AbelianGrape

joined 1 year ago
[–] [email protected] 2 points 1 year ago

Only the number of shuffles is linear. Shuffling an array and marking/deleting correctly-placed elements still take linear time even with a "placement oracle." It's at best O(n^2) so the algorithm still wouldn't be a good sorting algorithm.

It's like doing selection sort, except we're selecting a random set of elements (from that poisson distribution) instead of the smallest one.

[–] [email protected] 7 points 1 year ago* (last edited 1 year ago)

I'm not sure the median is what you want. The worst case behavior is unbounded. There is no guarantee that such an algorithm ever actually terminates, and in fact (with very low probability) it may not! But that means there is no well-defined median; we can't enumerate the space.

So let's instead ask about the average, which is meaningful, as the increasingly high iteration-count datapoints are also decreasingly likely, in a way that we can compute without trying to enumerate all possible sequences of shuffles.

Consider the problem like this: at every iteration, remove the elements that are in the correct positions and continue sorting a shorter list. As long as we keep getting shuffles where nothing is in the correct position, we can go forever. Such shuffles are called derangements, and the probability of getting one is 1/e. That is, the number of derangements of n items is the nearest integer to n!/e, so the probability of a derangement would be 1/n! * [n!/e]. This number converges to 1/e incredibly quickly as n grows - unsurprisingly, the number of correct digits is on the order of the factorial of n.

We're now interested in partial derangements D_{n,k}; the number of permutations of n elements which have k fixed points. D_{n,0} is the number of derangements, as established that is [n!/e]. Suppose k isn't 0. Then we can pick k points to be correctly sorted, and multiply by the number of derangements of the others, for a total of nCk * [(n-k)!/e]. Note that [1/e] is 0, indeed, it's not possible for exactly one element to be out of place.

So what's the probability of a particular partial derangement? Well now we're asking for D_{n,k}/n!. That would be nCk/n! * [(n-k)!/e]. Let's drop the nearest integer bit and call it an approximation, then (nCk * (n-k)!)/(n! * e) = 1/(k!*e). Look familiar? That's a Poisson distribution with λ = 1!

But if we have a Poisson distribution with λ = 1, then that means that on average we expect one new sorted element per shuffle, and hence we expect to take n shuffles. I'll admit, I was not expecting that when I started working this out. I wrote a quick program to average some trials as a sanity check and it seems to hold.

[–] [email protected] 3 points 1 year ago

I'm a bit confused by your comment. They say in their post that they will reevaluate when Lemmy's mod tools improve. More granular control over federation could help too. It's a temporary measure.

It's not like they're taking extreme action because they want to cause schisms. "They will defederate with everyone" only seems to apply if every other huge instance also has high numbers of trolls. Maybe not so unlikely, but mod tools on Lemmy will hopefully improve by then. Note: you sign up for beehaw's rules when you choose to interact on beehaw, not when you sign up to beehaw. The issue they are dealing with here is that they have had to disproportionately moderate users interacting on beehaw coming from those instances.

And at the end of the day, if beehaw becomes too isolated, it takes like 5 clicks to open a different instance in my browser and sign up there instead.

[–] [email protected] 1 points 1 year ago

Lemmy specifically hasn't implemented less harsh measures yet. This is a stop-gap action to cut off a trolling problem at its source. The beehaw admins say they will reevaluate when less drastic tools are available, e.g. allow beehaw users to interact with lemmy.world but not the other way around.

I'm not sure I 100% agree, personally, but beehaw's ethos is "be(e) nice" and if trolls are trolling, it can make it very hard for some people to open up and contribute. So I see where it's coming from.

[–] [email protected] 1 points 1 year ago

Shadow of the Colossus and Undertale.

[–] [email protected] 2 points 1 year ago

Yeah, these are examples of the bad gameplay patterns I was referring to. One of them in particular (trying to be spoiler-light) provides you a ranged power... But you have to go to melee range to activate it. Whose idea was that?

[–] [email protected] 0 points 1 year ago* (last edited 1 year ago) (1 children)

I searched for it before posting the original comment and it appeared.

[–] [email protected] 1 points 1 year ago (2 children)

Casually, I enjoyed it a lot. It felt like better BOTW, with much more new stuff to explore than I expected. My only gripes where the delay on quick menus (botw did not have that, and it feels awful) and I generally think the sage mechanic leads to bad play patterns. But overall, it's amazing.

I've been involved in speedrunning both games. Versioning issues in TOTK are way worse. Movement tech in botw was a lot more interesting and varied, until windbombs were found anyway. The menu lag feels even worse while speedrunning. The stuff we've got for inside shrines is pretty cool, and there's some very cool out-of-bounds stuff found already. So it'll probably stay fresh for a while. I'm not sure if it'll hold me for as long as botw did though.

[–] [email protected] 6 points 1 year ago* (last edited 1 year ago) (5 children)

Search for [email protected] in Beehaw's search and it should come up. This initial search would cause federation.

However, if the instance you're searching for has been explicitly defederated with by Beehaw, you won't be able to see it here at all. We're federated with that instance already though, I thought, so it's strange that it wasn't showing up with other search terms.

[–] [email protected] 5 points 1 year ago

As in could instances on different forks federate with each other? Sure. We already federate with mastodon instances and with kbin and other fediverse platforms. Having two versions of Lemmy is more an issue for maintenance, as well sharing new features and fixes between the forks.

[–] [email protected] 25 points 1 year ago (3 children)

To his credit, Ohanian hasn't been involved with reddit for a while. He and u/spez sold the company years ago, then spez came back.

[–] [email protected] 4 points 1 year ago

I totally agree. Just want to point out you mean "raze." I was confused for a bit.

 

Up front: obviously, major spoilers, so if you care about spoilers for how the master sword makes its appearance in Tears of the Kingdom, do not watch!

Normally I don't post things like this on Reddit, but I figure Lemmy needs users who actually post content, so, let's do this :)

I've been working on routing and running this category for a couple of weeks now. This is maybe the 6th or 7th iteration of the route, and this run was sort of a "route test" as much as a run, so I can do even better.

Most of the TOTK speedrunning community has been laser-focused on any% since the game came out. They've done some really impressive stuff and I'm excited to see what they do. There's also some interest in All Dungeons, which I'll probably take my own stab at soon. However, there doesn't seem to be much interest yet for this category, which was a real gem in Breath of the Wild speedrunning for several years.

To avoid spoilers, I won't give the exact rules here, but I can put them in a comment or something if that seems safe.

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