Data dimensions must agree error

This is the program I executed and it has thrown an error that data dimensions must agree.

X dimenion: 129 129 129

y dimension: 129 129 129

q dimension: 129 129 129

u0 dimension: 129 129.

Kindly help me.

% physical constants
 m =1; 
 omega =1; 
 hbar =1;

% constants defining the Gaussian IC
 a =4; 
 b =1;

 % number of grid points ( total is N+1) and the grid
 N =128;
 z=linspace(-10,10,N +1);
 [y,x,q]= meshgrid(z,z,z);
 psi = @(q)(1/sqrt(2.*b.*sqrt(pi))).*(exp(-(q - a ).^2/(2.*b^2)));
 s1=exp(-1i*q.*y);
 s2=conj(psi(x+q/2));
 s3=psi(x-q/2);
 u0=trapz(z,s1.*s2.*s3,3);
 figure(1)
 clf
 caxis([-0.1 ,0.1]) 
axis([-10 10 -10 10 -0.05 0.1])
 colorbar ;
surf(x,y,u0)

Answer 1

[Walter Roberson]

x and y coordinates for surf() must be either vectors or 2 dimensional, never 3 dimensional.

If you have 3 independent variables and one result variable, then you cannot use surf()