Why am I getting this error : "Warning: Imaginary parts of complex X and/or Y arguments ignored " .

close all;
clc;
t = (0:pi/3:2*pi);
r = 2;
cx = r*sqrt(3)*cos(pi/2+1i*pi/3);
cy = r*sqrt(3)*sin(pi/2+1i*pi/3);

ax = cx+r*cos(t);
ay = cy+r*sin(t);

plot(ax,ay);

Warning: Imaginary parts of complex X and/or Y arguments ignored.

grid on;

for i=0:6
    cx = r*sqrt(3)*cos(pi/2+1i*pi/3);
    cy = r*sqrt(3)*sin(pi/2+1i*pi/3);
    
    ax = cx+r*cos(t);
    ay = cy+r*sin(t);
    plot(ax,ay);
    
    hold on;
    plot(-9+ax, ay-1.8);
    
    hold on;
    plot(9+ax, ay+1.8);
    
    hold on;
    plot(6-ax,ay-6.9);
    
    grid on;
    text(-0.2,0,'A');
    text(-0.2,3.5,'B');
    text(-3.2,1.75,'C');
    text(-3.2,-1.75,'D');
    text(-0.2,-3.5,'E');
    text(2.8,-1.75,'F');
    text(2.8,1.75,'G');
    text(5.8,-7,'A');
    text(5.8,-3.5,'B');
    text(2.8,-5.3,'C');
    text(2.8,-8.75,'D');
    text(5.8,-10.5,'E');
    text(8.8,-8.75,'F');
    text(8.8,-5.25,'G');
    text(8.8,1.75,'A');
    text(8.8,5.25,'B');
    text(5.8,3.45,'C');
    text(5.8,0,'D');
    text(8.8,-1.75,'E');
    text(11.8,0,'F');
    text(11.8,3.5,'G');
    text(-9.2,-1.75,'A');
    text(-9.2,1.75,'B');
    text(-12.2,0,'C');
    text(-12.2,-3,5,'D');
    text(-9.2,-5.3,'E');
    text(-6.2,-3.5,'F');
    text(-6.2,0,'G');   
end

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Answer 1

[Cris LaPierre]

Because you are trying to plot complex values on cartesian axes. You create cx and cy as complex numbers

%                       vv   imaginary
cx = r*sqrt(3)*cos(pi/2+1i*pi/3);
cy = r*sqrt(3)*sin(pi/2+1i*pi/3);
%                       ^^   imaginary

You might look into the functions real, imag, and abs depending what it is you want to view.

Answer 2

[yanqi liu]

sir，use

warning off all