software package for FDTD simulation

 Meep is a free and open-source software package for electromagnetics
 simulation via the finite-difference time-domain (FDTD) method.
 .
 Its features include:
   * Free and open-source software under the GNU GPL.
   * Complete scriptability via Python, Scheme, or C++ APIs.
   * Simulation in 1d, 2d, 3d, and cylindrical coordinates.
   * Distributed memory parallelism on any system supporting MPI.
   * Arbitrary anisotropic electric permittivity ε and magnetic permeability μ,
     along with dispersive ε(ω) and μ(ω) including loss/gain,
     nonlinear (Kerr & Pockels) dielectric and magnetic materials,
     electric/magnetic conductivities σ, and saturable gain/absorption.
   * Perfectly-matched layer (PML) absorbing boundaries as well as
     Bloch-periodic and perfect-conductor boundary conditions.
   * Exploitation of symmetries to reduce the computation size, including
     even/odd mirror planes and 90°/180° rotations.
   * Arbitrary current sources including a guided-mode launcher.
   * Frequency-domain solver for finding the response to a
      continuous-wave (CW) source.
   * ε/μ and field import/export in the HDF5 data format.
   * GDSII file import for planar geometries.
   * Materials library containing predefined broadband, complex
     refractive indices.
   * Field analyses including Poynting flux, mode decomposition, near to far
     transformations, frequency extraction, local density of states (LDOS),
     modal volume, Maxwell stress tensor, arbitrary functions; completely
     programmable.
 .
 This package contains the software.