Does this code crash your matlab?

The following code segaults Matlab x64 7.14.0.739 (R2012a) on my Linux x64 3.7.9 box.

The algorithm maybe wrong, but the segfault makes me sad.

I suspect it is due to crazy values i'm passing to the draw function.

Can somebody verify?

%%Simple 2D
clear all;
clc;
pml=1;
gridSx = 100;
gridSy = 110;
Ez = zeros(gridSx,gridSy);
Hx = zeros(gridSx,gridSy);
Hy = zeros(gridSx,gridSy);
denx = ones(gridSx,1);
deny = ones(1,gridSy);
S=0.50/(1/sqrt(2) + 1/sqrt(2));
n=377;
Cav=1;
Cbv=ones(gridSx,gridSy);
Dav=1;
Dbv=ones(gridSx,gridSy);
s=1000;

%%Settings
dx=1E-3;
dy=dx;
vlight=3*10^8;
epsilon = 8.854*10^-12;
mu_naught=4*(pi)*1E-7;
sigmaE = 0.001;
dt = 0.95 / (vlight * sqrt((1.0 / (dx*dx)) + (1.0 / (dy*dy) )));
Cav=Cav*1;
Cbv=Cbv*((dt / epsilon) / (1.0 + sigmaE * dt / (2.0 * epsilon)));
Dav=Cav*1;
Dbv=Dbv*(dt / mu_naught);

%%Process
%E sourounded by H
draw =1;
for i=1:s
    %Update Ez
    for x=1:(gridSx-1)
        %left to right
        Ez(x,:)=Cav*Ez(x,:)+(S*n)*Cbv(x,:).*deny.*(( Hy(x+1,:)- Hy(x+0,:) ));
    end
    for y=1:(gridSy-1) 
        %top to bottom
        Ez(:,y)=Cav*Ez(:,y)+(S*n)*Cbv(:,y)'*denx.*(( Hx(:,y+0)- Hx(:,y+1) ));
    end
    %Update Hx
    for y=2:(gridSy-0)%top to bottom
        Hx(:,y)=Dav*Hx(:,y)+(S/n)*Cbv(:,y)'*denx.*(( Ez(:,y-1)- Ez(:,y+0) ));
    end
    %Update Hy
    for x=2:(gridSx-0)
        Hy(x,:)=Dav*Hy(x,:)+(S/n)*Cbv(x,:).*deny.*(( Ez(x+0,:)- Ez(x-1,:) ));
    end
    %%%%%%%%%%%%%%%%%%%%%%
    type = 1;
    source=0;
    ramp =120;
    switch(type)
        case 1
            source= exp(-((i-ramp)^2)/100);
        case 2
            source= sin(i*pi/ramp);
        case 3
            if (i<(ramp+1))
                source= sin((i-1)*pi/ramp);
            end
    end
    %
    Ez(gridSx/2,gridSy/2) =Ez(gridSx/2,gridSy/2)+5*source;
    %
    if (draw==1)
        surf(Ez); shading interp; lighting phong; colormap hot; axis off; zlim([-1 1]);
        set(gcf,'Color', [0 0 0], 'Number', 'off', 'Name', sprintf('FDTD, step = %i', i));
        title(sprintf('FDTD step = %i',i),'Color',[1 0 0],'FontSize', 22);
        drawnow;
    end
end
%plot(fun);

Answer 1

[Friedrich]

UPDATE

It seems to be related to the renderer. Setting the renderer to opengl makes it work fine. ZBuffer seems to have some troubles with big Z values. So add

figure('renderer','opengl')

before the for loop.

Yes crashes my 13a on Win7 too.

When uncommenting the zlim([-1 1]); part it works fine.

When using opengl neverselect and keeping that zlim part, MATLAB doesn't crash, it hangs.

Answer 2

[Walter Roberson]

Yes, it crashes R2013a on my Mac, apparently after FDTD step 33.