variance function

double variance(List<num> list)

Returns the variance of a list of numbers.

Example:

print(variance([1, 2, 3, 4, 5])); // prints: 2.5

Implementation

double variance(List<num> list) {
  num m = mean(list);
  return list.map((num x) => math.pow(x - m, 2)).reduce((a, b) => a + b) /
      (list.length - 1);
}