Simple driver expression

Does anyone know a simple solution for this driver? I need var to be at 0 when var_001 is at 1 and I also need it to be at 0 when var_001 is at -1. So the bone goes up 1 and down -1. thanks

This probably won’t help you at all, but, sounds like a sine wave.

Actually, that did work, cheers.

Nice surprise.