Re: [Python-Dev] Yield-From Implementation Updated for Python 3

On Sun, Aug 1, 2010 at 3:54 AM, Greg Ewing wrote: > I have updated my prototype yield-from implementation > to work with Python 3.1.2. > > My work is primarily on the management and analysis of huge genomics datasets. I use Python generators extensively and intensively to perform efficient comput

Re: [Python-Dev] Issue 2986: difflib.SequenceMatcher is partly broken

On Tue, Jul 6, 2010 at 7:18 PM, Terry Reedy wrote: > [Also posted to http://bugs.python.org/issue2986 > A much faster way to find the first mismatch would be > i = 0 > while first[i] == second[i]: > i+=1 > The match ratio, based on the initial matching prefix only, is spuriously > low. >

Re: [Python-Dev] PEP 389: argparse - new command line parsing module

On Sun, Sep 27, 2009 at 8:31 PM, Fernando Perez wrote: > On Sun, 27 Sep 2009 14:57:34 -0700, Brett Cannon wrote: > > > I am going to state upfront that I am +1 for this and I encouraged > > Steven to submit this PEP on the stdlib-SIG. I still remember watching > > Steven's lightning talk at PyCon

Re: [Python-Dev] Python 3.0.1

On Tue, Jan 27, 2009 at 3:22 PM, Benjamin Peterson wrote: > > At the moment, there are 4 release blockers for 3.0.1. I'd like to see > 3.0.1 released soon (within the next month.) It would fix the hugest > mistakes in the initial release most of which have been done committed > since December. I'm

Re: [Python-Dev] Calling the GC less often when there are lots of long-lived objects

On Tue, Dec 16, 2008 at 8:00 PM, Antoine Pitrou wrote: > Christian Heimes cheimes.de> writes: > > > > Is it reasonable to implement multiple policies so the user can switch > > between them? Or is the new algorithm superior in all cases? > >

Re: [Python-Dev] C API for gc.enable() and gc.disable()

On Sat, Jun 21, 2008 at 11:20 AM, "Martin v. Löwis" <[EMAIL PROTECTED]> wrote: > In general, any solution of the "do GC less often" needs to deal with > cases where lots of garbage gets produced in a short amount of time > (e.g. in a tight loop), and which run out of memory when GC is done less >

Re: [Python-Dev] C API for gc.enable() and gc.disable()

On Sat, Jun 21, 2008 at 4:33 AM, "Martin v. Löwis" <[EMAIL PROTECTED]> wrote: > > I don't think expecting people to tweak gc parameters when they witness > > performance problems is reasonable. > > What follows from that? To me, the natural conclusion is "people who > witness performance problems

Re: [Python-Dev] C API for gc.enable() and gc.disable()

On Fri, Jun 20, 2008 at 10:25 AM, Antoine Pitrou <[EMAIL PROTECTED]> wrote: > > Kevin Jacobs bioinformed.com> gmail.com> > writes: > > > > +1 on a C API for enabling and disabling GC. I have several instances > where > I create a large number of objects

Re: [Python-Dev] C API for gc.enable() and gc.disable()

+1 on a C API for enabling and disabling GC. I have several instances where I create a large number of objects non-cyclic objects where I see huge GC overhead (30+ seconds with gc enabled, 0.15 seconds when disabled). +1000 to fixing the garbage collector to be smart enough to self-regulate itsel

Re: [Python-Dev] PEP: per user site-packages directory

On Jan 15, 2008 6:24 AM, Oleg Broytmann <[EMAIL PROTECTED]> wrote: > On Mon, Jan 14, 2008 at 11:41:47PM +, Jon Ribbens wrote: > > It makes sense, but personally I have never heard before of ~/.local. > > Whereas ~/bin is something I am quite familiar with. > > Me too. python-dev is the only

Re: [Python-Dev] PATCH: attribute lookup caching for 2.6

On Dec 6, 2007 1:35 AM, Neil Toronto <[EMAIL PROTECTED]> wrote: > So I've applied Armin's patch to 2.6 (it was nearly clean) and am > playing with it. cls.name lookups are 15-20% faster than mine, and > inst.name lookups are 5-10% faster. His is also winning on hasattr calls > (succeeding and fail

Re: [Python-Dev] PATCH: attribute lookup caching for 2.6

On Dec 5, 2007 5:50 PM, Phillip J. Eby <[EMAIL PROTECTED]> wrote: > At 10:48 PM 12/5/2007 +0100, Georg Brandl wrote: > >Neil Toronto schrieb: > > > So Jim and PJE finally convinced me to do it the right way. :) Thanks > > > guys - it turned out very nice. > > > >How does this relate to Armin Rigo'

Re: [Python-Dev] Python developers are in demand

Just to chime in from the other side of the coin. I'm actively trying to hire qualified scientific programmers with strong Python experience. Unfortunately, I've had little success finding candidates with actual Python knowledge, resorting mainly to hiring those who've seen it and can readily lea

Re: [Python-Dev] Adding concat function to itertools

On 9/22/07, Bruce Frederiksen <[EMAIL PROTECTED]> wrote: > > I've added a new function to itertools called 'concat'. This function is > much like *chain*, but takes all of the iterables as a single argument. > I've needed this once or twice, though my implementation was called 'starchain', in li

Re: [Python-Dev] make iter() return an empty iterator?

