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Comments
She's been feeling okay-ish so far, but still.
I think it's been long enough to say she'll be fine.
Also today's my Birthday.
Also, that's good to hear. Keep an eye out for aftereffects, but one can live give or take some wheezing.
I was feeling sick all day long, I got one of those quick COVID tests but It turned out negative. COVID or not, it hit me pretty hard.
Me: *mmmffmmphh*
Not Me 2: You were about to say "rope", weren't you.
1. It is a recent movie.
2. It is about at least one vampire. The vampire is probably named Morbius.
3. It is regarded as a bad movie.
4. It is a current meme.
5. Tommy Wiseau did not star in it.
6. There apparently isn't any part of the movie where Morbius's feet are connected to his head with a half twist to make him infinite.
The doctor says by Monday I should be fine and dandy. For the most part I feel fine, though I'm still coughing.
On other stuff, I feel like a lot of the common confusion with NP-completeness would go away if NP were called NDP or otherwise it was clear that the N means "non-deterministically", not "not".
I was off-computer for like a week, part out of convenience because I had some family business to attend to, but mostly I guess to see if I can. Not offline, though. You know, cell phones these days.
Meanwhile, I've been rather out-of-it for the past week or so.
And there's a chance what might be called as "viscous" or something is just sticky.
(I mean, I'm speaking from my practice, which is obviously not Anglophonic, but I believe the bulk of the joke holds.)
Similarly, there's the thing where "liquid" and "fluid" are used interchangeably in common parlance, disregarding that gases are fluids too.
Also using "non-Newtonian fluids" to refer to Bingham plastics (which aren't fluids).
holy crap
TIL: the proper technical term for the "phase" of substances like mayonnaise, toothpaste, sour cream, etc.
I see I missed a post: It's not hard to understand, but it requires learning a few things in the correct order that might get you lost if you just Google them up:
Note that all problems in P are also in NP, for example, the Euler path problem above is in P (if every vertex is connected to an even number of edges (and a few other gotchas don't apply) then yes, otherwise no, and you don't have to rely on luck for this to be doable in polynomial time). If instead of traversing edges once we check for traversing vertices once then what we get instead is the Hamiltonian path problem, you can still get lucky and find a path early on, and there are ways to reliably see whether there's one such path; an obvious way is to try all up to n! combinations of n vertices and you can do It much better than that, but there's no known way to always get a correct answer in polynomial time, it is thus not known to be in P.
NP-Hard: A problem that is at least as hard as all NP problems, that is, if you know an algorithm to solve it you can use that same algorithm to solve any NP problem, thus proving that it can't be any harder.
NP-Complete: A problem that is both NP and NP-Hard.
Now, the easiest way to prove that a problem A is NP-Hard is to prove that another problem B which is known to be NP-Hard can be translated** so as to become an instance of A, thus whatever it is that you can do to solve A you can also use to solve B, reducing B to A (it's unfortunate that "reducing" is what you do when you turn a probably-smaller problem into a bigger problem). I remember linking here a video constructing a boolean (3-SAT) circuit in Super Mario Bros., showing that the game is NP-Hard.
There's an entire network of NP-Complete problems with known ways to reduce them to other NP-Complete problems, if you know an algorithm for one, know there's a way (though not necessarily an obvious one) to use it to solve all the others. For this reason finding a single polynomial time algorithm for one such problem proves that all of them are in P and earns you a million bucks from the Millennium Prize. Despite so many problems known to be in P and others known to be NP-Complete, not one is known to be in both. While we're at it, not one is known to be between both either, though there's a candidate.
Now, this (and running time in general) gets talked about sloppily around the 'net (I assume it's because it's talked about by programmers who don't have to be very into the theoretical side of computer science), so some stuff may cause confusion, it did for me before I started really learning it:
* You may also hear about NP in terms of there being a certificate that can be checked in polynomial time to prove a "yes" answer, e.g. a possible path in the Euler path problem. These two definitions are equivalent, thought I can't remember why "certifiable" implies "luckable". If there's an NP problem where a certificate is something other than a solution to the problem, I've never heard of it.
** In polynomial time, although in my experience this is rarely an issue.
Man, this got much larger than I expected. I'll take this as a sign that deep inside I want to return to studying this stuff. I probably made mistakes there but it's long and it's late so I probably should wrap it up.
mfw
also, note to self, re-read Stormtroper's explanation of p = np sometime
Though, for a relevant reply, I've noticed I'm becoming interested in math again, although I'm finding it hard to dedicate time to pursuits like that these days.
Also, I wonder if it's a healthy thing for me to keep bringing Up people being wrong on the internet (more math stuff).
People wrong on math, I would guess the kind of math an average person is going to be most wrong about is statistics and probabilities, amirite?