I'd like to share this announcement blog post about the creation of a
consortium for array and dataframe API standardization here:
https://data-apis.org/blog/announcing_the_consortium/. It's still in the
beginning stages, but starting to take shape. We have participation from
one or more maintainers of most array and tensor libraries - NumPy,
TensorFlow, PyTorch, MXNet, Dask, JAX, Xarray. Stephan Hoyer, Travis
Oliphant and myself have been providing input from a NumPy perspective.
The effort is very much related to some of the interoperability work we've
been doing in NumPy (e.g. it could provide an answer to what's described in
At this point we're looking for feedback from maintainers at a high level
(see the blog post for details).
Also important: the python-record-api tooling and data in its repo has very
granular API usage data, of the kind we could really use when making
decisions that impact backwards compatibility.
There will be a NumPy Community meeting Wednesday September 16th at 1pm
Pacific Time (20:00 UTC). Everyone is invited and encouraged to
join in and edit the work-in-progress meeting topics and notes at:
I propose adding support for datetime64/timedelta64 in linspace and solicit
feedback on the feature. As is, linspace raises UFuncTypeError when
parameters start and stop are datetime64/timedelta64. The complementary
function arange supports these types. Work was started on this feature in PR
14700 <https://github.com/numpy/numpy/pull/14700> but has stalled and I
would like to complete it, but there are some issues worth getting feedback
1. Supporting datetime64/timedelta64 will require a special case code
path within linspace. The code path is selected based on the start
parameter data type.
2. The output dtype has to be explicitly set.
3. The step size resolution is determined by the lesser resolution of
start and dtype.
Issue 3 may lead to an unexpected result for an end-user. For example,
>>> import numpy as np
>>> np.linspace(np.timedelta64(0, "s"), np.timedelta64(1, "s"), 4,
array([ 0, 0, 0, 1000], dtype='timedelta64[ms]')
The existing solution in PR 14700 does not override the end-user's start
and dtype resolution. In this case, the end-user would have to set both
start and dtype to "ms" resolution to get the expected result.
>>> np.linspace(np.timedelta64(0, "ms"), np.timedelta64(1, "s"), 4,
array([ 0, 333, 666, 1000], dtype='timedelta64[ms]')
In PR 14700, there is some discussion of "NaT" handling. In my
implementation, "NaT" works the same as "NaN" and I am not aware of any
I am pleased to announce the release of SfePy 2020.3.
SfePy (simple finite elements in Python) is a software for solving systems of
coupled partial differential equations by finite element methods. It is
distributed under the new BSD license.
Home page: https://sfepy.org
Mailing list: https://mail.python.org/mm3/mailman3/lists/sfepy.python.org/
Git (source) repository, issue tracker: https://github.com/sfepy/sfepy
Highlights of this release
- new script for visualizations based on pyvista
- generalized Yeoh hyperelastic term + example
For full release notes see .
Contributors to this release in alphabetical order:
I would like to know your opinion on how to address a specific need of
the new PEP 637:
Such PEP would make a syntax like the following valid
obj[2, 4, x=23]
Which would resolve to a call in the form
type(obj).__getitem__(obj, 2, x=23)
type(obj).__getitem__(obj, (2, 4), x=23)
and similar for set and del.
After discussion, we currently have one open point we are unsure how
to address, that is what to pass when no positional index is passed,
We are unsure if we should resolve this call with None or the empty
tuple in the positional index:
type(obj).__getitem__(obj, None, x=23)
type(obj).__getitem__(obj, (), x=23)
You can see a detailed discussion in the PEP at L913
One of the commenters on python-ideas reported that using None might
introduce an issue in numpy, as None is used to create new axes, hence
the proposal for rejection of None as a solution.
However, we are unsure how strongly this would affect numpy and
similar packages, as well as what developer will find more natural to
receive in that case. We would like to hear your opinion on the topic.
Thank you for your help.
Our bi-weekly triage-focused NumPy development meeting is tomorrow
(Wednesday, September 9th) at 11 am Pacific Time (18:00 UTC).
Everyone is invited to join in and edit the work-in-progress meeting
topics and notes:
I encourage everyone to notify us of issues or PRs that you feel should
be prioritized or simply discussed briefly. Just comment on it so we
can label it, or add your PR/issue to this weeks topics for discussion.