On Sun, Sep 13, 2020 at 12:32:54AM -0400, Random832 wrote:
> This isn't what I was suggesting - I meant something like this:
>
> class instancemethod:
> def __init__(self, wrapped):
> self.wrapped = wrapped
> def __get__(self, obj, objtype):
> if obj is None: return self.w
On Sat, Sep 12, 2020, at 23:14, Steven D'Aprano wrote:
> We already have an instancemethod, it's just spelled differently:
>
> py> from types import MethodType
>
>
> And while it is not useful as a decorator, it is *really* useful for
> adding methods to an individual instance rather than t
Indeed the usual definition of isnan reads:
def isnan(x):
return x != x
___
Python-ideas mailing list -- python-ideas@python.org
To unsubscribe send an email to python-ideas-le...@python.org
https://mail.python.org/mailman3/lists/python-ideas.p
On Sat, Sep 12, 2020 at 07:25:30PM -0400, Eric V. Smith wrote:
> On 9/12/2020 7:13 PM, Random832 wrote:
> >On Fri, Sep 11, 2020, at 19:57, Cameron Simpson wrote:
> >>The default (an instance method) requires "self" to perform.
> >Of course, this is only the default if the method is a function objec
On Sat, Sep 12, 2020 at 02:09:11PM -1000, David Mertz wrote:
> On Sat, Sep 12, 2020, 2:02 PM Steven D'Aprano wrote:
>
> > In general though, Python doesn't support generating the full range of
> > NANs with payloads directly.
>
>
> I've researched this a little bit for discussion in a book I'm
On Sat, Sep 12, 2020 at 05:37:23PM -0700, Christopher Barker wrote:
> On Sat, Sep 12, 2020 at 5:05 PM Steven D'Aprano wrote:
> > IEEE-754 requires that float literals overflow to infinity.
>
> sure, which means that, e.g. 1e100 * 1e300 would overflow to Inf.
>
> But that doesn't say anything a
On 9/12/20 8:48 PM, Paul Bryan wrote:
> I meant to ask, why is nan not comparable? Even:
>
> >>> math.nan == math.nan
> False
It's the IEEE definition of nan, a nan will compare unequal to ALL
values, even another nan.
It is also neither greater than or less than any value.
--
Richard Damon
___
I meant to ask, why is nan not comparable? Even:
>>> math.nan == math.nan
False
___
Python-ideas mailing list -- python-ideas@python.org
To unsubscribe send an email to python-ideas-le...@python.org
https://mail.python.org/mailman3/lists/python-ideas.py
On Sun, 2020-09-13 at 10:01 +1000, Steven D'Aprano wrote:
> If you have an INF, then you can generate a NAN with `INF - INF`.
>>> math.inf - math.inf
nan
>>> (math.inf - math.inf) == math.nan
False
___
Python-ideas mailing list -- python-ideas@pytho
On Sat, Sep 12, 2020 at 5:05 PM Steven D'Aprano wrote:
> On Sat, Sep 12, 2020 at 12:56:25PM -0700, Christopher Barker wrote:
>
> > Is there any guarantee in Python or the C spec, or the IEEE spec that,
> e.g.:
> > 1e1
> > would create an Inf value, rather than an error of some sort?
>
> IEEE-
I probably should have added "user exposed" or something to my comment.
Those extra bits certainly seem to offer compiler optimization
possibilities, as apparently SpiderMonkey does with WASM.
I can easily *imagine* a library like NumPy or PyTorch deciding to expose
something useful with those 52
As per tagged nans, check for JavaScript tagged NaN optimization.
Essentially, the tag of the NaN (i.e. the mantissa) is interpreted as a
pointer. Obviously, this is a very advanced use case, probably not worth
Python guaranteeing such behavior.
Here is one article:
https://brionv.com/log/2018/05/1
On Sat, Sep 12, 2020, 2:02 PM Steven D'Aprano wrote:
> In general though, Python doesn't support generating the full range of
> NANs with payloads directly.
I've researched this a little bit for discussion in a book I'm writing, and
I have not been able to identify ANY widely used programming l
On Sat, Sep 12, 2020 at 12:56:25PM -0700, Christopher Barker wrote:
> Is there any guarantee in Python or the C spec, or the IEEE spec that, e.g.:
>
> 1e1
>
> would create an Inf value, rather than an error of some sort?
IEEE-754 requires that float literals overflow to infinity.
