Re: Python slices in Scheme

[Jay Sulzberger <jays@panix.com>]

On Mon, 19 Jun 2023, lloda <lloda@sarc.name> wrote:

> My library guile-newra (1) has quite general multidimensional array
> slicing. The indices < can be linear ranges or arbitrary integer
> arrays and they can have any rank. You can also use the indexed
> array as write target. If all the indices are linear ranges then the
> operation is done without copies. It also has placeholders, so you
> can skip axes, like : and ... in numpy. guile-newra's arrays are
> applicative, so you can do (thearray firstindex secondindex ...),
> without special brackets.

Dear lloda, I have not yet run your code, but I just now ran my eyes over

https://lloda.github.io/guile-newra/#Slicing

Heaven forwarding, I will run some of your code before the snows come.

Thank you!

oo--JS.


>
> You need wrappers to use it with Guile's native array types, so it
> may not be as convenient. Or maybe you don't need to handle
> arbitrary rank, then it might not be the best option. It's also far
> from finished, although the stuff I mentioned above does work.
>
> I didn't adopt Pythons -1 = end convention because in Guile arrays can have any
> base index, not necessarily 0 (whether that's a good idea or not).
>
> (1) https://lloda.github.io/guile-newra/#Slicing <https://lloda.github.io/guile-newra/#Slicing>
> https://github.com/lloda/guile-newra/ <https://github.com/lloda/guile-newra/>
> https://notabug.org/lloda/guile-newra <https://notabug.org/lloda/guile-newra>