ElinRE: https://infosec.exchange/@lcamtuf/116084014905792600
Any math-minded people here who can explain WTF these symbols mean? 😳😵💫
Mae, gae@elin well, ≩ should be pretty obvious.
a quick google finds ⋛ and ⋚ have opposite meaning; i.e. x ⋛ y is equivalent to y ⋚ x. this allows you to not specify which one is the larger one, yet still reason with inequalities (for instance, x ⋛ y implies -x ⋚ -y).
the other ones just seem like notational variants on this.
@deciMae but isn’t ≩ the same as >?
And my brain melts with ⋛… greater than, equal to, or less than… isn’t that just everything? 🤯 I would think x ⋛ y is also equivalent to y ⋛ x… but then… what is the point?
I think the only thing these symbols prove is that I’m not a mathematician 😅
@elin it is, yeah, but sometimes it is important to be explicit about it.
and yeah, that is everything, but if you say x ⋛ y you mean a particular one, without being particular about which one. like, the example they used on wiktionary is if f is differentiable and concave, if x1 ⋛ x2 then f'(x1) ⋚ f'(x2). i.e. the relative signs are opposite
so this is used to indicate *relative* signs. i.e. a ⋚ b and c ⋛ d means sign(a - b) = - sign(c - d).
so to be clear, that means x ⋛ y is equivalent to y ⋛ x in a vacuum, but if you write these two next to each other there is an implicit sharing of cases, meaning that (x ⋛ y and y ⋛ x) is equivalent to (x = y)
i do agree that it doesn't seem like it is very useful, and the notation is a bit confusing, but this is what it is defined as