[Numpy-discussion] Giving deprecation of e.g. `float(np.array([1]))` a shot (not 0-d)

2023-04-20 Thread Sebastian Berg
Hi all,

Unlike conversions of 0-d arrays via:

    float(np.array([1]))

conversions of 1-D or higher dimensional arrays with a single element
are a bit strange:

    float(np.array([1])) 

And deprecating it has come up often enough with many in favor, but
also many worried about the possible annoyance to users.
I decided to give the PR a shot, I may have misread the room on it
though:

    https://github.com/numpy/numpy/pull/10615

So if this turns out noisy (or you may simply disagree), I am happy to
revert!

There was always the worry that it might be painful for downstream. 
SciPy, pandas, matplotlib should all be fine (were fixed in the past
years).  And the fact that SciPy required much more changes than the
other gives me some hope that many libraries won't mind.

For end-users, I would lean towards taking it slow, but if you see
issues there we can also revert of course.

Cheers,

Sebastian
    


___
NumPy-Discussion mailing list -- numpy-discussion@python.org
To unsubscribe send an email to numpy-discussion-le...@python.org
https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
Member address: arch...@mail-archive.com


[Numpy-discussion] Re: Giving deprecation of e.g. `float(np.array([1]))` a shot (not 0-d)

2023-04-20 Thread Stephan Hoyer
On Thu, Apr 20, 2023 at 9:12 AM Sebastian Berg 
wrote:

> Hi all,
>
> Unlike conversions of 0-d arrays via:
>
> float(np.array([1]))
>
> conversions of 1-D or higher dimensional arrays with a single element
> are a bit strange:
>
> float(np.array([1]))
>
> And deprecating it has come up often enough with many in favor, but
> also many worried about the possible annoyance to users.
> I decided to give the PR a shot, I may have misread the room on it
> though:
>
> https://github.com/numpy/numpy/pull/10615
>
> So if this turns out noisy (or you may simply disagree), I am happy to
> revert!
>

This looks like a great clean-up to me, thanks for giving this a try!
___
NumPy-Discussion mailing list -- numpy-discussion@python.org
To unsubscribe send an email to numpy-discussion-le...@python.org
https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
Member address: arch...@mail-archive.com


[Numpy-discussion] Re: Giving deprecation of e.g. `float(np.array([1]))` a shot (not 0-d)

2023-04-20 Thread Evgeni Burovski
If symmetry w.r.t. pytorch is any guide, it was nice to have it:

In [38]: float(torch.as_tensor([2]))
Out[38]: 2.0

In [39]: float(np.asarray([2]))
Out[39]: 2.0

I guess this boils down to what is a scalar really: is it `scalar.size
== 1` or `scalar.ndim == 0` or something else.
But that's just a digression, nevermind.


On Thu, Apr 20, 2023 at 7:25 PM Stephan Hoyer  wrote:
>
>
> On Thu, Apr 20, 2023 at 9:12 AM Sebastian Berg  
> wrote:
>>
>> Hi all,
>>
>> Unlike conversions of 0-d arrays via:
>>
>> float(np.array([1]))
>>
>> conversions of 1-D or higher dimensional arrays with a single element
>> are a bit strange:
>>
>> float(np.array([1]))
>>
>> And deprecating it has come up often enough with many in favor, but
>> also many worried about the possible annoyance to users.
>> I decided to give the PR a shot, I may have misread the room on it
>> though:
>>
>> https://github.com/numpy/numpy/pull/10615
>>
>> So if this turns out noisy (or you may simply disagree), I am happy to
>> revert!
>
>
> This looks like a great clean-up to me, thanks for giving this a try!
> ___
> NumPy-Discussion mailing list -- numpy-discussion@python.org
> To unsubscribe send an email to numpy-discussion-le...@python.org
> https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
> Member address: evgeny.burovs...@gmail.com
___
NumPy-Discussion mailing list -- numpy-discussion@python.org
To unsubscribe send an email to numpy-discussion-le...@python.org
https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
Member address: arch...@mail-archive.com


[Numpy-discussion] Re: Giving deprecation of e.g. `float(np.array([1]))` a shot (not 0-d)

2023-04-20 Thread Robert Kern
On Thu, Apr 20, 2023 at 12:39 PM Evgeni Burovski 
wrote:

> If symmetry w.r.t. pytorch is any guide, it was nice to have it:
>
> In [38]: float(torch.as_tensor([2]))
> Out[38]: 2.0
>
> In [39]: float(np.asarray([2]))
> Out[39]: 2.0
>

My question would be: Did they have a positive use case for this behavior,
or were they just reflecting NumPy's behavior?

AFAICR, the main reasoning on our side was that there was an unambiguous
value that we _could_ return, so we might as well. And in our later
experience, it was more trouble than it was worth.

