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Timeline for Conditions for including cones

Current License: CC BY-SA 4.0

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May 4, 2023 at 13:34 comment added Iosif Pinelis @NathanielJohnston : Thank you for your comment.
May 3, 2023 at 20:33 comment added Nathaniel Johnston @IosifPinelis - Very nice! $N = 3$ isn't possible, so your construction is optimal. What's also kind of neat about your $N = 4$ example is that, even though they can't be rotated into the positive orthant of $\mathbb{R}^3$, they can be embedded into higher-dimensional space (e.g., by appending $0$ coordinates) and rotated into the positive orthant in that space (I think dimension $6$ suffices). Contrast that with my set of $N = 5$ vectors that can't be rotated into the positive orthant in any dimension.
May 3, 2023 at 19:34 comment added Iosif Pinelis @NathanielJohnston : It is now shown within the same framework that it is enough to have $N=4$ points, which cannot be further improved.
May 2, 2023 at 15:52 comment added Iosif Pinelis @NathanielJohnston : You wrote: "for $N$ very large". Actually, $N$ does not have to be very large using that method. It is now shown in the Added paragraph that one can take $N=14$ (or maybe even $<14$.
May 2, 2023 at 10:53 comment added Nathaniel Johnston @dzk - I'm not aware of any books other than the one that I linked.
May 1, 2023 at 18:00 comment added dzk May I ask which relevant books are there? Thank you
May 1, 2023 at 17:53 comment added Iosif Pinelis Wow, I had never heard about completely positive matrices or even suspected they were a thing! Thank you for this information.
May 1, 2023 at 17:34 history answered Nathaniel Johnston CC BY-SA 4.0