Running minima. Equivalent to R's cummin().
cummin()
cummin([5, 3, 4, 1, 2]); // [5, 3, 3, 1, 1] Copy
cummin([5, 3, 4, 1, 2]); // [5, 3, 3, 1, 1]
Running minima. Equivalent to R's
cummin().