data structures - What are some interesting/practical uses for arrays with three or more dimensions? -

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when using arrays use 1 or 2 dimensional array -- 3 or more. i'm kind of curious, interesting/practical uses arrays 3 or more dimensions? have ever used array 4 or more dimensions? had professor in college use 6 dimensional array in program demonstrated in class...ever had more this?

in scientific programming can quite common. start calling these higher dimensional arrays tensors. scalars 0-dimensional tensors, vectors 1-dimensional tensors, matrices 2-dimensional tensors, , after call them d-dimensional tensors (d=3,4,5,6). dot products called contractions on indices.

where used? use them in of physics simulations. instance, 1 method simulating electrons on lattice (regular array of sites) uses tensor different set of indices each connection neighboring site. in 2d square lattice (think sites in center of each space on chess board), means each tensor has 4 indices, 1 each neighboring site, 4-dimensional tensor.


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