Mailman 3 February 2023 - NumPy-Discussion

next NumPy triage meeting - now starting at 5 pm UTC
by Inessa Pawson 17 Sep '23

17 Sep '23

The next NumPy triage meeting will be held this Wednesday, January 11th at 5 pm UTC. (Please note the new time!) This is a meeting where we synchronously triage prioritized PRs and issues. Join us via Zoom: https://numfocus-org.zoom.us/j/82096749952?pwd=MW9oUmtKQ1c3a2gydGk1RTdYUUVX… Everyone is welcome to attend and contribute to a conversation. Please notify us of issues or PRs that you’d like to have reviewed by adding a GitHub link to them in the meeting agenda: https://hackmd.io/68i_JvOYQfy9ERiHgXMPvg. -- Cheers, Inessa Inessa Pawson Contributor Experience Lead | NumPy https://numpy.org/ GitHub: inessapawson

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next NumPy community meeting
by Inessa Pawson 10 Sep '23

10 Sep '23

The next NumPy community meeting will be held this Wednesday, August 17th at 18:00 (6 pm) UTC. Join us via Zoom: https://us06web.zoom.us/j/83278611437?pwd=ekhoLzlHRjdWc0NOY2FQM0NPemdkZz09 Everyone is welcome and encouraged to attend. To add to the meeting agenda the topics you’d like to discuss, follow the link: https://hackmd.io/76o-IxCjQX2mOXO_wwkcpg?both For the notes from the previous meeting, visit: https://github.com/numpy/archive/blob/main/community_meetings/community-202… Cheers, Inessa Inessa Pawson Contributor Experience Lead | NumPy https://numpy.org/ Twitter: @inessapawson

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reminder: put an upper bound on setuptools if you use numpy.distutils!
by Ralf Gommers 31 Aug '23

31 Aug '23

Hi all, After setuptools 65.0 was released a few days ago, all users of numpy.distutils had their builds broken. This is already fixed in setuptools 65.0.2 because the breakage was particularly bad. However, the next breakage may not be fixed anymore (and more breakages *are* expected). So this is a good time to remind you all that you should put an upper bound on the setuptools version you allow in the releases of your package - to the last version that is known to work with your package. Our official stance here is that setuptools versions >=60 are not supported - see the "deprecating numpy.distutils" thread: https://mail.python.org/archives/list/numpy-discussion@python.org/message/P…. Newer versions may work for you, depending on what features you use. They don't for NumPy and for SciPy; both projects pin to 59.X to avoid problems. For the recent issue with setuptools 65.0.0, see https://github.com/numpy/numpy/issues/22135. We have also made the warnings about this topic in our docs more explicit, see https://github.com/numpy/numpy/pull/22154. Cheers, Ralf

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Adding bit_count ufunc
by Doug Turnbull 13 Aug '23

13 Aug '23

👋Long time numpy user, and big fan of all your work TL; DR - there's a `bit_count` method on numpy scalars, and Python ints, I'm advocating for a `ufunc` `bit_count` as has been implemented in this PR: https://github.com/numpy/numpy/pull/21429 A number of people have requested this as a numpy feature and there's a lot of great discussion at this issue https://github.com/numpy/numpy/issues/16325 A bit count comes up in certain similarity situations (like hamming distance). This involves an xor with numpy arrays and a bit count, where the bit count is currently the bottleneck by a few orders of magnitude in my local benchmarking. Currently there's a number of not particularly fast, workarounds for doing this with numpy arrays, like the bit-twiddling solutions here https://stackoverflow.com/a/68943135/8123 https://stackoverflow.com/a/109025/8123 So I'd love to be able to continue the work of bit_count -> numpy array ufunc to get performance gains at the array level 🙏

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mixed mode arithmetic
by Neal Becker 11 Jul '23

11 Jul '23

I've been browsing the numpy source. I'm wondering about mixed-mode arithmetic on arrays. I believe the way numpy handles this is that it never does mixed arithmetic, but instead converts arrays to a common type. Arguably, that might be efficient for a mix of say, double and float. Maybe not. But for a mix of complex and a scalar type (say, CDouble * Double), it's clearly suboptimal in efficiency. So, do I understand this correctly? If so, is that something we should improve?

