How to sort a multidimensional vector of floats?

Question

So, I have a set of points in 3D, and I would like to store them in a 3 dimensional vector. Then I need sort that vector, giving priority first to the X dimention, then Y, then

Answer 1

...giving priority first to the X dimention, then Y, then Z

Use std::sort with std::tie, something like following

#include 
#include 
//....

struct Points // Your 3D Point
{
    float x,y,z;
} ;

std::vector v; // Vector of 3D points

std::sort( v.begin(), v.end(), 
            []( const Points& lhs, const Points& rhs )
            {
                return std::tie(lhs.x,lhs.y,lhs.z) 
                     < std::tie(rhs.x,rhs.y,rhs.z)  ; 

            }
         ) ;

_DEMO