-- 
Robert Kern
___
NumPy-Discussion mailing list -- numpy-discussion@python.org
To unsubscribe send an email to numpy-discussion-le...@python.org
https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
Member address: arch...@mail-archive.com


[Numpy-discussion] Re: Giving deprecation of e.g. `float(np.array([1]))` a shot (not 0-d)

2023-04-20 Thread Warren Weckesser
On 4/20/23, Sebastian Berg  wrote:
> Hi all,
>
> Unlike conversions of 0-d arrays via:
>
> float(np.array([1]))
>
> conversions of 1-D or higher dimensional arrays with a single element
> are a bit strange:
>
> float(np.array([1]))
>
> And deprecating it has come up often enough with many in favor, but
> also many worried about the possible annoyance to users.
> I decided to give the PR a shot, I may have misread the room on it
> though:
>
> https://github.com/numpy/numpy/pull/10615
>
> So if this turns out noisy (or you may simply disagree), I am happy to
> revert!
>
> There was always the worry that it might be painful for downstream.
> SciPy, pandas, matplotlib should all be fine (were fixed in the past
> years).  And the fact that SciPy required much more changes than the
> other gives me some hope that many libraries won't mind.
>
> For end-users, I would lean towards taking it slow, but if you see
> issues there we can also revert of course.
>
> Cheers,
>
> Sebastian
>
>

Thanks Nico, and Sebastian, and everyone else involved in the PRs.

This also affects `np.float64`:

```
In [61]: np.__version__
Out[61]: '1.25.0.dev0+1203.g1acac891f'

In [62]: np.float64(0.0)
Out[62]: 0.0

In [63]: np.float64(np.array(0.0))
Out[63]: 0.0

In [64]: np.float64(np.array([0.0]))
:1: DeprecationWarning: Conversion of
an array with ndim > 0 to a scalar is deprecated, and will error in
future. Ensure you extract a single element from your array before
performing this operation. (Deprecated NumPy 1.25.)
  np.float64(np.array([0.0]))
Out[64]: 0.0

In [65]: np.float64(np.array([0.0, 0.0]))
Out[65]: array([0., 0.])

```

In 1.24.2, `np.float64(np.array([0.0])` returns the the scalar 0.0.

If passing arrays to `np.float64()` is intentionally supported, it
seems it would be more consistent for `np.float64(np.array([0.0]))` to
return `np.array([0.0])`.  That is how the other numpy types work
(e.g. `np.complex128`, `np.int64`, etc.). But I'm not sure if there is
a deprecation/update path that would get us there.

Warren

>
> ___
> NumPy-Discussion mailing list -- numpy-discussion@python.org
> To unsubscribe send an email to numpy-discussion-le...@python.org
> https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
> Member address: warren.weckes...@gmail.com
>
___
NumPy-Discussion mailing list -- numpy-discussion@python.org
To unsubscribe send an email to numpy-discussion-le...@python.org
https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
Member address: arch...@mail-archive.com


[Numpy-discussion] Re: Giving deprecation of e.g. `float(np.array([1]))` a shot (not 0-d)

2023-04-20 Thread Sebastian Berg
On Thu, 2023-04-20 at 13:59 -0400, Warren Weckesser wrote:
> On 4/20/23, Sebastian Berg  wrote:
> > Hi all,
> > 
> > 



> 
> In [64]: np.float64(np.array([0.0]))
> :1: DeprecationWarning: Conversion of
> an array with ndim > 0 to a scalar is deprecated, and will error in
> future. Ensure you extract a single element from your array before
> performing this operation. (Deprecated NumPy 1.25.)
>   np.float64(np.array([0.0]))
> Out[64]: 0.0
> 
> In [65]: np.float64(np.array([0.0, 0.0]))
> Out[65]: array([0., 0.])
> 

Hmmmpf, that would be a good follow-up to fix.  In theory a
FutureWarning I guess (returning the array), but in practice, I think
we should just give the correct array result.

(I don't love returning arrays from scalar constructors, but that is
another thing and not for now.)

- Sebsatian


> ```
> 
> In 1.24.2, `np.float64(np.array([0.0])` returns the the scalar 0.0.
> 
> If passing arrays to `np.float64()` is intentionally supported, it
> seems it would be more consistent for `np.float64(np.array([0.0]))`
> to
> return `np.array([0.0])`.  That is how the other numpy types work
> (e.g. `np.complex128`, `np.int64`, etc.). But I'm not sure if there
> is
> a deprecation/update path that would get us there.
> 
> Warren
> 
> > 
> > ___
> > NumPy-Discussion mailing list -- numpy-discussion@python.org
> > To unsubscribe send an email to numpy-discussion-le...@python.org
> > https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
> > Member address: warren.weckes...@gmail.com
> > 
> ___
> NumPy-Discussion mailing list -- numpy-discussion@python.org
> To unsubscribe send an email to numpy-discussion-le...@python.org
> https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
> Member address: sebast...@sipsolutions.net
> 


___
NumPy-Discussion mailing list -- numpy-discussion@python.org
To unsubscribe send an email to numpy-discussion-le...@python.org
https://mail.python.org/mailman3/lists/numpy-discussion.python.org/
Member address: arch...@mail-archive.com