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For 8 values, we first compare 4 values like this:
 
For 8 values, we first compare 4 values like this:
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[[File:Example.jpg|thumbnail]]

Revision as of 14:39, 11 September 2015

I wanted to write a short explanation about bitonic sort because it's simple as hell but no one does a good job at explaining it correctly.

You can find the video explanation here https://www.youtube.com/watch?v=GEQ8y26blEY but it's a bit tedious so to sum up the algorithm, here's what you need to know:

  • A bitonic sequence is a sequence of numbers that can be ordered as first ascending then descending (or the opposite)
    • For example: (1, 2, 3, 4) followed by (4,3,2,1) is bitonic.
  • The bitonic sort algorithm works in 2 parts:
    • (1) First, you need to transform any random sequence of numbers into a bitonic sequence
    • (2) Second, you can then sort the bitonic sequence in ascending order


And that is all there is to it! Now let's see how to execute the 2 parts of the algorithm.

Part 1: Transforming any sequence of numbers into a bitonic sequence

Part 2: Sorting the bitonic sequence

Well it's another log2(N) algorithm as in part 1. You'll need to swap numbers log2(N) times.

For 8 values, we first compare 4 values like this: