ABSTRACT
This chapter shows how to develop corresponding concepts and implement numerical procedures for functions of two variables defined in a physical or conceptual plane. It reviews the definition and certain properties of the Gamma function. The chapter presents the Green’s function of the fractional Laplace equation and the fractional Laplacian as a Riesz potential. The best known conventional fractional derivatives and their relation to the fractional Laplacian are also briefly reviewed. The left and right Grunwald–Letnikov fractional derivatives are defined in terms of infinite sums associated with one-sided finite-difference approximations.
