create_pec_plates.m

this a 3d fdtd code using matlab and it can be used as a reference for other structures. Dear sir,

disp('creating PEC plates on the material grid');

for ind = 1:number_of_bricks

    mtype = bricks(ind).material_type;
    sigma_pec = material_types(mtype).sigma_e;

    % convert coordinates to node indices on the FDTD grid
    blx = round((bricks(ind).min_x - fdtd_domain.min_x)/dx)+1; 
    bly = round((bricks(ind).min_y - fdtd_domain.min_y)/dy)+1; 
    blz = round((bricks(ind).min_z - fdtd_domain.min_z)/dz)+1; 

    bux = round((bricks(ind).max_x - fdtd_domain.min_x)/dx)+1; 
    buy = round((bricks(ind).max_y - fdtd_domain.min_y)/dy)+1; 
    buz = round((bricks(ind).max_z - fdtd_domain.min_z)/dz)+1; 

    % find the zero thickness bricks
    if (blx == bux)
        sigma_e_y(blx, bly:buy-1,blz:buz) = sigma_pec;
        sigma_e_z(blx, bly:buy,blz:buz-1) = sigma_pec;
    end
    if (bly == buy)
        sigma_e_z(blx:bux, bly, blz:buz-1) = sigma_pec;
        sigma_e_x(blx:bux-1, bly, blz:buz) = sigma_pec;
    end
    if (blz == buz)
        sigma_e_x(blx:bux-1,bly:buy, blz) = sigma_pec;
        sigma_e_y(blx:bux,bly:buy-1,blz)  = sigma_pec;
    end
end