New function: new AcousticFieldPropagator

[bencox]

Description

We have a new approach to computing acoustic fields using the Acoustic Field Propagator, AFP (which computes many small simulations, potentially in parallel, and adds them rather than expanding the grid). If the new approach is always quicker than the old (memory-expansion) approach then we should replace the old AcousticFieldPropagator function with the new one. Otherwise, we could add a new function called, perhaps AcousticFieldPropagatorParallel, or something like that. Matlab code for this is attached, and Jiri Jaros has compiled binaries from C++ for this new approach.

• Decide whether to keep the old version of the AFP. If so, there is an updated version of the Matlab code (also attached) which corrects the phase term and includes absorption.
• Check the Matlab codes to ensure they meets the coding standard.
• The new C++ code option will need to be included. (How was that done with the original AcousticFieldPropagator?)
• A help example will need to be included that includes absorption (or just update existing example to include absorption).

old AFP updated with absorption and correceted phase.zip

AFP_new_ parallel_version.zip