Is there a specific name for this normalization function?

I want to write a normalization function that will take a signed integer and normalize it to a double between -1 to +1. Is there a special name for this type of function, or is Normalize() what people normally call it?

Also, is there开发者_开发知识库 a native iPhone function that does this?

It is indeed called normalization. There's no function needed for it since all that's required is to scale it by the maximum and clip it to the range.