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0 pointschalst15y ago0 comments

But this optimisation is applied many times: it is the leaf case of such qsort algorithms. So it affects the constant scaling factor at all ns, not just for small ns.

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JoachimSchipper15y ago· 2 in thread

I thought I was being totally clear, but seeing your comment and its upvotes, apparently not. What exactly did your "but" refer to? I think we're in complete agreement...

(I was trying to say: here's an example where properly using a fast-for-few-elements "toy" algorithm can improve real-world performance on a "serious" problem like sorting a big chunk of data. So big-O is not everything.)

chalstOP15y ago

The point is that this improvement doesn't deliver a speed up that is significant only for small n, but a speed up everywhere.

I agree that fast on small n does matter, it's just that this isn't an example.

JoachimSchipper15y ago

Thanks for clarifying! (Still, you get a global speedup because the "inner" algorithm is fast for small n.)

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