On Tue, Mar 17, 2020 at 9:03 PM Sebastian Berg
wrote:
> Hi all,
>
> in the spirit of trying to keep this moving, can I assume that the main
> reason for little discussion is that the actual changes proposed are
> not very far reaching as of now? Or is the reason that this is a
> fairly complex topic that you need more time to think about it?
>
Probably (a) it's a long NEP on a complex topic, (b) the past week has been
a very weird week for everyone (in the extra-news-reading-time I could
easily have re-reviewed the NEP), and (c) the amount of feedback one
expects to get on a NEP is roughly inversely proportional to the scope and
complexity of the NEP contents.
Today I re-read the parts I commented on before. This version is a big
improvement over the previous ones. Thanks in particular for adding clear
examples and the diagram, it helps a lot.
> If it is the latter, is there some way I can help with it? I tried to
> minimize how much is part of this initial NEP.
>
> If there is not much need for discussion, I would like to officially
> accept the NEP very soon, sending out an official one week notice in
> the next days.
>
I agree. I think I would like to keep the option open though to come back
to the NEP later to improve the clarity of the text about
motivation/plan/examples/scope, given that this will be the reference for a
major amount of work for a long time to come.
To summarize one more time, the main point is that:
>
This point seems fine, and I'm +1 for going ahead with the described parts
of the technical design.
Cheers,
Ralf
> type(np.dtype(np.float64))
>
> will be `np.dtype[float64]`, a subclass of dtype, so that:
>
> issubclass(np.dtype[float64], np.dtype)
>
> is true. This means that we will have one class for every current type
> number: `dtype.num`. The implementation of these subclasses will be a
> C-written (extension) MetaClass, all details of this class are supposed
> to remain experimental in flux at this time.
>
> Cheers
>
> Sebastian
>
>
> On Wed, 2020-03-11 at 17:02 -0700, Sebastian Berg wrote:
> > Hi all,
> >
> > I am pleased to propose NEP 41: First step towards a new Datatype
> > System https://numpy.org/neps/nep-0041-improved-dtype-support.html
> >
> > This NEP motivates the larger restructure of the datatype machinery
> > in
> > NumPy and defines a few fundamental design aspects. The long term
> > user
> > impact will be allowing easier and more rich featured user defined
> > datatypes.
> >
> > As this is a large restructure, the NEP represents only the first
> > steps
> > with some additional information in further NEPs being drafted [1]
> > (this may be helpful to look at depending on the level of detail you
> > are interested in).
> > The NEP itself does not propose to add significant new public API.
> > Instead it proposes to move forward with an incremental internal
> > refactor and lays the foundation for this process.
> >
> > The main user facing change at this time is that datatypes will
> > become
> > classes (e.g. ``type(np.dtype("float64"))`` will be a float64
> > specific
> > class.
> > For most users, the main impact should be many new datatypes in the
> > long run (see the user impact section). However, for those interested
> > in API design within NumPy or with respect to implementing new
> > datatypes, this and the following NEPs are important decisions in the
> > future roadmap for NumPy.
> >
> > The current full text is reproduced below, although the above link is
> > probably a better way to read it.
> >
> > Cheers
> >
> > Sebastian
> >
> >
> > [1] NEP 40 gives some background information about the current
> > systems
> > and issues with it:
> >
> https://github.com/numpy/numpy/blob/1248cf7a8765b7b53d883f9e7061173817533aac/doc/neps/nep-0040-legacy-datatype-impl.rst
> > and NEP 42 being a first draft of how the new API may look like:
> >
> >
> https://github.com/numpy/numpy/blob/f07e25cdff3967a19c4cc45c6e1a94a38f53cee3/doc/neps/nep-0042-new-dtypes.rst
> > (links to current rendered versions, check
> > https://github.com/numpy/numpy/pull/15505 and
> > https://github.com/numpy/numpy/pull/15507 for updates)
> >
> >
> > ---
> > ---
> >
> >
> > =
> > NEP 41 — First step towards a new Datatype System
> > =
> >
> > :title: Improved Datatype Support
> > :Author: Sebastian Berg
> > :Author: Stéfan van der Walt
> > :Author: Matti Picus
> > :Status: Draft
> > :Type: Standard Track
> > :Created: 2020-02-03
> >
> >
> > .. note::
> >
> > This NEP is part of a series of NEPs encompassing first
> > information
> > about the previous dtype implementation and issues with it in NEP
> > 40.
> > NEP 41 (this document) then provides an overview and generic
> > design
> > choices for the refactor.
> > Further NEPs 42 and 43 go into the technical details of the
> > datatype
> > and
