For statement to find angle from real axis to imaginary plane?

Hello everyone,

I was wondering if it is possible to make a for statement, such that I can find the angle between my imaginary points and the real axis. If you are able to help great! Below is a copy of the code. Also, I have attached a figure of my output graph.

-Robert

CODE:

clc,clear all,close all

Tz = 0.4;

for KP = [0.9549 4 6.5463];

      t=0:0.001:5;

      num=[2*KP *Tz 2*KP]

      den=[1 2+2*KP *Tz 2*KP];

      step(num,den,t);

      hold on;
  end 

legend('k1','k2','k3');

xlabel('Time')

ylabel('y(t)')

title('Unit-Step Responses of the System')

clear all 

figure(2)

for KP=[0.9549 4 6.5463];

Tz =0.4;

num=[2*KP *Tz 2*KP];

den=[1 2+2*KP *Tz 2*KP];

rlocus(num,den);

hold on;

end

legend('k1','k2','k3');

xlabel('Real')

ylabel('Imaginary')

title('Unit-Step Responses of the System')

[KSSV]

Question not clear...angle between what and what? What variables?