What is the best way to store and use 3D coordinates in C++? [closed]

  3d, c++, coordinates, memory, performance

I am currently in the need to primarily store 3D vector coordinates (possible up to maximum precision in terms of decimals) in C++. This includes the use of 3 double (/ float) values for x, y and z, respectively.

I know I can use arrays, structures, or classes, but what I am aiming for is maximum speed in manipulation of the numbers (Should i use register for this?), in addition to minimal memory usage (preferably limited to the stack), and thus I am confused on choosing one.

Another aspect to consider are subroutines that manipulate these coordinates. Should I utilize normal functions, or utilize a class with methods in it?

Source: Windows Questions C++