  RPYFMM is a software package for the efficient evaluation of the potential
field governed by the Rotne-Prager-Yamakawa (RPY) tensor interactions in
biomolecular hydrodynamics simulations. In our algorithm, the RPY tensor is
decomposed as a linear combination of four Laplace interactions, each of which
is evaluated using the adaptive fast multipole method (FMM) [1] where the
exponential expansions are applied to diagonalize the multipole-to-local
translation operators. RPYFMM offers a unified execution on both shared and
distributed memory computers by leveraging the DASHMM library [2, 3].
Preliminary numerical results show that the interactions for a molecular system
of 15 million particles (beads) can be computed within one second on a Cray
XC30 cluster using 12, 288 cores, while achieving approximately 54%
strong-scaling efficiency.
