The class manifold is virtual; other manifold classes inherit from this class.
Details
A manifold object is characterised by a character variable type, which contains a description of the manifold, and a variable measure of type measure. A typical measure is the Euclidean distance.
FRK supports five manifolds; the real line (in one dimension), instantiated by using real_line(); the 2D plane, instantiated by using plane(); the 2D-sphere surface S2, instantiated by using sphere(); the R2 space-time manifold, instantiated by using STplane(), and the S2 space-time manifold, instantiated by using STsphere(). User-specific manifolds can also be specified, however helper functions that are manifold specific, such as auto_BAUs and auto_basis, only work with the pre-configured manifolds. Importantly, one can change the distance function used on the manifold to synthesise anisotropy or heterogeneity. See the vignette for one such example.