A lot of the times equations are meant to be general and can apply to a vast number of scenerios. For example x̄ (x-bar) is used in statistics to represent the

A lot of the times equations are meant to be general and can apply to a vast number of scenerios. For example x̄ (x-bar) is used in statistics to represent the sample mean of a distribution. It doesn't matter what your distribution is, you'd likely call it x̄. Whenever you see an equation mentioning "n", this will very often be the number of items in a set/list/array, not matter what that set is counting. Usually these equations are very general, and they don't care what "n" actually is, and this way it's easy to see where you should plug that number into. If you look at the equation for x̄ (averaging) then you'll see "n" in there, and you already know what it's for, and it's incredibly concise. If you're familiar with them they actually are named relatively well, and generally they're references that you then implement, they aren't meant to be the implementation themselves.