size(6.5cm,6.5cm); import olympiad;  pair origin, xhat, yhat, zhat; origin=(0,0); xhat=-(1,1); yhat=(1,0); zhat=(0,1);  draw(circle(origin,1)); draw(ellipse(origin,1,2/5),dashed); //major axis = 2, minor axis = 4/5  draw(origin--zhat,Arrow); label("$\hat{\mathbf{z}}=\left|0\right\rangle$",zhat,N); label("$-\hat{\mathbf{z}}=\left|1\right\rangle$",-zhat,S);  draw(origin--yhat,Arrow); label("$\hat{\mathbf{y}}$",yhat,E);  pair intersection; intersection = 2/sqrt(29)*xhat;  draw(origin--intersection,Arrow); label("$\hat{\mathbf{x}}$",intersection,SW);  pair psipoint = 0.6*expi(4*pi/13); pair psiprime = psipoint - (0,0.7);  draw(origin--psipoint); dot(psipoint); label("$\left|\psi\right\rangle$",psipoint,NE);  draw(psipoint--psiprime--origin,dotted);  path thetaArc,phiArc; thetaArc=Arc(origin,0.15,degrees(4*pi/13),90); phiArc=Arc(origin,0.1,degrees(angle(psiprime)),degrees(-3*pi/4));  draw(thetaArc); label("$\theta$",thetaArc);  draw(phiArc); label("$\phi$",phiArc,S);