Just to clarify, saying that my friend is not a programmer was meant to set expectations, not to be disparaging. My friend write short scripts to accomplish specific tasks, but is not employed to write programs, has never studied programming or computer science, has never written a program longer than about 50 to 100 lines, has never written a program for someone else to use, and actively refuses to be called a programmer.
Neither of us consider that a problem or criticism, but simply a statement of fact. I play music, but I'm not a musician. I sing, but I'm not a singer. I dance, but I'm not a dancer. I write stuff, but I'm not a writer. I program, but I'm not a programmer. I do math, and use math, but I'm not a mathematician. On occasion I run, but I'm not a runner. Yes the exact boundaries are fuzzy, it's difficult to create clear and precise definitions, but to describe someone who cooks the occasional dinner "a chef", or even "a cook", is to lose distinctions I think are worth retaining, and to dilute the terms to the point of being effectively worthless.
Oh, and my friend doesn't use the mathematics particularly either, and refuses now to be called a mathematician.
But it's unlikely we'll reach agreement on this, so I just thought I'd make my position clear.