dictionary: def invert(p): return dict(map(reversed, enumerate(p))) def inv(p): return dict(zip(p, itertools.count())) Raymond -- http://mail.python.org/mailman/listinfo/python-list
Re: Fun python 3.2 one-liner
On Apr 5, 6:38 am, Daniel Fetchinson fetchin...@googlemail.com wrote: what is the character limit on a one liner :P. For PEP 8 compliance, 80 characters. :-) Yeah, but we don't live in the 80's or 90's anymore and our screens can support xterms (or let alone IDE widows) much wider than 80 characters. I'm using 140 for python these days. Seriously, who would want to limit him/herself to 80 characters in 2011? I wonder how many people will shorten otherwise clear variable names just to get their lines to fit in 80 characters? Raymond -- http://mail.python.org/mailman/listinfo/python-list
Re: 3D subfigures in matplotlib?
On Tuesday, April 5, 2011 6:17:34 AM UTC-4, MATLABdude wrote: How can I make maybe 3D subfigures with Python and matplotlib? I found the following example (http://matplotlib.sourceforge.net/ examples/mplot3d/subplot3d_demo.html), but it doesn't work. [snip] I am using Python 2.6.6., and matplotlib 0.99.3. How can I make several subfigures in 3D? The demo works fine for me using Matplotlib 1.0.1. Here's a version that should work on your older version of Matplotlib. Instead of adding a subplot with projection='3d', it adds a normal subplot and gets the bounding rectangle. The rectangle is used to configure the Axes3D instance: from mpl_toolkits.mplot3d.axes3d import Axes3D import matplotlib.pyplot as plt # imports specific to the plots in this example import numpy as np from matplotlib import cm from mpl_toolkits.mplot3d.axes3d import get_test_data fig = plt.figure(figsize=(9.5,5.0)) # First subplot rect = fig.add_subplot(1, 2, 1).get_position() ax = Axes3D(fig, rect) X = np.arange(-5, 5, 0.25) Y = np.arange(-5, 5, 0.25) X, Y = np.meshgrid(X, Y) R = np.sqrt(X**2 + Y**2) Z = np.sin(R) surf = ax.plot_surface(X, Y, Z, rstride=1, cstride=1, cmap=cm.jet, linewidth=0, antialiased=False) ax.set_zlim3d(-1.01, 1.01) fig.colorbar(surf, shrink=0.5, aspect=10) # Second subplot rect = fig.add_subplot(1, 2, 2).get_position() ax = Axes3D(fig, rect) X, Y, Z = get_test_data(0.05) ax.plot_wireframe(X, Y, Z, rstride=10, cstride=10) plt.show() -- http://mail.python.org/mailman/listinfo/python-list
Re: How to program in Python to run system commands in 1000s of servers
In article mailman.52.1302022780.9059.python-l...@python.org, geremy condra debat...@gmail.com wrote: On Tue, Apr 5, 2011 at 7:51 AM, Babu bab...@gmail.com wrote: Here is my problem: Want to program in python to run sysadmin commands across 1000s of servers and gather the result in one place. Many times the commands need to be run as root. We cannot use ssh as root remote connectivity as well. What are the different ways of programming in python to achieve this? There are a bajillion ways to do it badly, but SSH sounds like the right tool for the job here. You really don't want your remote admin system compromised, and fabric makes this kind of thing really much less painful. Agreed on the fabric (fabfile.org) recommendation. We've been using it for about 6 months. Very handy. I'm not sure how to parse: We cannot use ssh as root remote connectivity as well. but with 1000's of servers, I really don't see any alternative to ssh, with key authentication. You don't really propose to type passwords at 1000's of machines, do you? As far as fabric goes, it's not perfect, but it's pretty good and if you try to roll your own alternative, you will likely 1) waste a lot of time and money and 2) end up with an inferior solution. -- http://mail.python.org/mailman/listinfo/python-list
Sandboxed Python: memory limits?
