Characterising the Accuracy of Multivariable Refinable Functions via the Symbol Function

Suppose that f(x) = (f 1(x),...,f r (x))T, xR d is a vector-valued function satisfying the refinement equation f(x) = c f(2x) with finite set of Z d and some rr matricex c . The requirements for f to have accuracy p are given in terms of the symbol function m().