Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
And how about for |x+y|. I'm interested because the mappings u=x+y and v=x-y form the basis of the Walsh Hadamard transform. Obviously then you can go on to do even more complicated iterated mappings based on that.