Is it possible, and if so is it easy, to limit the amount of memory an embedded Python interpreter is allowed to allocate? I don't want to ulimit/rlimit the process if I don't have to (or rather, I want the process's limit to be high, and the Python limit much lower), but just to force Python to throw MemoryError sooner than it otherwise would (my code can then graciously deal with the exception). Google turned up this thread: http://stackoverflow.com/questions/1760025/limit-python-vm-memory The answers given include resource.setrlimit (which presumably goes straight back to the API, which will affect the whole process), and a simple counter (invasive to the code). But I want something that I can impose from the outside. I have a vague memory of reading somewhere that it's possible to replace the Python memory allocator. This would be an option, if there's no simple way to say your maximum is now 16MB, but I now can't find it back. Was I hallucinating? Hoping not to reinvent any wheels today! Thanks! Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list
Standard config file format
I am working on a program to monitor directory file changes and am would like a configuration file. This file would specify email addresses, file and directory locations.. Is there a preferred format to use with python? -- Thanks Vincent Davis -- http://mail.python.org/mailman/listinfo/python-list
Re: Standard config file format
On Tue, Apr 5, 2011 at 7:16 PM, Vincent Davis vinc...@vincentdavis.net wrote: I am working on a program to monitor directory file changes and am would like a configuration file. This file would specify email addresses, file and directory locations.. Is there a preferred format to use with python? ConfigParser supports an INI-like format: http://docs.python.org/library/configparser.html JSON is also a popular option: http://docs.python.org/library/json.html Cheers, Chris -- http://mail.python.org/mailman/listinfo/python-list
Re: Fun python 3.2 one-liner
Raymond Hettinger pyt...@rcn.com writes: On Apr 5, 6:38 am, Daniel Fetchinson fetchin...@googlemail.com wrote: Yeah, but we don't live in the 80's or 90's anymore and our screens can support xterms (or let alone IDE widows) much wider than 80 characters. I'm using 140 for python these days. Seriously, who would want to limit him/herself to 80 characters in 2011? A broadsheet newspaper allows a whole lot of characters on a single line, yet they still limit the width of each passage of text. The limit on line length is not only for technical reasons, but for readability. I wonder how many people will shorten otherwise clear variable names just to get their lines to fit in 80 characters? Not me. When the line is over 78 characters or so, I just break the line at an appropriate point. Line breaks (within bracketing syntax) are far less expensive than uncommunicative variable names. -- \ “I must have a prodigious quantity of mind; it takes me as much | `\ as a week sometimes to make it up.” —Mark Twain, _The Innocents | _o__) Abroad_ | Ben Finney -- http://mail.python.org/mailman/listinfo/python-list
Re: Python benefits over Cobra
On 05-Apr-11 06:22 AM, Brendan Simon (eTRIX) wrote: Any other arguments where Python has benefits over Cobra ?? Cheers, Brendan. Two questions: 1. Is Cobra Open Source? 2. The blog ended on October, did he run out of steam? I liked the '.', in place of '.self', but that's been rejected for Python. Cobra is an open source project under the MIT license. according to the web site. It seems that it mostly, if not all, the work of one person. All code commits seem to be from Charles Esterbrook. It seems the latest release is Oct 2010, but I can see posts in the forum for April 2011, March, Feb, . I too like the '.' in place of self :) However, I don't like _ as line continuation :( Life is tough, eh ?? It also looks like there is work to have it run in a JVM. I presume that means that no .NET/Mono framework is required ?? -- http://mail.python.org/mailman/listinfo/python-list
How to debug c libraries on python?
Hi, everyone: I encouter a problem: I invoke some c libraries in python through the api CDLL.Possibly, there is sth. wrong in my c libraries. It would appear segment fault when executing some func in c libraries which invoked through CDLL. How can I debug? I attempted to debug it with pdb, but this is not the problem of python, the fault belongs to c. How can I do? thanks, yuanzheng. -- http://mail.python.org/mailman/listinfo/python-list
Re: is python 3 better than python 2?
On 4/5/2011 4:42 PM, John Nagle wrote: Well, actually Unicode support went in back around Python 2.4. Even earlier, I think, but there were and still are problems with unicode in 2.x. Some were and will only be fixed in 3.x. In 3.x, ASCII strings went away, but that was more of a removal. Yes and no. They were kept slightly modified as bytes, with all of the string methods kept. -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
[issue11734] Add half-float (16-bit) support to struct module
Eli Stevens wickedg...@gmail.com added the comment:
I see the distinction about the rounding error now. Thanks for clarifying;
I've added more tests as suggested.
Looking at _struct.c, line 2085:
/* Skip float and double, could be
unknown float format */
if (ptr-format == 'd' || ptr-format == 'f')
break;
ptr-pack = native-pack;
ptr-unpack = native-unpack;
break;
I'm going to assume that it's okay to allow 'e' to pass through here, since the
'e' type is *always* going to be in IEEE 754 (not unknown) floating point
format, and the handling routines don't rely on the C conversions the way the
float/double ones do. Is that a good assumption to make?
