Index of smallest element (argmin)
This function finds the index and value of the smallest element of
an array of f64 values. If the input array is empty, it returns
an index of zero.
def argmin [n] (xs: []f64) : (f64, i64) =
reduce_comm (\(vx, ix) (vy, iy) ->
if vx < vy || (vx == vy && ix < iy)
then (vx, ix)
else (vy, iy))
(f64.highest, n)
(zip xs (iota n))> argmin [1, 5, -1, 3](-1.0f64, 2i64)The operator is carefully written to be commutative, specifically by picking the element with the lowest index in case of a tie, which allows slightly more efficient code generation.