Comparison of Cartesian Treecodes

In molecular simulations it is sometimes necessary to compute the electric potential at M targets due to a disjoint set of N charged source particles. Direct summation is prohibitively expensive when M and N are large. We provide Fortran 90 code for two complementary treecode methods which reduce the cost. The standard particle-cluster treecode partitions the sources into an octree and applies a far-field approximation, while a recently developed cluster-particle treecode instead partitions the targets into an octree and applies a near-field approximation. Particle-cluster is faster when N >> M, and cluster-particle is faster when M >> N.

Reference: Boateng, H. A. and Krasny, R., J. Comput. Chem, 34(25), 2013, 2159–2167

This material is based upon work supported by the National Science Foundation under NSF Grants DMS-0854870 and DMS-0915057. Any opinions, findings, and conclusions or recommendations expressed in this material do not necessarily reflect the views of the NSF.