Also, looking at the line in the native_table declaration:
{'e', sizeof(short), SHORT_ALIGN,nu_halffloat, np_halffloat},
Does it make sense to have an entry here since there isn't actually a native
representation? ATM it's implemented as just figuring out the platform
endianness, and then calling the corresponding lp_/lu_ or bp_/bu_ function.
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[issue11734] Add half-float (16-bit) support to struct module
Eli Stevens wickedg...@gmail.com added the comment: More questions: The current _PyFloat_Pack4 doesn't round to even: fbits = (unsigned int)(f + 0.5); /* Round */ Is the mismatch going to be a problem? Should I change the _PyFloat_Pack4 implementation while I'm in there? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11734 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11725] httplib and urllib2 failed ssl connection httplib.BadStatusLine
Ronald Oussoren ronaldousso...@mac.com added the comment: Ned: we could work around this platform issue by including openssl 1.0d in the OSX installer. I'm not sure if that's acceptable for a bugfix release though. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11725 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11747] unified_diff function product incorrect range information
ysj.ray ysj@gmail.com added the comment: Since if one of the two comparing files is empty, gnu diff regards the beginning line of differences as line 0 (there is not any lines), but difflib regards it as line 1(there is a line, but empty). Not sure weather is correct since the practice usage of diff output is feeding it to patch program which determine the different line location mostly based on context identical lines instead of the line numbers in the hunk headers, so it doesn't matter weather it's line 0 or line 1. But it is still better to keep consist with gnu diff. In context_diff() it is correct since if there is less then 2 different lines in a hunk, only ending line number is display in hunk header. Here is a patch which fix this. -- keywords: +patch nosy: +ysj.ray type: - behavior versions: +Python 3.1, Python 3.2, Python 3.3 Added file: http://bugs.python.org/file21539/issue_11747.diff ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11747 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11764] inspect.getattr_static code execution w/ class body as non dict
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[issue2736] datetime needs an epoch method
Marc-Andre Lemburg m...@egenix.com added the comment: Just to add another data point to this discussion: mxDateTime, which in large parts inspired the Python datetime module, has had a .ticks() method (for local time) and a .gmticks() method (for UTC) for more than a decade now and so far, I haven't seen a single complaint about any of the issues raised in this discussion. The methods naturally return the Unix ticks value as float, since that's what the time module uses as basis and the whole purpose of those methods is to make interaction with the time module easy and straight-forward. Likewise, the epoch is also the same as the time module's one. Victor's patch could easily be updated to return floats as well, to make it compatible with the time module. There's only one catch that Victor's patch doesn't include: mktime() doesn't always work with DST set to anything but -1. mxDateTime checks the API at module load time and then determines whether it can be used with a DST setting or not (see the mxDateTime code for details). Not sure whether today's mktime() implementations still have any issues with this, but it's better to double-check than to get wrong results. http://www.egenix.com/products/python/mxBase/mxDateTime/ -- nosy: +lemburg ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue2736 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue2736] datetime needs an epoch method
STINNER Victor victor.stin...@haypocalc.com added the comment: Marc, could you maybe write a new patching taking care of the DST and maybe also the timezone? It looks like you have a long experience in timestamps :-) -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue2736 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11703] Bug in python = 2.7 with urllib2 fragment
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[issue11707] Create C version of functools.cmp_to_key()
Roundup Robot devnull@devnull added the comment: New changeset a03fb2fc3ed8 by Raymond Hettinger in branch 'default': Issue #11707: Fast C version of functools.cmp_to_key() http://hg.python.org/cpython/rev/a03fb2fc3ed8 -- nosy: +python-dev ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11707 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue2736] datetime needs an epoch method
Marc-Andre Lemburg m...@egenix.com added the comment: STINNER Victor wrote: STINNER Victor victor.stin...@haypocalc.com added the comment: Marc, could you maybe write a new patching taking care of the DST and maybe also the timezone? It looks like you have a long experience in timestamps :-) Sorry, but no. I'm not really a fan of the datetime module and try to stay away from it whenever I can :-) Note that dealing with DST in timezones other than the local time zone, is bound to go wrong without direct access to the tz library. The C lib doesn't provide any good way to access timezone information other than the local timezone or UTC. When dealing with date/time values, it is usually best to stay with UTC and only transform those values into local times in user interfaces on the front-end client. Consequently, I'd suggest to only allow UTC and local timezone conversions for the method in the datetime module. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue2736 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11707] Create C version of functools.cmp_to_key()
Raymond Hettinger raymond.hettin...@gmail.com added the comment: Thanks for the patch Filip. Closing this. If anyone wants to lobby the RM for a 3.2 backport, feel free to re-open and assign to the release manager for consideration. -- status: open - closed ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11707 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11734] Add half-float (16-bit) support to struct module
