[Numpy-discussion] feedback request: proposal to add masks to the core ndarray

[Mark Wiebe]

On Thu, Jun 23, 2011 at 6:39 PM, Christopher Barker
<Chris.Barker at noaa.gov>wrote:

> Nathaniel Smith wrote:
> > IME
> > it's important for the default behavior to be to fail loudly when
> > things are wonky, not to silently patch them up, possibly
> > incorrectly!)
>
> +1 for default behavior to fail, raise errors, or return "unknown
> values" is these situations.
>
> Though that behavior should be over-ridable with a flag or addition
> functions (like nan-sum)
>

Yeah, I'm changing the description to be this way.

Robert Kern wrote:
> > How your proposal
> > improves on the status quo, i.e. numpy.ma.
>
> I've thought for years that masked arrays should be better integrated
> with numpy -- it seems there is a lot of code duplication and upkeep
> required to keep masked arrays working as much like regular arrays as
> possible. Particularly having third-party code work with them.
>
> And I'm not sure I can explain why, but I find myself hardly ever using
> masked arrays -- it just feels like added complication to use them -- I
> tend to work with floats and use NaN instead, even though it's often not
> as good an option.
>
> Gael Varoquaux wrote:
> > Right now, the numpy array can be seen as an extension of the C array,
> > basically a pointer, a data type, and a shape (and strides). This enables
> > easy sharing with libraries that have not been written with numpy in
> > mind.
>
> Isn't that what the PEP 3118 extended buffer protocol is supposed to be
> for?
>

PEP 3118 is for allowing multiple Python plugins to communicate about
regularly-structured array data without explicitly knowing about each other,
yes. It doesn't specify anything about masks, I'm thinking disallowing 3118
views from arrays with masks is the most consistent way to deal with that.

-Mark


>
> Anyway, good stuff!
>
> -Chris
>
>
>
>
>
>
> --
> Christopher Barker, Ph.D.
> Oceanographer
>
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