Julia implementation of a phase unwrap function

unwrap.jl

function unwrap(v, inplace=false)
  # currently assuming an array
  unwrapped = inplace ? v : copy(v)
  for i in 2:length(v)
    while unwrapped[i] - unwrapped[i-1] >= pi
      unwrapped[i] -= 2pi
    end
    while unwrapped[i] - unwrapped[i-1] <= -pi
      unwrapped[i] += 2pi
    end
  end
  return unwrapped
end

unwrap!(v) = unwrap(v, true)

@test_approx_eq(unwrap([0.1, 0.2, 0.3, 0.4]), [0.1, 0.2, 0.3, 0.4])
@test_approx_eq(unwrap([0.1, 0.2 + 2pi, 0.3, 0.4]), [0.1, 0.2, 0.3, 0.4])  
@test_approx_eq(unwrap([0.1, 0.2 - 2pi, 0.3, 0.4]), [0.1, 0.2, 0.3, 0.4])
@test_approx_eq(unwrap([0.1, 0.2 - 2pi, 0.3 - 2pi, 0.4]), [0.1, 0.2, 0.3, 0.4])
@test_approx_eq(unwrap([0.1 + 2pi, 0.2, 0.3, 0.4]), [0.1 + 2pi, 0.2 + 2pi, 0.3 + 2pi, 0.4 + 2pi])
@test_approx_eq(unwrap([0.1, 0.2 + 6pi, 0.3, 0.4]), [0.1, 0.2, 0.3, 0.4])

test_v = [0.1, 0.2, 0.3 + 2pi, 0.4]
res_v = unwrap(test_v)
@test_approx_eq(test_v, [0.1, 0.2, 0.3 + 2pi, 0.4])
unwrap!(test_v)
@test_approx_eq(test_v, [0.1, 0.2, 0.3, 0.4])