#include... Eigen::Vector3d myVector(1.0, 2.0, 3.0);
#include... Eigen::Vector3d myVector(1.0, 2.0, 3.0); double magnitude = myVector.norm();
#includeHere, the package library used is Eigen, a C++ template library for linear algebra.... Eigen::Vector3d vector1(1.0, 2.0, 3.0); Eigen::Vector3d vector2(3.0, 2.0, 1.0); Eigen::Vector3d result = vector1 - vector2;