Eli Stevens wickedg...@gmail.com added the comment: Made the _PyFloat_Pack2 match the algo in _PyFloat_Pack4, and did similar for Unpack. This should work on platforms that don't have IEEE 754 floats except for situations where an INF or NAN is unpacked (this is the same as the Unpack4 behavior). This also gets rid of any need for #ifdef'd code (an ad-hoc speed test showed no noticeable difference between the numpy-based version and the CPython-based version of the functions). I've also added a bit of documentation to this version, as well as more tests. I haven't changed anything about the native_table entry or Pack4's non-round-to-even behavior. -- Added file: http://bugs.python.org/file21540/cpython-struct-float16-v4.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11734 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11707] Create C version of functools.cmp_to_key()
Roundup Robot devnull@devnull added the comment: New changeset 76ed6a061ebe by Victor Stinner in branch 'default': Issue #11707: Fix compilation errors with Visual Studio http://hg.python.org/cpython/rev/76ed6a061ebe -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11707 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11707] Create C version of functools.cmp_to_key()
STINNER Victor victor.stin...@haypocalc.com added the comment:
functools_cmp_to_key() doesn't check that the argument is a callable.
table=list(range(3))
table.sort(key=functools.cmp_to_key(3))
Traceback (most recent call last):
File stdin, line 1, in module
TypeError: 'int' object is not callable
PyCallable_Check() should be used, something like:
if (!PyCallable_Check(cmp)) {
PyErr_SetString(PyExc_TypeError, parameter must be callable);
return NULL;
}
--
nosy: +haypo
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[issue11766] test_multiprocessing failure (test_pool_worker_lifetime)
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[issue11707] Create C version of functools.cmp_to_key()
Raymond Hettinger raymond.hettin...@gmail.com added the comment: functools_cmp_to_key() doesn't check that the argument is a callable. I don't think that is necessary; it will fail with a TypeError when the attempt is made to call it. This is the approach we take elsewhere (look at the built-in filter() function for example). That being said, if you really think the early check is necessary, feel free to check it in. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11707 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11277] test_zlib.test_big_buffer crashes under BSD (Mac OS X and FreeBSD)
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[issue11757] test_subprocess.test_communicate_timeout_large_ouput failure on select(): negative timeout?
Changes by STINNER Victor victor.stin...@haypocalc.com: -- title: test_subprocess failure - test_subprocess.test_communicate_timeout_large_ouput failure on select(): negative timeout? ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11757 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11770] inspect.dir_static
New submission from Michael Foord mich...@voidspace.org.uk: A version of dir that returns all the members that can be seen by getattr_static. -- assignee: michael.foord components: Library (Lib) messages: 133017 nosy: michael.foord priority: low severity: normal stage: needs patch status: open title: inspect.dir_static type: behavior versions: Python 3.3 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11770 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11757] test_subprocess.test_communicate_timeout_large_ouput failure on select(): negative timeout?
Roundup Robot devnull@devnull added the comment: New changeset 3664fc29e867 by Victor Stinner in branch 'default': Issue #11757: subprocess ensures that select() and poll() timeout = 0 http://hg.python.org/cpython/rev/3664fc29e867 -- nosy: +python-dev ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11757 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9390] Error in sys.excepthook on windows when redirecting output of the script
Michal Molhanec molha...@gmail.com added the comment: I've got the same problem with 2.7.1 (both 32bit and 64bit versions) under W7 SP1 64bit. Under WXP SP3 32bit it works OK. What's worse the output file is empty. 3.2 (tested 64bit version) behaves even worse -- it does not print the error like 2.7 but the resulting file is empty as well! -- nosy: +Michal.Molhanec ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9390 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1692335] Fix exception pickling: Move initial args assignment to BaseException.__new__
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[issue11734] Add half-float (16-bit) support to struct module
Mark Dickinson dicki...@gmail.com added the comment: There's no disagreement, since they're different cases. [...] What he said. Should I change the _PyFloat_Pack4 implementation while I'm in there? No; let's keep the patch as simple as possible. We can open a separate issue for fixing _Pack4 if necessary. Is the failure to round-to-even only for legacy formats, or is it for IEEE formats as well? If the former, it's difficult to care much; if the latter, it should definitely be fixed, but not as part of this issue. Made the _PyFloat_Pack2 match the algo in _PyFloat_Pack4, and did similar for Unpack. Thanks; haven't looked at the new patch yet, but hope to do so in the next few days. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11734 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11771] hashlib object cannot be pickled
New submission from STINNER Victor victor.stin...@haypocalc.com:
$ ./python
Python 3.3a0 (default:76ed6a061ebe, Apr 5 2011, 12:25:00)
import hashlib, pickle
hash=hashlib.new('md5')
pickle.dumps(hash)
Traceback (most recent call last):
File stdin, line 1, in module
_pickle.PicklingError: Can't pickle class '_hashlib.HASH': attribute lookup
_hashlib.HASH failed
The problem is that _hashlib.HASH is not accessible at Python level. There is a
C define to make it accessible, but it is disabled by default: #if
HASH_OBJ_CONSTRUCTOR. This test is as old as the _hashlib module (#1121611,
624918e1c1b2).
