When should we use Radix sort?

Question

It seems Radix sort has a very good average case performance, i.e. O(kN): http://en.wikipedia.org/wiki/Radix_sort

Yet it seems like most people are still using

Answer 1

One example would be when you are sorting a very large set or array of integers. A radix sort and any other types distribution sorts are extremely fast since data elements are mainly being enqueued into an array of queues(max 10 queues for an LSD radix sort) and remapped to a different index location of the same input data to be sorted. There are no nested loops so the algorithm tends to behave more linearly as the number of data input integers to be sorted becomes significantly larger. Unlike other sorting methods, like the extremely inefficient bubbleSort method, the radix sort does not implement comparison operations to sort. Its just a simple process of remapping integers to different index positions until the input is finally sorted. If you would like to test out an LSD radix sort for yourself, I have written one out and stored on github which can be easily tested on an online js ide such as eloquent javascript's coding sandbox. Feel free to play around with it and watch how it behaves with differing numbers of n. I've tested with up to 900,000 unsorted integers with a runtime < 300ms. Here is the link if you wish to play around with it.

https://gist.github.com/StBean/4af58d09021899f14dfa585df6c86df6