MATLAB: Plot f(x,y) = (x+y+xy+1) / xy = 0

Question

 f(x,y) = (x+y+xy+1) / xy = 0

Hi, How can I plot 2D of the function above on MUPAD or Note ? It is simple 2D x, y space but I couldn't figure it out.

Thank you.

Answer 1

You can do that with the Symbolic Math Toolbox and the fcontour function, setting ‘LevelList’ to a vector of zeros:

syms x y
f(x,y) = (x+y+x*y+1) / (x*y);
figure(1)
fc = fcontour(f);
fc.LevelList = [0 0];

See the documentation on fcontour for details.