Re: [Python-Dev] Caching float(0.0)

skip> Most definitely. I just posted what I came up with in about two skip> minutes. I'll add some code to track the high water mark as well skip> and report back. Using the smallest change I could get away with, I came up with these allocation figures (same as before): -1.0: 2

Re: [Python-Dev] Created branch for PEP 302 phase 2 work (in C)

At 08:21 PM 10/2/2006 -0400, A.M. Kuchling wrote: >On Mon, Oct 02, 2006 at 11:27:07PM +0100, Paul Moore wrote: > > Yes, I'm quite surprised at how much has appeared in pkgutil. The > > "what's new" entry is very terse, and the module documentation itself > > hasn't been updated to mention the new s

Re: [Python-Dev] Caching float(0.0)

Terry> "Kristján V. Jónsson" <[EMAIL PROTECTED]> wrote: >> Anyway, Skip noted that 50% of all floats are whole numbers between >> -10 and 10 inclusive, Terry> Please, no. He said something like this about Terry> *non-floating-point applications* (evidence unspecified, that I

Re: [Python-Dev] Caching float(0.0)

Tim> This doesn't actually give us a very useful indication of potential Tim> memory savings. What I think would be more useful is tracking the Tim> maximum simultaneous count of each value i.e. what the maximum Tim> refcount would have been if they were shared. Most definitely.

Re: [Python-Dev] Created branch for PEP 302 phase 2 work (in C)

On Mon, Oct 02, 2006 at 11:27:07PM +0100, Paul Moore wrote: > Yes, I'm quite surprised at how much has appeared in pkgutil. The > "what's new" entry is very terse, and the module documentation itself > hasn't been updated to mention the new stuff. These two things are related, of course; I couldn

Re: [Python-Dev] Caching float(0.0)

"Kristján V. Jónsson" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] >Anyway, Skip noted that 50% of all floats are whole numbers between -10 >and 10 inclusive, Please, no. He said something like this about *non-floating-point applications* (evidence unspecified, that I remember)

[Python-Dev] PSF Infrastructure Committee's recommendation for a new issue tracker

On behalf of the PSF Infrastructure committee, I am happy to report that we have reached a recommendation for a new issue tracker for Python!But first, I want to extend our thanks to all who stepped forward to provide the committee with a test installation of an issue tracker to use as a basis of o

Re: [Python-Dev] Created branch for PEP 302 phase 2 work (in C)

At 03:48 PM 10/2/2006 -0700, Brett Cannon wrote: >On 10/2/06, Paul Moore <[EMAIL PROTECTED]> >wrote: >>On 10/2/06, Phillip J. Eby >><[EMAIL PROTECTED]> wrote: >>[SNIP] >> > I'm surprised, however, that you think working on this in C is going t

Re: [Python-Dev] Caching float(0.0)

[EMAIL PROTECTED] wrote: > Steve> By these statistics I think the answer to the original > question Steve> is clearly "no" in the general case. > > As someone else (Guido?) pointed out, the literal case isn't all that > interesting. I modified floatobject.c to track a few interesting > f

Re: [Python-Dev] Created branch for PEP 302 phase 2 work (in C)

On 10/2/06, Paul Moore <[EMAIL PROTECTED]> wrote: On 10/2/06, Phillip J. Eby <[EMAIL PROTECTED]> wrote:[SNIP]> I'm surprised, however, that you think working on this in C is going to be> *less* time than it would take to simply replace __import__ with a Python > function that reimplements PEP 302..

Re: [Python-Dev] Created branch for PEP 302 phase 2 work (in C)

On 10/2/06, Phillip J. Eby <[EMAIL PROTECTED]> wrote: > Just FYI, it's not possible (so far as I know) to implement phase 2 while > maintaining backward compatibility with existing 2.x code. So this work > shouldn't go back to the 2.x trunk without discussion of those issues. While that's a fair

Re: [Python-Dev] Created branch for PEP 302 phase 2 work (in C)

At 01:01 PM 10/2/2006 -0700, Brett Cannon wrote: >In the interest of time I have decided to go ahead and do the PEP 302 >phase 2 work in C. Just FYI, it's not possible (so far as I know) to implement phase 2 while maintaining backward compatibility with existing 2.x code. So this work shouldn'

[Python-Dev] Created branch for PEP 302 phase 2 work (in C)

