An
convex combination of a
sequence of
vectors
v1,
v2, ...,
vn is given by
c1v1 + c2v2 + ... + cnvn
where
c1,
c2, ...,
cn are
real numbers with the restriction that
c1 +
c2 + ... +
cn = 1 and
c1 > 0,
c2 > 0, ... ,
cn > 0.
For example, a convex combination of a set of points in 3-space is always some point in the convex hull of those points.