Hello, I have a three dimensional FDTD code. The problem I have for simulation is one dimensional. How can I use this 3D FDTD code for the 1D problem. The 1D problem is like this: in one-dimension half of the problem space is filled with a dielectric medium and the other half is free-space. A plane wave is incident on the dielectric medium from the free-space. I need to calculate the electric field at the free space-dielectric interface. Using this field and the incident field I need to calculate the reflection coefficient (in frequency domain). What modifications do I need to make to the 3D FDTD code for this 1D problem? Do I need to re-write the whole code based on 1D FDTD equations? Please advise. Thank you very much.