As a sidenote, I don't write "import numpy as np" in jupyter notebooks (at least as long as I don't share them with others) for I have this line in my ipython startup file.
Yes, I'm aware that are preparing a mini-revolution in the random number generation. But I was waiting for the interface to settle down a bit prior to including it. I didn't know they were officially deprecated though, thanks for the info! Actually, I don't believe they will ever remove those legacy functions, though, as matlab is still way more popular than numpy overall.
It probably makes more sense if you think of matrices as n-dimentional arrays: sum eliminates the n-th dimention, insert and delete increase or decrease the n-th dimension size.
3245 words should be more than enough for that :) My greatest concern about the text that it would be too much of it for something called "Visual Guide", so I tried hard to keep it to bare minimum.
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