  In his article "Powerlist: A Structure for Parallel Recursion" Jayadev Misra
wrote:
  "Many data parallel algorithms Fast Fourier Transform, Batcher's sorting
schemes and prefix sum -exhibit recursive structure. We propose a data
structure, powerlist, that permits succinct descriptions of such algorithms,
highlighting the roles of both parallelism and recursion. Simple algebraic
properties of this data structure can be exploited to derive properties of
these algorithms and establish equivalence of different algorithms that solve
the same problem."
  The quote above illustrates a widely shared assumption about recursion
implementations: either they are done in purely structural terms or they cannot
be done at all.
  Multi-dimensional interpolation on a grid is one of hosts of semi-recursive
schemes that, while often referred to as recursive and routinely described in
vaguely recursive terms, cannot be implemented as a recursion in their
structural entirety.
  This article describes a computer-implemented scheme for isolating the
recursive core of interpolation on a multi-grid, an arrangement that both stems
from and provides a structural framework to a number of multi-dimensional
interpolation optimization techniques that, once implemented, provide gains in
multi-dimensional interpolation speed that, compared to some known benchmarks,
measure in multiple orders of magnitude.
  Categories and Subject Descriptors: Multi-dimensional Programming; Concurrent
Programming; Recursion
  General terms: Parallel Processing, Prioritized Processing, Interpolation,
Recursion, Multi-Cube