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next NumPy Newcomers' Hour - 12 pm UTC
by Inessa Pawson 11 Jun '23

11 Jun '23

Our next Newcomers' Hour will be held tomorrow, December 1st, at 12 pm UTC. Stop by to ask questions or just to say hi. To add to the meeting agenda the topics you’d like to discuss, follow the link: https://hackmd.io/3f3otyyuTte3FU9y3QzsLg?both Join the meeting via Zoom: https://us06web.zoom.us/j/82563808729?pwd=ZFU3Z2dMcXBGb05YemRsaGE1OW5nQT09 -- Cheers, Inessa Inessa Pawson Contributor Experience Lead | NumPy https://numpy.org/ GitHub: inessapawson

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Representation of NumPy scalars
by Sebastian Berg 09 Jun '23

09 Jun '23

TL;DR: NumPy scalars representation is e.g. `34.3` instead of `float32(34.3)`. So the representation is missing the type information. What are your thoughts on changing that? Hi all, I am thinking about the next steps for NEP 50 (The NEP wants to fix the NumPy promotion rules, especially with respect to scalars): https://numpy.org/neps/nep-0050-scalar-promotion.html In relation to that, there was one point that Stéfan brought up previously. The NumPy scalars (representation) currently print as numbers: >>> np.float32(34.3) 34.3 >>> np.uint8(5) 5 That can already be confusing now. However, it gets more problematic if NEP 50 is introduced since the behavior between a Python `34.3` and `np.float32(34.3)` would differ more than it does now (please refer to the NEP). The change would be that we should print as: float64(34.3) (or similar?) This Email is mainly to ask for any feedback or concern on such a change. I suspect we may have to write a very brief NEP about it. If there is little concern, maybe we could move forward such a change promptly. Otherwise it could be moved forward together with NEP 50 and take effect in a "major" release [1]. Cheers, Sebastian [1] Note that for me, even a major release would hopefully not affect the majority of users or be very disruptive.

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next NumPy Newcomers' Hour - 8 pm UTC
by Inessa Pawson 28 May '23

28 May '23

Our next Newcomers' Hour will be held this Thursday, December 15th at 8 pm UTC. Stop by to ask questions or just to say hi. To add to the meeting agenda the topics you’d like to discuss, follow the link: https://hackmd.io/3f3otyyuTte3FU9y3QzsLg?both Join the meeting via Zoom: https://us06web.zoom.us/j/82563808729?pwd=ZFU3Z2dMcXBGb05YemRsaGE1OW5nQT09 -- Cheers, Inessa Inessa Pawson Contributor Experience Lead | NumPy https://numpy.org/ GitHub: inessapawson

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1D ndarray to java double[]
by Bill Ross 20 Mar '23

20 Mar '23

How best to write a 1D ndarray as a block of doubles, for reading in java as double[] or a stream of double? Maybe the performance of simple looping over doubles in python.write() and java.read() is fine, but maybe there are representational diffs? Maybe there's a better solution for the use case? Use case: I get the ndarray from keras, and it represents a 2D distance matrix. I want to find the top-50 matches for each item, per row and column. I'm looking at moving the top-50 task to java for its superior parallel threading. (Java doesn't fork processes with a copy of the array, which is ~5% of memory; rather one gets 1 process with e.g. 1475% CPU.) Thanks, Bill Ross -- Phobrain.com

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Documentation team meeting - Monday 27 February at 12 PM UTC (noon)
by Mukulika Pahari 26 Feb '23

26 Feb '23

Hi all! Our next Documentation Team meeting will happen on *Monday, February 27* at ***12PM UTC***. We now alternate the meeting times to be a bit more inclusive. This means that we'll have a meeting at 12pm UTC every 28 days, and a meeting at 4pm UTC every 28 days. All are welcome - you don't need to already be a contributor to join. If you have questions or are curious about what we're doing, we'll be happy to meet you! If you wish to join on Zoom, use this (updated) link: https://numfocus-org.zoom.us/j/85016474448?pwd=TWEvaWJ1SklyVEpwNXUrcHV1YmFJQ... Here's the permanent hackmd document with the meeting notes (still being updated): https://hackmd.io/oB_boakvRqKR-_2jRV-Qjg Hope to see you around! * You can also visit https://scientific-python.org/calendars to add the NumPy community calendar as an .ics file to your preferred calendar manager. * Best wishes, Mukulika

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