How to plot below function of two variables

[the cyclist]

It's unclear to me how to handle the case when x is in [0,1] but y is not.

However, my solution (which only covers the known cases) should give you what you need.

Answer 1

[the cyclist]

x = 0 : 0.02 : 2; % 2 is not equal to infinity, but it shows the behavior.
y = 0 : 0.02 : 2;

[xx,yy] = meshgrid(x,y);

f = 3.*(xx<=1 & yy<=1) + exp(xx+yy).*(xx>1 & yy>1);

figure
h = mesh(xx,yy,f);