Minimums
mins x mins[x]
Where x is a non-symbol sortable list, returns the running minimums of the prefixes.
Nulls are ignored, except that initial nulls are returned as infinity.
q)mins 2 5 7 1 3
2 2 2 1 1
q)mins "genie"
"geeee"
q)mins 0N 5 0N 1 3 / initial nulls return infinity
0W 5 5 1 1
mins is a uniform function, equivalent to &\.