--
components: Library (Lib)
messages: 133021
nosy: haypo
priority: normal
severity: normal
status: open
title: hashlib object cannot be pickled
versions: Python 3.3
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[issue11605] EMail generator.flatten() disintegrates over non-ascii multipart/alternative
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[issue11771] hashlib object cannot be pickled
STINNER Victor victor.stin...@haypocalc.com added the comment: Oh, I don't know if it is possible to serialize a OpenSSL hash object (EVP_MD_CTX)... -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11771 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9592] Limitations in objects returned by multiprocessing Pool
STINNER Victor victor.stin...@haypocalc.com added the comment:
1) A multiprocessing worker can not return (return, not raise!) an
Exception. (...) raise an error if multiple arguments are required:
TypeError: ('__init__() takes exactly 2 arguments (1 given)',
class '__main__.MyException', ())
This problem comes from pickle, not multiprocessing: issue #1692335.
2) A multiprocessing worker can not return an hashlib Object.
If this is attempted, pickle returns an error:
It is related to pickle and hashlib: #11771
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[issue11734] Add half-float (16-bit) support to struct module
Mark Dickinson dicki...@gmail.com added the comment: Is the failure to round-to-even only for legacy formats, or is it for IEEE formats as well? Ah; I see it's just for the non-IEEE formats, so not really an issue. When the float format is known, the code just depends on a (float) cast doing the right thing, which it generally will. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11734 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11734] Add half-float (16-bit) support to struct module
Mark Dickinson dicki...@gmail.com added the comment: I'd also suggest adding some more to the test suite here to verify that ties are rounding to the nearest even properly. And I second this suggestion. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11734 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue10977] Concrete object C API needs abstract path for subclasses of builtin types
Nick Coghlan ncogh...@gmail.com added the comment: I may have found another use case for this functionality. Currently, the Python code in heapq.py accepts arbitrary sequences (that are sufficiently compatible with the Sequence ABC), but the C code in _heapq only permits use of a concrete list. The two currently available approaches to address that discrepancy are: 1. Use PyObject_* calls instead of PyList_* calls throughout the code (yuck, we'd be making the common case significantly worse in the name of semantic purity) 2. Sprinkle type checks throughout the _heapq code to decide whether or not to call the concrete APIs or their abstract equivalents The extensive use of the PyList macro API in _heapq means that a little bit of 2 might still be necessary even if the concrete API was updated as Raymond suggests, but I think there would be value in changing the meaning of the concrete APIs to include falling back to the abstract APIs if the type assumption is incorrect. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue10977 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue10977] Concrete object C API needs abstract path for subclasses of builtin types
Nick Coghlan ncogh...@gmail.com added the comment: I added a few commments on Daniel's draft patch. However, I'm getting nervous about the performance impact of all these extra pointer comparisons. We should probably hold off on this until more of the macro benchmark suite runs on Py3k so we can get as hint as to the possible speed impact on real application code. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue10977 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue975330] Inconsistent newline handling in email module
R. David Murray rdmur...@bitdance.com added the comment: Well, it's two years later, but I did look at this during the sprints at PyCon, though I didn't get as far as posting it then (I only just now rediscovered the patch on my laptop). Python3 no longer has a binary flag on base64mime.encode, so here is a proposed patch for Python3. I'm not sure if this should be backported or not, but I'm leaning that way. Theoretically it should be only an improvement, but I can easily imagine unix-only programs unknowingly depending on the previous non-translation of newlines. Still, since email is about intermachine communication and this clearly makes it more RFC compliant, the change is a legitimate bug fix and the chance of breakage is relatively small. Tests are still needed. -- Added file: http://bugs.python.org/file21541/crlf-body-encode.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue975330 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11772] email header wrapping edge case failure