In the interest of time I have decided to go ahead and do the PEP 302 phase 2 work in C.  I fully expect to tackle rewriting import in Python in my spare time after I finish this work since I will be much more familiar with how the whole import machinery works and it sounds like a fun challenge. Th

Re: [Python-Dev] Caching float(0.0)

[EMAIL PROTECTED] wrote:\/ > Steve> By these statistics I think the answer to the original question > Steve> is clearly "no" in the general case. > > As someone else (Guido?) pointed out, the literal case isn't all that > interesting. I modified floatobject.c to track a few interesting >

Re: [Python-Dev] Caching float(0.0)

Michael Hudson <[EMAIL PROTECTED]> wrote: > "Martin v. Löwis" <[EMAIL PROTECTED]> writes: > > Kristján V. Jónsson schrieb: > >> I can't see how this situation is any different from the re-use of > >> low ints. There is no fundamental law that says that ints below 100 > >> are more common than oth

Re: [Python-Dev] Caching float(0.0)

On Mon, Oct 02, 2006, "Martin v. L?wis" wrote: > Michael Hudson schrieb: >> >> I think most of >> the code posted so far has been constant time, at least in terms of >> instruction count, though some might indeed be fairly slow on some >> processors -- conversion from double to integer on the Power

Re: [Python-Dev] Caching float(0.0)

Michael Hudson schrieb: >> 1. it is possible to determine whether the value is "special" in >>constant time, and also fetch the singleton value in constant >>time for ints; the same isn't possible for floats. > > I don't think you mean "constant time" here do you? Right; I really wonder

Re: [Python-Dev] Caching float(0.0)

"Martin v. Löwis" <[EMAIL PROTECTED]> writes: > Kristján V. Jónsson schrieb: >> I can't see how this situation is any different from the re-use of >> low ints. There is no fundamental law that says that ints below 100 >> are more common than other, yet experience shows that this is so, >> and so

Re: [Python-Dev] Caching float(0.0)

I see, you are thinking of the general fractional case. My point was that whole numbers seem to pop up often and to reuse those is easy I did a test of tracking actual floating point numbers and the majority of heavy usage comes from integral values. It would indeed be strange if some fractional

Re: [Python-Dev] Caching float(0.0)

Kristján V. Jónsson schrieb: > I can't see how this situation is any different from the re-use of > low ints. There is no fundamental law that says that ints below 100 > are more common than other, yet experience shows that this is so, > and so they are reused. There are two important difference

Re: [Python-Dev] Caching float(0.0)

Well, Skip made the argument when analyzing the testsuite: "So for a largely non-floating point "application", a fair number of floats are allocated, a bit over 25% of them are -1.0, 0.0 or +1.0, and nearly 50% of them are whole numbers between -10.0 and 10.0, inclusive. " In C, there is no need

Re: [Python-Dev] Caching float(0.0)

Kristján V. Jónsson schrieb: > Well, a lot of extension code, like ours use PyFloat_FromDouble(foo); > This can be from vectors and stuff. Hmm. If you get a lot of 0.0 values from vectors and stuff, I would expect that memory usage is already high. In any case, a module that creates a lot of copi

Re: [Python-Dev] Caching float(0.0)

Nick Coghlan schrieb: >> Right. Although I do wonder what kind of software people write to run >> into this problem. As Guido points out, the numbers must be the result >> from some computation, or created by an extension module by different >> means. If people have many *simultaneous* copies of 0.

Re: [Python-Dev] PEP 315 - do while

Hans Polak wrote: > Hi Nick, > > Yep, PEP 315. Sorry about that. > > Now, about your suggestion > do: > > while > > else: > > > This is pythonic, but not logical. The 'do' will execute at least once, so > the else clause is not needed, nor is th

Re: [Python-Dev] PEP 355 status

On 9/30/06, Giovanni Bajo <[EMAIL PROTECTED]> wrote: > Guido van Rossum wrote: > > OK. Pronouncement: PEP 355 is dead. [...] > > It would be terrific if you gave us some clue about what is > wrong in PEP355, [...] Here are my guesses. I believe Guido rejected this PEP for a lot of reasons. By th

Re: [Python-Dev] Caching float(0.0)

On Sun, Oct 01, 2006 at 02:01:51PM -0400, Jean-Paul Calderone wrote: > Each line in an interactive session is compiled separately, like modules > are compiled separately. With the current implementation, literals in a > single compilation unit have a chance to be "cached" like this. Literals > in