Does sagemath support something similar to numpy's einsum for symbolic arrays?

[Anton Todorov]

Einsum: https://numpy.org/doc/stable/reference/generated/numpy.einsum.html

It is a way to define multiple operations on arrays of arbitrary shape. I've not seen anything that suggests this is implemented in sagemath, but I was hoping there might be something hidden.

What I need this for is to calculate symbolic results of array operations which are too cumbersome to represent as matrix operations.

[Matthias Koeppe]

You might be looking for https://doc.sagemath.org/html/en/reference/tensor_free_modules/sage/tensor/modules/tensor_with_indices.html

[Anton Todorov]

Looks close but not quite.

I'm interested in what's described here: https://stats.stackexchange.com/a/198395

Basically a dumb as bricks extension to matrices to higher dimensions with a contraction along selectable axes, with no notion of co and contravariance, and ability to have any number of elements in each dimension, e.g. a (8,1,512) shaped tensor (or n-way-array) should be possible.

From what I've seen of tensors with indices are forced to be n-dimensional cubes (along with having the co and contravariant limitations to contractions). 

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[Anton Todorov]

After a long search I found something that meets what I need: https://docs.sympy.org/latest/modules/tensor/array.html

It allows for tensors to be used as they are in ML and lets you use symbolic and numerical expressions with all the usual mathematical manipulations built on top.

It's not sagemath per se, but I did get it working within sagemath quite easily.