New submission from R. David Murray rdmur...@bitdance.com: I discovered the attached failure case in the process of investigating another issue. The bug (a continuation line with no leading white space) doesn't exist in 2.7, but in 2.7 the extra whitespace is not preserved (that is, the output of the new test looks just like the output of the Face2 test), which is consistent with email4's handling of header whitespace in general. -- assignee: r.david.murray components: Library (Lib) files: test_email_extra_test.patch keywords: patch messages: 133029 nosy: r.david.murray priority: normal severity: normal stage: needs patch status: open title: email header wrapping edge case failure type: behavior versions: Python 3.1, Python 3.2, Python 3.3 Added file: http://bugs.python.org/file21542/test_email_extra_test.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11772 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11771] hashlib object cannot be pickled
Antoine Pitrou pit...@free.fr added the comment: Why on Earth would you want to serialize a hashlib object? It makes as much sense as serializing, say, a JSONEncoder. -- nosy: +gregory.p.smith, pitrou ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11771 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11767] Maildir iterator leaks file descriptors by default
Changes by Antoine Pitrou pit...@free.fr: -- nosy: +r.david.murray ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11767 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue10963] subprocess can raise OSError (EPIPE) when communicating with short-lived processes
Roundup Robot devnull@devnull added the comment: New changeset c10d55c51d81 by Ross Lagerwall in branch '2.7': Issue #10963: Ensure that subprocess.communicate() never raises EPIPE. http://hg.python.org/cpython/rev/c10d55c51d81 New changeset 158495d49f58 by Ross Lagerwall in branch '3.1': Issue #10963: Ensure that subprocess.communicate() never raises EPIPE. http://hg.python.org/cpython/rev/158495d49f58 -- nosy: +python-dev ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue10963 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue10977] Concrete object C API needs abstract path for subclasses of builtin types
Benjamin Peterson benja...@python.org added the comment: I find this extremely ugly. The correct way to handle this is to use the generic methods themselves. Really, the type-specific names should only be used when you have just created the type or done PyXXX_CheckExact() yourself on it. -- nosy: +benjamin.peterson ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue10977 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue10963] subprocess can raise OSError (EPIPE) when communicating with short-lived processes
Ross Lagerwall rosslagerw...@gmail.com added the comment: Committed, thanks. -- assignee: - rosslagerwall resolution: - fixed stage: patch review - committed/rejected status: open - closed type: feature request - behavior ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue10963 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11652] urlib{, 2} returns a pair of integers as the content-length value
James Whisnant jwhisn...@gmail.com added the comment: Varnish on the sourceforge server has been upgraded and/or reconfigured (yesterday) to fix the issue that was happening with this file (and others). Just an FYI that you will no longer be able to re-create the triggering error. 'content-length': '289519', 'via': '1.1 varnish' -- nosy: +jwhisnant ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11652 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6040] bdist_msi does not deal with pre-release version
anatoly techtonik techto...@gmail.com added the comment:
Metadata can be automatically figured out using regexp matching like
^\d+(\.\d+){2,3}, but for explicit handling there should be should some
callback or msi-specific version property in metadata. In the end it is pretty
logical if binary distribution process can be configured using distribution
specific (bdist_* specific) properties.
In the meanwhile here is the workaround:
{{{
from distutils.command.bdist_msi import bdist_msi
class bdist_msi_version_hack(bdist_msi):
bdist_msi requires version to be in x.x.x format
because it is embedded into MSI
def run(self):
# strip suffix from version, i.e. from 11.0.0+r3443
saved = self.distribution.metadata.version
self.distribution.metadata.version = saved.split('+')[0]
bdist_msi.run(self)
saved_version = self.distribution.metadata.version
setup(
...
cmdclass={'bdist_msi': bdist_msi_version_hack},
)
}}}
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[issue6040] bdist_msi does not deal with pre-release version
anatoly techtonik techto...@gmail.com added the comment: Wrong code. The last line in the bdist_msi_version_hack override should be: self.distribution.metadata.version = saved -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6040 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
