Can I decrease allocations here?

New to Julia
14

Actually, here’s a version with just 2 allocations:

function locate_vector3(
    values::AbstractVector{<:Real},
    gridpoints;
    locate_below::Bool=false,
    locate_above::Bool=false,
)
    function incrementalsearch(low, value, gridpoints)
        while value >= gridpoints[low + 1]
            low += 1
        end
        return low
    end

    indices = fill(1, size(values))
    weights = fill((NaN, NaN), size(values))

    low = 1
    high = length(gridpoints) - 1

    for ix in eachindex(values)
        if values[ix] <= gridpoints[1]
            if !locate_below
                weights[ix] = (1.0, 0.0)
            end
        elseif values[ix] >= gridpoints[end]
            indices[ix:end] .= length(gridpoints) - 1

            if !locate_above
                weights[ix:end] .= Ref((0.0, 1.0))
            end

            break
        elseif low == high
            indices[ix] = high
        else
            indices[ix] = low = incrementalsearch(low, values[ix], gridpoints)
        end
    end

    for i in eachindex(weights)
        w = weights[i]
        if isnan(w[1])
            grid1 = gridpoints[indices[i]]
            grid2 = gridpoints[indices[i]+1]
            val = values[i]
            weights[i] = ((grid2 - val) / (grid2 - grid1),
                          (val - grid1) / (grid2 - grid1))
        end
    end
    return indices, weights
end

1.7.2> @btime locate_vector3($values, $gridpoints; locate_above=true);
  575.275 ns (2 allocations: 2.64 KiB)
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