Re: Precision Tail-off?

2023-02-17 Thread Stephen Tucker
As a follow-up to my previous message, I have just produced the following log on IDLE, for your information: -- >>> math.e ** (math.log (12345678900) / 3) 4.979338592181741e+16 >>> 10 ** (math.log10

Re: Precision Tail-off?

2023-02-17 Thread Stephen Tucker
Thanks, one and all, for your reponses. This is a hugely controversial claim, I know, but I would consider this behaviour to be a serious deficiency in the IEEE standard. Consider an integer N consisting of a finitely-long string of digits in base 10. Consider the infinitely-precise cube root

Re: Precision Tail-off?

2023-02-17 Thread Richard Damon
On 2/17/23 5:27 AM, Stephen Tucker wrote: Thanks, one and all, for your reponses. This is a hugely controversial claim, I know, but I would consider this behaviour to be a serious deficiency in the IEEE standard. Consider an integer N consisting of a finitely-long string of digits in base 10.

Re: Precision Tail-off?

2023-02-17 Thread Weatherby,Gerard
IEEE did not define a standard for floating point arithmetics. They designed multiple standards, including a decimal float point one. Although decimal floating point (DFP) hardware used to be manufactured, I couldn’t find any current manufacturers. There was a company that seemed to be active

RE: Precision Tail-off?

2023-02-17 Thread avi.e.gross
Stephen, What response do you expect from whatever people in the IEEE you want? The specific IEEE standards were designed and agreed upon by groups working in caveman times when the memory and CPU time were not so plentiful. The design of many types, including floating point, had to work

Re: Precision Tail-off?

2023-02-17 Thread Michael Torrie
On 2/17/23 03:27, Stephen Tucker wrote: > Thanks, one and all, for your reponses. > > This is a hugely controversial claim, I know, but I would consider this > behaviour to be a serious deficiency in the IEEE standard. No matter how you do it, there are always tradeoffs and inaccuracies moving

Re: Precision Tail-off?

2023-02-17 Thread Peter Pearson
On Fri, 17 Feb 2023 10:27:08, Stephen Tucker wrote:[Head-posting undone.] > On Thu, Feb 16, 2023 at 6:49 PM Peter Pearson > wrote: >> On Tue, 14 Feb 2023 11:17:20 +, Oscar Benjamin wrote: >> > On Tue, 14 Feb 2023 at 07:12, Stephen Tucker >> wrote: >> [snip] >> >> I have just produced the

Re: Comparing caching strategies

2023-02-17 Thread Peter J. Holzer
On 2023-02-17 00:07:12 -0500, avi.e.gr...@gmail.com wrote: > Roaring bitmaps claim to be an improvement not only over uncompressed > structures but some other compressed versions but my reading shows it > may be limited to some uses. Bitsets in general seem to be useful only > for a largely

Re: LRU cache

2023-02-17 Thread Dino
Thank you, Gerard. I really appreciate your help Dino On 2/16/2023 9:40 PM, Weatherby,Gerard wrote: I think this does the trick: https://gist.github.com/Gerardwx/c60d200b4db8e7864cb3342dd19d41c9 #!/usr/bin/env python3 import collections import random from typing import Hashable, Any,

Re: Precision Tail-off?

2023-02-17 Thread Peter J. Holzer
On 2023-02-17 10:27:08 +, Stephen Tucker wrote: > This is a hugely controversial claim, I know, but I would consider this > behaviour to be a serious deficiency in the IEEE standard. > > Consider an integer N consisting of a finitely-long string of digits in > base 10. > > Consider the

Re: Precision Tail-off?

2023-02-17 Thread Grant Edwards
On 2023-02-17, Mats Wichmann wrote: > And... this topic as a whole comes up over and over again, like > everywhere. That's an understatement. I remember it getting rehashed over and over again in various USENET groups 35 years ago when when the VAX 11/780 BSD machine on which I read news

Re: Precision Tail-off?

2023-02-17 Thread Peter J. Holzer
On 2023-02-17 08:38:58 -0700, Michael Torrie wrote: > On 2/17/23 03:27, Stephen Tucker wrote: > > Thanks, one and all, for your reponses. > > > > This is a hugely controversial claim, I know, but I would consider this > > behaviour to be a serious deficiency in the IEEE standard. > > No matter

Re: Precision Tail-off?

