How to find all intersections in a Matlab graph?

I have created three graphs: one tangent graph, one negative cotangent graph, and one circle.

Here is what I have so far:

%Functions
f1=@(theta1) tan(theta1)
f2=@(theta1) -cot(theta1)
t=linspace(0,2*pi);
x3=4*cos(t);
y3=4*sin(t);

%Plotting
g1=ezplot(f1,[-(5*pi)/2,(5*pi)/2])
hold on
g2=ezplot(f2,[-3*pi,3*pi])
hold on
plot(x3,y3)
grid on

I am supposed to find all intersections of the three graphs here, and that's where I am stuck. Thanks for any suggestions if you have any.

My output of the graph:

Answer 1

[KSSV]

USe this file exchange: https://in.mathworks.com/matlabcentral/fileexchange/22441-curve-intersections?requestedDomain=