Best uniform approximation by π-superharmonic functions
Juha Heinonen, D. Zwick Β· Numerical Functional Analysis and Optimization Β· 1992
Let π be a sheaf of continuous real-valued functions on a domain . If π satisfies the axioms for a nonlinear potential theory, then we call the elements of π(U) for U βΞ© openπ-harmonic on U.We define the class π(U) of π-superharmonic functions on Uand characterize best uniform approximations to continuous functions by elements of π(U) β© C([Ubar]).