sage.tensor.modules: Add backend using NumPy ndarray

[mkoeppe]

https://numpy.org/doc/stable/reference/arrays.ndarray.html#the-n-dimensional-array-ndarray

https://numpy.org/doc/stable/user/basics.indexing.html#basics-indexing

Component: linear algebra

Issue created by migration from https://trac.sagemath.org/ticket/30308

[mkoeppe]

Description changed:

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+https://numpy.org/doc/stable/reference/arrays.ndarray.html#the-n-dimensional-array-ndarray

[mkoeppe]

comment:3

Setting new milestone based on a cursory review of ticket status, priority, and last modification date.

[mkoeppe]

Description changed:

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 https://numpy.org/doc/stable/reference/arrays.ndarray.html#the-n-dimensional-array-ndarray
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+https://numpy.org/doc/stable/user/basics.indexing.html#basics-indexing
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[Kd-Here]

Could you please explain it more what to do here?

[mkoeppe]

The idea would be to have a separate class that can be used instead of the class Components in sage.tensor.modules.comp when the user asks for it.

This would be similar to how Matrix in Sage supports multiple backends (implementations), depending on the base ring, i.e., what kinds of elements are in the matrix.