Chapter 6

Mix.install([{:nx, "~> 0.5"}])

Section

defmodule NeuralNetwork do
  import Nx.Defn

  defn dense(input, weight, bias) do
    input
    |> Nx.dot(weight)
    |> Nx.add(bias)
  end

  defn activation(input) do
    Nx.sigmoid(input)
  end

  defn hidden(input, weight, bias) do
    input
    |> dense(weight, bias)
    |> activation()
  end

  # Same as `hidden`
  defn output(input, weight, bias) do
    input
    |> dense(weight, bias)
    |> activation()
  end

  defn predict(input, w1, b1, w2, b2) do
    input
    |> hidden(w1, b1)
    |> output(w2, b2)
  end
end

key = Nx.Random.key(42)
{w1, key} = Nx.Random.uniform(key)
{b1, key} = Nx.Random.uniform(key)
{w2, key} = Nx.Random.uniform(key)
{b2, key} = Nx.Random.uniform(key)

key
|> Nx.Random.uniform_split(shape: {})
|> NeuralNetwork.predict(w1, b2, w2, b2)