Fast Multipole Method

Introduction

The Fast Multipole Method (FMM) improves the complexity of the matrix-vector product

\[Ax = y\]

from $\mathcal{O}(N^2)$ to $\mathcal{O}(N)$, where $A$ is the interaction matrix of points that evaluates the Green's function for a Laplace, Helmholtz, or modified Helmholtz kernel.

A common application of the FMM is the Boundary Element Method (BEM). Further information concerning this topic can be found in FMM with the BEM.

Backend

ExaFMMt wraps the exafmm-t library through the Exafmmt_jll binary.

The current JLL build expects a BLAS/LAPACK backend to be loaded through Julia's BLAS stack. If your session has no backend configured, load one such as MKL before using ExaFMMt.