Create a Point from a C++ Vector

Question

Is there a way to create a C++ Point directly from a std::vector without first creating an Array?

More importantly, can the coordinates be output from a Point directly to a std:vector?

Answer 1

1. You can use Point's constructor accepting a dim and a a raw array, passing it your vector's data:

   std::vector<double> vec {1, 2, 3};
   Point p(3, vec.data());
   

2. This one is harder. You basically need to alias your buffer telling std::vector to use the memory that Point already allocated. You can achieve this with a custom allocator, but the amount of boilerplate grows pretty fast. See e.g. this question on StackOverflow.