MATLAB: How to draw equipotential surface

surface plot

For example, we have a function

f(x,y,z) = (x * y) * exp(-r)/r

with r = sqrt(x^2+y^2+z^2).

Then I want to draw the equipotential surface of this function,

the surface that satisfies f(x,y,z) = 1 or f(x,y,z) = 0.5… and something else.

How can I do it?

Best Answer

This post I wrote for the MATLAB Graphics blog explains the basic idea behind drawing implicit surfaces like this.

Related Solutions

MATLAB: How to draw equipotential lines on surface plot

If I understand correctly what you want to do, use the contour3 (link) function.

The code would go something like this:

X = [ ... ];
Y = [ ... ];
Z = [ ... ];
figure
surf(X, Y, Z)
hold on
contour3(X, Y, Z, [-1, 0, 1])
hold off
grid on

MATLAB: Plotting a multi-function surface

Is this what you want to do? If not, experiment with it. This should get you started.

f = @(x) 3.*((x >= 0) & (x <= 1)) + (log(1./x) + 3).*(x > 1);   % Function
x = linspace(0, 5, 25);                                         % Change upper Limit & Vector Length
[Xc,Yc,Zc] = cylinder(f(x), 25);                                % Create Cylinder With ‘f’ Describing Radius
figure(1)
surf(Xc, Yc, Zc)                                                % Plot Resulting Cylinder
grid on

Best Answer

Related Solutions

MATLAB: How to draw equipotential lines on surface plot

MATLAB: Plotting a multi-function surface

Related Question