Control point (mathematics)

In CAGD, based on Bezier's representation of a polynomial curve called [Bézier curve],

it has become customary the refer to the d-vectors p_i in a parametric representation
sum_i p_i phi_i of a curve or surface in d-space as control points, 

while the scalar-valued functions phi_i, defined over the relevant parameter domain, are the corresponding weight or blending functions. Some would reasonably insist that the blending functions form a nonnegative partition of unity, i.e., the phi_i are nonnegative and sum to 1.