| 51 | }; |
| 52 | |
| 53 | struct log : public detail::stateless { |
| 54 | template <typename T> |
| 55 | static T forward(T v) { |
| 56 | return std::log(v); |
| 57 | } |
| 58 | template <typename T> |
| 59 | static T inverse(T v) { |
| 60 | return std::exp(v); |
| 61 | } |
| 62 | }; |
| 63 | |
| 64 | struct sqrt : public detail::stateless { |
| 65 | template <typename T> |