Function patan

include/Eigen/src/Core/GenericPacketMath.h:1064–1067

/** \internal \returns the arc tangent of \a a (coeff-wise) */
template <typename Packet>
EIGEN_DECLARE_FUNCTION_ALLOWING_MULTIPLE_DEFINITIONS Packet patan(const Packet& a) {
  EIGEN_USING_STD(atan);
  return atan(a);
}

/** \internal \returns the hyperbolic tan of \a a (coeff-wise) */
template <typename Packet>