How to plot a 3D graph?

Hi, I'm new to matlab.

I'm trying to plot the 3D graph of this equation

for (-1 <= x <= 1), (-1 <= y <= 1.5), and (1 <= z <= 6) but I get errors:

Error using surf (line 71)
X, Y, Z, and C cannot be complex.

Error in heart (line 8)
surf(X,Y,Z);

Here is my code:

x = linspace(-1,1,20);  
y = linspace(-1,1.5,30);  

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

Z = 5 - sqrt(1 - X.^2 - (Y - abs(X)).^2).*cos(30.*(1 - X.^2 - (Y - abs(X)).^2));

surf(X,Y,Z);
zlim([1 6]);
xlim([-1 1]);
ylim([-1 1.5]);

Please help me fix this code, thank you.

Answer 1

[John D'Errico]

This is a perfect problem for a tool like ezsurf.

Z = @(X,Y) 5 - sqrt(1 - X.^2 - (Y - abs(X)).^2).*cos(30.*(1 - X.^2 - (Y - abs(X)).^2));
H = ezsurf(Z,[-1,1,-1,1.5],200);
view(-11,81)
shading interp

As you can see, the surface is a fairly complicated one. But it may be most apprpriate to plot this on the 14th of February.

Answer 2

[KSSV]

Z matrix is complex number. Try plotting real, imag or abs.

surf(X,Y,real(Z))   % real value 
surf(X,Y,imag(Z))   % imaginary value 
surf(X,Y,abs(Z))   % absolute value