Abstract
The aim of this paper is to describe a Matlab toolbox, called mu-diff, which is designed for spectrally solving two-dimensional complex multiple scattering by a large collection of circular cylinders. The formulation is based on the Fourier series expansions of the four basic integral operators arising in scattering problems. Based on these expressions, a spectrally accurate finite-dimensional solution of multiple scattering problems can be simply obtained for complex media even when many scatterers are considered as well as large frequencies. The efficient solution of the final linear system to solve makes use of preconditioned Krylov subspace solvers for block Toeplitz matrices.