# How do I extract real and imaginary parts from 1000+ eigenvalues to test for stable nodes, unstable nodes, saddle, focus, etc.?

I am new to this program and have never programmed before. I am not sure how to proceed at all when it comes to extracting the real and imaginary numbers from the eigenvalues (generated from 1000 2x2 matrices) and I don't know how to test for stable/unstable nodes, stable/unstable focus, centers, and saddle points.

I have already generated the 1000 2 by 2 matrices and generated every single eigenvalue from them. I have also plotted these eigenvalues. However, I don't know if my next bunch of coding is even on the right track.

``````for(i in 1:k){
z=runif(4,min=-10,max=10)

points(Re(lambda[1]),Im(lambda[1]))
points(Re(lambda[2]),Im(lambda[2]))
points(Re(lambda[1]),Im(lambda[2]))
points(Re(lambda[2]),Im(lambda[1]))
``````

The top section is part of the code I used to generate my matrices with random numbers from -10 to 10. I tried extracting the real and imaginary numbers like this but do I need to add more to the list of points. Also, after this how would I even test for the nodes and other points.