average method

  1. @useResult
double average(
  1. Select<E, num> select
)

Computes the average of all values. Values are created from this iterable's elements using select.

Returns double.nan if empty, or if select returns double.nan.

Example

final list = [('a', 1), ('b', 3), ('c', 5)];
list.average((e) => e.$2); // 3

Implementation details

Computing values is assumed to be cheap. Hence, values are recomputed each time rather than cached.

Implementation

@useResult double average(Select<E, num> select) => sum(select) / length;