wrong code at matlab - meshgrid and 3d plot

hi all ,

got a problem with my code and i'm using matlab.

T0=11;

x =-60:.1:60;

y=-60:.1:60;

[X,Y]=meshgrid(x,y);

S=(X)+(Y.*j);

H=(T0./(S.^2))*(exp(S./T0)+exp(-S./T0)-2);

surf (X, Y , abs(H));

the problam is that it gives me a graph that is black! no colors... and i know that the default is random colors but i get only black from some reason.

the other problem is that i suppose to write y=-100:0.1:100; and not -60:0.1:60; but it will not work if i try value 100. i have no idea how to fix it