Projective frame

In the mathematical field of projective geometry, a projective frame is an ordered collection of points in projective space which can be used as reference points to describe any other point in that space. For example:

In general, let KP denote n-dimensional projective space over an arbitrary field K. This is the projectivization of the vector space K. Then a projective frame is an (n+2)-tuple of points in general position in KP. Here general position means that no subset of n+1 of these points lies in a hyperplane (a projective subspace of dimension n−1).