Fastest code C/C++ to select the median in a set of 27 floating point values

Question

This is the well know select algorithm. see http://en.wikipedia.org/wiki/Selection_algorithm.

I need it to find the median value of a set of 3x3x3 voxel values. Sinc

Answer 1

If you want to see algorithms look up the books by Donald E. Knuth.

PS. If you think you have invented something better, then you should be able to show that the complexity is similar or better to the complexity of the known algorithms. Which for variations based on bucket and radix is O(n) on the other hand quick-sort is only O(n.log(n)). A method that is 20% faster is still O(n.log(n)) until you can show the algorithm :-)