The mean, also known as average, is the sum of all values over the number of values. This is a measure of central tendency: a method of finding a typical or central value of a set of numbers.

The simple mean uses the successive addition method internally to calculate it's result. Errors in floating-point addition are not accounted for, so if precision is required, the standard mean method should be used instead.

This runs in O(n), linear time, with respect to the length of the array.