I don't h
On 9/12/2020 7:13 PM, Random832 wrote:
On Fri, Sep 11, 2020, at 19:57, Cameron Simpson wrote:
The default (an instance method) requires "self" to perform.
Of course, this is only the default if the method is a function object. If it
is a different callable class, the default is effectively sta
On Fri, Sep 11, 2020, at 19:57, Cameron Simpson wrote:
> The default (an instance method) requires "self" to perform.
Of course, this is only the default if the method is a function object. If it
is a different callable class, the default is effectively staticmethod.
Perhaps there should be an @
not really relevant anyway, but the issue with using a really large literal
to get Infinity is not that some possible future system could hold really
huge numbers, but whether a too-large-for-the-implimentation literal get
evaluated as Inf at all.
Is there any guarantee in Python or the C spec, or
On Sat, Sep 12, 2020 at 1:40 AM Serhiy Storchaka
wrote:
> Second, the resulting function would have monstrous interface. open()
> takes 8 arguments,
well, maybe not -- this would not need to support the entire open()
interface:
* No one is suggesting getting rid of the current load() function,
On Sat, Sep 12, 2020 at 5:29 AM Stephen J. Turnbull <
turnbull.stephen...@u.tsukuba.ac.jp> wrote:
> See Naoki Inada's post for why this might be a good idea even though
> it's a three-line function. It's not open and shut (for one thing, on
> most modern systems the system default encoding is alr
On 9/11/20 7:35 PM, Christopher Barker wrote:
-
> But the real question is why staticmethod at all?
>
> And the answer is that there is very little use for staticmethod in
> Python [...]
On 9/11/20 7:28 PM, Greg Ewing wrote:
---
On Sat, Sep 12, 2020 at 11:06:35AM -0400, Cade Brown wrote:
> If, in the future, Python used a library such as MPFR and made all floats a
> given precision (say, by giving a flag to the interpreter "python
> -prec2048"), it would never be enough to make infinity because it only has
> the limitation
On 9/12/2020 12:05 PM, Greg Ewing wrote:
> On 12/09/20 8:36 pm, Serhiy Storchaka wrote:
>> it is not hard to write your
>> own helper with interface and defaults that suit you. It will take less
>> time than writing a letter in a mailing list.
>
> Obviously what's needed is an IDE feature such th
On 12/09/20 8:36 pm, Serhiy Storchaka wrote:
it is not hard to write your
own helper with interface and defaults that suit you. It will take less
time than writing a letter in a mailing list.
Obviously what's needed is an IDE feature such that whenever
you write a 3-line function that you haven
On 2020-09-12 at 14:07:57 +1000,
Cameron Simpson wrote:
> Dan, I should preface this by saying I don't substantially disagree
> with you, I just work differently and want to show how and why.
> The beauty here is that you have the same pattern of
> classname.transcribe_value(value) to use whatev
If, in the future, Python used a library such as MPFR and made all floats a
given precision (say, by giving a flag to the interpreter "python
-prec2048"), it would never be enough to make infinity because it only has
the limitation of a 64 bit exponent.
This is just an example of course, probably
The Nomadic Coder writes:
> This came out personal frustration, as I use this 3 line function
> very, very often, and the whole community does.
I don't deny your experience, but mine differs. Most JSON I get as
single objects arrives as strings (eg as an attribute on an HTTP
response object),
Guido van Rossum writes:
> I don't actually understand why Stephen made this claim about
> arithmetic operations,
Stephen is often mistaken about computers (among many topics). That's
why he mostly posts on -ideas, and mostly throws drafts away rather
than post them. :-)
I would not claim tha
On Fri, Sep 11, 2020 at 11:19:05AM -1000, David Mertz wrote:
> On Fri, Sep 11, 2020 at 10:19 AM Guido van Rossum wrote:
>
> > While one may argue that writing `1e1000` is not an "arithmetic
> > operation", certainly it's certainly not "casting strings to floats", and
> > it's the simeplest way of
11.09.20 23:28, The Nomadic Coder пише:
> Hi All,
>
> This is the first time I'm posting to this mailing group, so forgive me if
> I'm making any mistakes.
>
> So one of the most common ways to load json, is via a file. This is used
> extensively in data science and the lines. We often write so
12.09.20 01:57, Guido van Rossum пише:
> What happened to "not every three-line function needs to be a built-in"?
> This is *literally* a three-line function. And I know the proposal is
> not to make it a builtin, but still... ISTM down here lies the path to PHP.
Oh, I am very glad that this princ
30 matches
Mail list logo
