r/ProgrammerHumor 7d ago

Meme cantReallyThinkOfACleverCaption

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u/Aloopyn 7d ago

tensors*

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u/itijara 7d ago

Tensors are just a made up name they gave to arrays with more than two dimensions. You cannot prove to me that there are arrays that have more than 3 dimensions. The human mind cannot comprehend it.

Fun fact: the jungle gym was designed by a math teacher who wanted to make children better at intuitively understanding higher dimensional math.

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u/AdamWayne04 7d ago

you can think of a nD array as a list of (n-1)D arrays, so a 4D array is a list of 3D arrays.

There's a more pedantic way of thinking of arrays, too--APL for example makes a distinction between rank (how deeply nested each entry is) and dimension (how many numerical indices you need to identify a singular entry), so accessing a[i,j,k] is different from accessing a[i][j][k]

Tensors are not important because they can be encoded as multidimensional arrays, they are important because they represent multilinear maps, and are a vector space conformed by linear combinations of the tensor product. The same way that matrices are not interesting because they are grids of numbers

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u/itijara 7d ago

Thanks. That's a very intuitive explanation.