| #ifndef TEST_PACKET_OSTREAM | 
 | #define TEST_PACKET_OSTREAM | 
 |  | 
 | #include <type_traits> | 
 | #include <ostream> | 
 |  | 
 | // Include this header to be able to print Packets while debugging. | 
 |  | 
 | template <typename Packet, | 
 |           typename EnableIf = std::enable_if_t<Eigen::internal::unpacket_traits<Packet>::vectorizable> > | 
 | std::ostream& operator<<(std::ostream& os, const Packet& packet) { | 
 |   using Scalar = typename Eigen::internal::unpacket_traits<Packet>::type; | 
 |   Scalar v[Eigen::internal::unpacket_traits<Packet>::size]; | 
 |   Eigen::internal::pstoreu(v, packet); | 
 |   os << "{" << v[0]; | 
 |   for (int i = 1; i < Eigen::internal::unpacket_traits<Packet>::size; ++i) { | 
 |     os << "," << v[i]; | 
 |   } | 
 |   os << "}"; | 
 |   return os; | 
 | } | 
 |  | 
 | #endif  // TEST_PACKET_OSTREAM |