[pama]

Einsum immediately clicked with me because in my past advanced classical mechanics courses such concise contractions of multi-index creatures were really the only way to make quick sense of complicated problems without the limitations of low-dimensional array notations. Physics tensors are of course different creatures than the simpler multidimensional arrays of PyTorch and co., but the simplified einsum notation still works very well. I ended up sometimes rewriting my Einsum code to plain tensor manipulation code in order to better work with collaborators who didnt like einsum, but I still experiment in my own hacks with einsum when I need to. Occasionally I felt that it would have been nice to also have the Levi-Civita symbol available in einsum, or to be able to use complex numbers and take complex conjugates, but these are all super-specialized requests and there often is a good way around them without modifying einsum.