On 8/3/07, Facundo Batista <[EMAIL PROTECTED]> wrote: > > 2007/8/3, Andrew Bennetts <[EMAIL PROTECTED]>: > > > I don't really think there's much reason to make "iter()" work. As you > say, > > What bad thing could happen if we make iter() work? If nothing, we > should ask ourselves: which is the m

Re: [Python-Dev] itertools addition: getitem()

On 7/8/07, Guido van Rossum <[EMAIL PROTECTED]> wrote: Ahem. I hope you have a better use case for getitem() than that (regardless of the default issue). I find it clearer to write that as try: compid = root[ns.company_id].next() except StopIteration: compid = None else: compid = int(comp

Re: [Python-Dev] Instance variable access and descriptors

I agree with Phillip with regard to the semantics. They are semantically desirable. However, there is a patch to add a mro cache to speed up these sorts of cases on the Python tracker, originally submitted by Armin Rigo. He saw ~20% speedups, others see less. It is currently just sitting there

Re: [Python-Dev] gzip Patch

I've tested the patch and it works as advertised for me. On 4/23/07, Florian Festi <[EMAIL PROTECTED]> wrote: Hi! I posted patch 1675951 a while ago that fixes a performance problem for small reads in the gzip stdlib module. It also removes the necessity for seeking while reading gzip files (a

Re: [Python-Dev] function for counting items in a sequence

On 4/7/07, Guido van Rossum <[EMAIL PROTECTED]> wrote: On 4/7/07, Adam Olsen <[EMAIL PROTECTED]> wrote: > On 4/7/07, Steven Bethard <[EMAIL PROTECTED]> wrote: > > Here's a patch implementing collections.counts() as suggested above: > > The name doesn't make it obvious to me what's going on. May

Re: [Python-Dev] first draft of bug guidelines for www.python.org/dev/

On 7/21/06, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: Brett> Sure.  It can also wait until we begin discussing the transitionBrett> to our next bug tracker.Would be kinda nice if the new bug tracker allowed submitters to enter afollowup email address without formally logging in.  (Of cou

Re: [Python-Dev] FW: Bug? Certainly a new *behavior* from subprocess in 2.5 on Win32

That'll teach me to fire off emails while running out the door.   Thanks.-KevinOn 7/21/06, John Benediktsson < [EMAIL PROTECTED]> wrote:> The is _active check, unless it intendeds to check for either empty or > None, should probably be revised to:>> def __del__(self):> # In case the chi

Re: [Python-Dev] FW: Bug? Certainly a new *behavior* from subprocess in 2.5 on Win32

On 7/21/06, Nick Coghlan <[EMAIL PROTECTED]> wrote: Delaney, Timothy (Tim) wrote:> Looks like there's a bug in Popen.__del__ in 2.5. I'm not in a position> to have a look right now.For those not watching python-checkins, a check for "is not None" has been added before the offending line in Popen.__

Re: [Python-Dev] FW: Bug? Certainly a new *behavior* from subprocess in 2.5 on Win32

Reported to the list about a week ago, with analysis.  Didn't get a response.  Won't use sourceforge.  Sorry about the top post.-KevinOn 7/20/06, Delaney, Timothy (Tim) <[EMAIL PROTECTED]> wrote:Larry Hastings wrote: > I run the following script:> --> from subprocess import *> Popen("ls -l")> -->

[Python-Dev] Behavior change in subprocess.py

During my testing of Python 2.5b2, I've found something that may be worthy of discussion.  I suspect that recent GC and finalization changes have altered the behavior of the Popen object in subprocess.py.  I am now getting many many many finalization warnings in my code like: Exception exceptions.A

Re: [Python-Dev] Explicit Lexical Scoping (pre-PEP?)

On 7/6/06, Evan Simpson <[EMAIL PROTECTED]> wrote: Talin wrote:> I propose to create a new type of scoping rule, which I will call> "explicit" lexical scoping, that will co-exist with the current> "implicit" scoping rule that exists in Python today. I'd like to toss one more variant into the mix.  

Re: [Python-Dev] Numerical robustness, IEEE etc.

On 6/23/06, Nick Maclaren <[EMAIL PROTECTED]> wrote: [EMAIL PROTECTED] wrote:>> > >Unfortunately, that doesn't help, because it is not where the issues> > >are.  What I don't know is how much you know about numerical models, > > >IEEE 754 in particular, and C99.  You weren't active on the SC22WG14>

Re: [Python-Dev] Numerical robustness, IEEE etc.

On 6/22/06, Nick Maclaren <[EMAIL PROTECTED]> wrote: > > Not a lot.  Annex F in itself is only numerically insane.  You need to> > know the rest of the standard, including that which is documented only> > in SC22WG14 messages, to realise the full horror. [...]>Unfortunately, that doesn't help, beca

Re: [Python-Dev] Segmentation fault in collections.defaultdict

On 6/11/06, Nick Coghlan <[EMAIL PROTECTED]> wrote: Kevin Jacobs <[EMAIL PROTECTED]> wrote:> Try this at home:> import collections> d=collections.defaultdict(int)> d.iterkeys().next()  # Seg fault > d.iteritems().next() # Seg fault> d.itervalues().next() # Fine and da

[Python-Dev] Segmentation fault in collections.defaultdict

An aside before I report this bug:_I_HATE_SOURCEFORGE_.  If it doesn't bloody accept anonymous bug reports then it bloody well shouldn't let you type in a nice, detailed, well through-out report and then toss it in the toilet when you hit Submit, and also not allow one dive in after it by using the