X, Y, and Z must be 2D matrices. Z is a function of X and Y in this case. The following shows an example of how to use it properly
x = linspace(-1,1,10);
y = x;
[X,Y]=meshgrid(x,y);
Z = X+Y; % Z=X+Y is chosen as an example to show Z is a function of X and Y
figure,
surfnorm(X,Y,Z);
