How can I plot both a surface and line on the same plot image?

I'll start by saying this is motivated by my interest in complex numbers and analysis. This is something I feel I could do by hand, but as an engineer, it would be handy to know the tools MATLAB can offer to carry out my question.

I am looking for the following:

• 1 plot
• 2 Dimensional function (f = 2*x^2+2*x+2)
• 3 Dimensional surface to plot the complex plane. I intend to use the following video as far as how I imagine plotting the C plane in MATLAB.

Any guidance or direction would be much appreciated. Thank you!

PS: I had to put the version for clarity, but it is implied that the answer doesn't have to be possible in the version I have downloaded.

Answer 1

[Anshika Chaurasia]

Hi Richard,

It is my understanding that you want to have a 2-D line and surface plot of f = 2*x^2+2*x+2 in one plot.

You could try following code:

a = -2:0.1:2;
b = -2:0.1:2;
[A,B] = meshgrid(a,b);
Y = 2*(A+1i*B).^2 + 2*(A+1i*B) + 2;
surf(a,b,abs(Y));
hold on;
plot3(a,b*0,2*a.^2+2*a+2,'Color','red','LineWidth',5);
hold off; 

Refer to the documentation of plot3, surf and hold for better information on plotting of a surface and line plots in the same figure.