2023-02-17 Thread Peter J. Holzer
On 2023-02-17 14:39:42 +, Weatherby,Gerard wrote: > IEEE did not define a standard for floating point arithmetics. They > designed multiple standards, including a decimal float point one. > Although decimal floating point (DFP) hardware used to be > manufactured, I couldn’t find any current

Re: Precision Tail-off?

2023-02-17 Thread Oscar Benjamin
On Fri, 17 Feb 2023 at 10:29, Stephen Tucker wrote: > > Thanks, one and all, for your reponses. > > This is a hugely controversial claim, I know, but I would consider this > behaviour to be a serious deficiency in the IEEE standard. [snip] > > Perhaps this observation should be brought to the

Re: Precision Tail-off?

2023-02-17 Thread Grant Edwards
On 2023-02-17, Richard Damon wrote: > [...] > >> Perhaps this observation should be brought to the attention of the IEEE. I >> would like to know their response to it. > > That is why they have developed the Decimal Floating point format, to > handle people with those sorts of problems. > > They

Re: Precision Tail-off?

2023-02-17 Thread Mats Wichmann
On 2/17/23 11:42, Richard Damon wrote: On 2/17/23 5:27 AM, Stephen Tucker wrote: The key factor here is IEEE floating point is storing numbers in BINARY, not DECIMAL, so a multiply by 1000 will change the representation of the number, and thus the possible resolution errors. Store you

RE: Comparing caching strategies

2023-02-17 Thread avi.e.gross
Peter, Analogies I am sharing are mainly for me to wrap my head around an idea by seeing if it matches any existing ideas or templates and is not meant to be exact. Fair enough? But in this case, from my reading, the analogy is rather reasonable. The implementation of Roaring Bitmaps seems to

Python 3.11.2, 3.10.10

2023-02-17 Thread אורי
Hi, I was surprised that Python 3.11.2 and 3.10.10 have been released without a notice to this mailing list. What happened? Thanks, Uri. אורי u...@speedy.net On Wed, Dec 7, 2022 at 1:03 AM Łukasz Langa wrote: > Greetings! We bring you a slew of releases this fine Saint Nicholas / >

Re: Precision Tail-off?

2023-02-17 Thread Chris Angelico
On Sat, 18 Feb 2023 at 12:41, Greg Ewing via Python-list wrote: > > On 18/02/23 7:42 am, Richard Damon wrote: > > On 2/17/23 5:27 AM, Stephen Tucker wrote: > >> None of the digits in RootNZZZ's string should be different from the > >> corresponding digits in RootN. > > > > Only if the storage

Re: Precision Tail-off?

2023-02-17 Thread Greg Ewing via Python-list
On 18/02/23 7:42 am, Richard Damon wrote: On 2/17/23 5:27 AM, Stephen Tucker wrote: None of the digits in RootNZZZ's string should be different from the corresponding digits in RootN. Only if the storage format was DECIMAL. Note that using decimal wouldn't eliminate this particular problem,

Re: Precision Tail-off?

2023-02-17 Thread Michael Torrie
On 2/17/23 15:03, Grant Edwards wrote: > Every fall, the groups were again full of a new crop of people who had > just discovered all sorts of bugs in the way > implemented floating point, and pointing them to a nicely written > document that explained it never did any good. But to be fair,

Re: Precision Tail-off?

2023-02-17 Thread Oscar Benjamin
On Sat, 18 Feb 2023 at 01:47, Chris Angelico wrote: > > On Sat, 18 Feb 2023 at 12:41, Greg Ewing via Python-list > wrote: > > > > On 18/02/23 7:42 am, Richard Damon wrote: > > > On 2/17/23 5:27 AM, Stephen Tucker wrote: > > >> None of the digits in RootNZZZ's string should be different from the

Re: Precision Tail-off?

2023-02-17 Thread Thomas Passin
On 2/17/2023 5:27 AM, Stephen Tucker wrote: Thanks, one and all, for your reponses. This is a hugely controversial claim, I know, but I would consider this behaviour to be a serious deficiency in the IEEE standard. Consider an integer N consisting of a finitely-long string of digits in base