Standard solvers for the variable coefficient Helmholtz equation in two spatial dimensions have running times which grow quadratically with the wavenumber k This package contains a solver whose complexity is quasilinear in the wavenumber k, but which only applies the case of a radially symmetric scattering potential.
JamesCBremerJr/HelmRad
Fast algorithm for the solution of the variable coefficient Helmholtz equation in the radially symmetric case
Fortran