“…ASP provides a theoretical framework for deriving a complete set of basic signal processing concepts, including convolution, for novel index domains, using as starting point a chosen shift to which convolutions should be equivariant. To date the approach was used for index domains including graphs [34,44,45], powersets (set functions) [36], meet/join lattices [37,61], and a collection of more regular domains, e.g., [39,46,49].…”