@testset "ANN" begin
    function ann(w1, w2, w3, x1)
        xx2 = w1 * x1
        x2 = log.(1.0 .+ exp.(xx2))   # soft RELU unit
        xx3 = w2 * x2
        x3 = log.(1.0 .+ exp.(xx3))   # soft RELU unit
        x4 = w3 * x3
        sum(1.0 ./ (1.0 .+ exp.(-x4)))  # sigmoid output
    end

    test_compare(ann; w1=rand(10,10), w2=rand(10,10), w3=rand(1,10), x1=rand(10))
    
    f = ann
    inputs = [:w1=>rand(10,10), :w2=>rand(10,10), :w3=>rand(1,10), :x1=>rand(10)]
end
