The OP din't claim to have created this (although arguably it's implied by it's posting without comment). Rather, that's just one of quite a number of such func

The OP din't claim to have created this (although arguably it's implied by it's posting without comment). Rather, that's just one of quite a number of such functions posted here before. I don't know their origin. So well done for remembering it, and reposting it on an appropriate day; or more likely someone else remembered, and this is just a cross-post of a cross-post of a blog of a re-post. But well done anyway.