minBy<T, R extends Comparable?> function

R? minBy<T, R extends Comparable?>(Iterable<T> iterable, R accessor(T))

Returns the minimum of all values yielded by the accessor function applied to each element in the iterable.

The minimum is determined based on the natural ordering of the values, as defined by the Comparable interface.

This function ignores elements that yield values that do not satisfy any of the following conditions:

1. The value is not null.
2. The value is not a special case like double.nan, which does not satisfy self-equality according to Object.==.

Useful for filtering and ignoring missing data in datasets.

If the iterable is empty or contains no elements that yield valid values, this function returns null.

Implementation

R? minBy<T, R extends Comparable?>(
    Iterable<T> iterable, R Function(T) accessor) {
  R? min;
  for (final element in iterable) {
    final value = accessor(element);
    if (value == null || value != value) continue;
    if (min == null || min.compareTo(value) > 0) min = value;
  }
  return min;
}