If the sequence of meshes are decomposed independently the number, order and
potentially type of processor patches is likely to change. Thus the processor
patches and patch fields must be replaced with those of the new mesh.
Function1 is an abstract base-class of run-time selectable unary
functions which may be composed of other Function1's allowing the user
to specify complex functions of a single scalar variable, e.g. time.
The implementations need not be a simple or continuous functions;
interpolated tables and polynomials are also supported. In fact form of
mapping between a single scalar input and a single primitive type output
is supportable.
The primary application of Function1 is in time-varying boundary
conditions, it also used for other functions of time, e.g. injected mass
is spray simulations but is not limited to functions of time.
