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Probably this is just a lapsus lingue, but what you are saying makes no sense.

Vectors are a special case of matrices, which are a special case of tensors (finally, scalars, which is just a fancy name for plain numbers, are a special case of vectors). Although there are many mathematical representation of all these objects (geometrical, functional, etc.), they can be written as multidimensional arrays (after selecting for a base).

Thus, scalars are 1x1 matrices, and a vector of size n is actually a nx1 matrix. Although a common high-school notation of a vector is x = (1, 2, 3), a vector is actually

  x = [ 1
        2
        3 ]
Tensors are the extension of matrices to further dimensions.


Right. And how would you characterize the 4-dimensional extension, in terms of the first three?

Or do you simply draw the line at two dimensions, figuring that's as much as anyone will ever need?


What are the two dimensions of which you speak here? The 'row' and 'column' dimensions of a matrix? If so, that's exactly what tensors do: A matrix is a 2-tensor (better, a (1, 1)-tensor, but let's not get into that). If you want an m-dimensional generalisation, just use an m-tensor.




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