Pi monte carlo

gistfile1.jl

using BenchmarkTools

function _pi(x::Vector, y::Vector)
    acc = 0
    @inbounds @simd for i ∈ eachindex(x)
        acc += (x[i]*x[i] + y[i]*y[i]) < 1.0
    end
    4acc/length(x)
end

function pi_mc(nsamples)
    _pi(rand(nsamples), rand(nsamples))
end

@btime pi_mc(10000000) # 54.796 ms (4 allocations: 152.59 MiB)