In mathematics, the real coordinate space or real coordinate n-space, of dimension n, denoted R or , is the set of all ordered n-tuples of real numbers, that is the set of all sequences of n real numbers, also known as coordinate vectors.Special cases are called the real line R, the real coordinate plane R, and the real coordinate three-dimensional space R.With component-wise addition and scalar multiplication, it is a real vector space.
The coordinates over any basis of the elements of a real vector space form a real coordinate space of the same dimension as that of the vector space. Similarly, the Cartesian coordinates of the points of a Euclidean space of dimension n, E (Euclidean line, E; Euclidean plane, E; Euclidean three-dimensional space, E) form a real coordinate space of dimension n.