3D Surf plot

I am expecting to see 3D surface, but I think I have problem creating the mesh or something, would any one help wih this?

 N=100000; 
x = linspace(1e3,10e6,N) ;
y = linspace(100e-9,10e-3,N) ;
z = 5.*x + sqrt (1./(y.*x).^2 + 1000);
surf(x,y,z);

always I am getting z should be matrix not vector or scalar? if surf only deals with matrices, how can I plot z in 3D and surface shape? I already have it as a line in 3D using plot3 command.

Answer 1

[Star Strider]

You need to create the matrices with the meshgrid function:

N=1000;                                             % Reduce Number Of Points
x = linspace(1e3,10e6,N) ;
y = linspace(100e-9,10e-3,N) ;
[X,Y] = meshgrid(x,y);                              % Use ‘meshgrid’
z = @(x,y) 5.*x + sqrt (1./(y.*x).^2 + 1000);       % Convert To Anonymous Function 
meshc(x,y,z(X,Y));

I converted ‘z’ to an anonymous function for simplicity.