function main()

Box_x = 3;
Scale = 0.5;
Box_y = Box_x/Scale;

Nx = 200;
Ny = Nx/Scale;

wavenumber = 10;

XX = linspace(-Box_x, Box_x, Nx);
YY = linspace(-Box_y, Box_y, Ny);
hx = XX(2) - XX(1);
hy = YY(2) - YY(1);
[X, Y] = meshgrid(XX, YY);

I = sqrt(-1);
Uinc = exp(I*wavenumber*Y);

% plot the initial planewave
figure(1); clf; hold on; axis equal; axis off; colormap copper;
Tweak=0*Uinc; Tweak(1, 1)=-2; Tweak(1, 2) = 4;
imagesc(real(Uinc)+Tweak); % a hack to have the colormap look better
iter = 1;
saveas(gcf, sprintf('Scattering_frame%d_Nx%d.eps', iter, Nx), 'psc2');