Tensors
from fossilesque@mander.xyz to science_memes@mander.xyz on 03 Sep 2024 18:55
https://mander.xyz/post/17588750

#science_memes

threaded - newest

theblueredditrefugee@lemmy.dbzer0.com on 03 Sep 2024 19:01 next collapse

The difference between a matrix and a 2d array of numbers is the operations that are performed

A tensor really isn’t standardized in the same way so it’s basically just an n-d array in my mind

leisesprecher@feddit.org on 03 Sep 2024 19:28 next collapse

It’s all just pointers with semantics attached.

socsa@piefed.social on 03 Sep 2024 21:02 collapse

Vectors with strides.

Hawk@lemmynsfw.com on 04 Sep 2024 11:01 next collapse

Well, it would still be a vector. So some standardisation.

ZILtoid1991@lemmy.world on 04 Sep 2024 11:30 next collapse

You can force a 2D array to be a matrix if you’re clever enough

azi@mander.xyz on 05 Sep 2024 07:52 collapse

good ol’ nominal typing

mumblerfish@lemmy.world on 03 Sep 2024 20:35 next collapse

A tensor is something that transform as a tensor. Gtfo Christoffel symbols.

vzq@lemmy.blahaj.zone on 04 Sep 2024 05:36 collapse

Duck typing ftw

marcos@lemmy.world on 03 Sep 2024 20:50 next collapse

How you describe a thing is different from what a thing is… A tensor is not a matrix.

And on mathematics, “what a thing is” is a completely useless concept… So, it makes no difference whatsoever.

affiliate@lemmy.world on 04 Sep 2024 17:00 collapse

the “categorical” way of defining tensor products is essentially “that thing that lets you turn multi-linear maps into linear maps”, and linear maps (of finite dimensional vector spaces) are basically matrices anyways. so i don’t see it as much of a stretch to say tensors are matrices.

(can you tell that i never took a physics class?)

muntedcrocodile@lemm.ee on 04 Sep 2024 00:07 next collapse

Everything’s a matrix if u fuck with it hard enough

ignotum@lemmy.world on 04 Sep 2024 06:38 collapse

Everything’s a matrix if you realize there is no spoon

UnRelatedBurner@sh.itjust.works on 04 Sep 2024 10:16 collapse

Sadly, they patched the spoon exploit.

ZILtoid1991@lemmy.world on 04 Sep 2024 11:31 collapse

You can still use movd, movq, movups, etc.

tatterdemalion@programming.dev on 04 Sep 2024 07:52 collapse

Square matrices are linear endomorphisms. They are isomorphic to (1,1) tensors but not any other rank of tensors.

affiliate@lemmy.world on 04 Sep 2024 16:46 collapse

a tensor is a multi-linear map V × … × V × V^^ × … × V^^ → F, and a multi-linear map V × … × V × V^^ × … × V^^ → F is the same as a linear map V ⊗ … ⊗ V ⊗ V^^ ⊗ … ⊗ V^^ → F. and a linear map is ““the same thing as”” a matrix. so in this way, you can associate matrices to tensors. (but the matrices are formed in the tensor space V ⊗ … ⊗ V ⊗ V^^ ⊗ … ⊗ V^^, not in the vector space V.)