This block sorts the input vector using the quicksort algorithm as described in http://en.wikipedia.org/wiki/Quicksort
Quicksort is the world's most widely used sorting algorithm, and perhaps even the world's most widely used algorithm of any kind.
More info on the mathematical behavior of the algorithm can be found in http://mathworld.wolfram.com/Quicksort.html
Does what it says, small, simply good!
great, very useful tool