monte_carlo_pi.jl

julia> function monte_carlo_pi(n)
           p = plot(size=(400, 400), legend=false, xlims=(0, 1), ylims=(0, 1), aspect_ratio=:equal)

           points = Vector{Tuple{Float64, Float64}}(undef, n)
           is_inside = zeros(Bool, n)


           for i in 1:n
               x, y = rand(), rand()
               if x^2 + y^2 < 1
                   is_inside[i] = true
               end
               points[i] = (x, y)
           end

           inner_points = points[is_inside]
           outer_points = points[.!is_inside]

           scatter!(inner_points, label="Inside")
           scatter!(outer_points,  label="Outside", shape=:square)
           plot!(x -> sqrt(1 - x^2), 0, 1, label="Circle", color=:red)


           inside_count = sum(is_inside)
           π̋ = 4 * inside_count / n

           title!(L"\hat{\pi} = %$π̋")
       end
monte_carlo_pi (generic function with 1 method)

julia> monte_carlo_pi(300)

montecarlo.svg