average method

num? average([
  1. num value(
    1. E
    )?
])

Returns the average of all the values in this iterable.

Example:

[2, 2, 4, 8].average(); // 4.
[2, 2, 4, 8].average((i) => i + 1); // 5.
[].average() // null.

Implementation

num? average([num Function(E)? value]) {
  if (isEmpty) return null;

  return sum(value) / length;
}