clear all clc close all syms rho real positive syms phi real positive z = rho*(cos(phi)+1i*sin(phi)); p = 1+z+0.5*z^2; q = simplify(real(p*conj(p))); dPhi = 2*pi/1440; Phi = 0:dPhi:2*pi-dPhi; hf = figure; hold on; axis equal; grid on; for j=1:length(Phi) Q = subs(q,'phi',Phi(j)); RHO{j} = solve(Q-1, 'Real', true); figure(hf); for k=1:length(RHO{j}) plot(RHO{j}(k)*cos(Phi(j)),RHO{j}(k)*sin(Phi(j)),'k.'); end end