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The World of YouTube Bubble Sort Algorithm Dancing
theodp writes In addition to The Ghost of Steve Jobs, The Codecracker, a remix of 'The Nutcracker' performed by Silicon Valley's all-girl Castilleja School during Computer Science Education Week earlier this month featured a Bubble Sort Dance. Bubble Sort dancing, it turns out, is more popular than one might imagine. Search YouTube, for example, and you'll find students from the University of Rochester to Osmania University dancing to sort algorithms. Are you a fan of Hungarian folk-dancing? Well there's a very professionally-done Bubble Sort Dance for you! Indeed, well-meaning CS teachers are pushing kids to Bubble Sort Dance to hits like Beauty and a Beat, Roar, Gentleman, Heartbeat, Under the Sea, as well as other music.
I agree on Bubb..I mean, BS. But Selection Sort is really only useful with big objects that you don't want to move much. These days everything's a Reference, so it doesn't matter so much. It makes for a really boring dance, too.
Insertion Sort is more useful in modern use cases. If something's "almost sorted" it's very quick.
Shell sort might be even better. It's practically identical to Insertion Sort except only subsets of dancers would step out at one time. And, with a good gap sequence, it gets done much quicker than either of the above.
(T>t && O(n)--) == sqrt(666)
Hang on..
Are you seriously suggesting that bubble sort is useful for N in the millions?
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Believe it or not, but bubble sort really is used in the real world, and not because of incompetence.
Now, maybe it isn't used for most cases, but it is far from being worthless. There are situations where it's really the most optimal algorithm to run, mostly where you are both space constrained (so can't afford the extra memory to allocate more than the list to be sorted), and when you want a low number of instructions to run (because there is no other algorithm which can be performed with as few instructions as you have with bubble sort, and no, abacus sort doesn't count, as you're essentially implementing a specialized piece of hardware to do the sorting for you), but won't use a large data set in the mean time (let's say, less than 100 items, if I recall correctly, but it might be something like 10 or so, which, after that point, the extra instruction overhead in the other algorithms doesn't matter). For instance, one useful place for bubble sorts is in some drivers which need to sort integers, but which don't have a lot to sort, and which using a more complex algoritm would impair their runtime speed. With the right data set, bubble sort ends up being the most optimal algorithm for them to use, ironically.
You just forget that when we say an algorithm is O(n^2) or whatever, that we're discarding insignificant terms which don't contribute to its long term growth, because most of the time, those terms don't really matter. We don't teach any algorithms in computer science classes that are worthless to know. You just need to know when it's appropriate to use what and when, and by simply discarding bubble sort, you're kind of showing that you don't really know that, and are cargo cult programming here.
It's usually mentioned in CS courses because the first stage in introducing these classes is "think about sorting some numbers - how do you go about doing it", and generally Bubble Sort is the first formalisation that falls out of that. The fact that Selection Sort is the one that you think of is neither here nor there - most students come up with something looking like bubble sort.
It entirely depends on the order of data in the database. If you know the data is already mostly sorted, then it can perform much better than other methods.
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