% |% |  TWO REFLECTIONS MAKE A ROTATION% |v = e1; %/w = e2; %/I2 = v^w/norm(v^w); %/phi = pi/4;%/R = gexp(-I2*phi/2);%/x = e1+e3;%/clf;%/draw(x,'r'); GAtext(1.1*x,'x','r'); %/axis off; %/draw(I2,'y'); %/draw(v,'g'); GAtext(1.1*v,'v','g'); %/Rv = R*v; %/draw(Rv,'g'); GAtext(1.1*Rv,'w','g'); %/axis([-0.6 1 -0.6 0.7 -1 1]);% |  a vector x and the v^w- plane % |GAprompt; %/Sx = v*x/v; %/draw(Sx,'b'); GAtext(1.1*Sx,'v x v^{-1}','b'); %/DrawPolyline({x,Sx},'m'); %/axis([-0.6 1 -0.6 0.7 -1 1]);% |  first reflection, in v% |GAprompt; %/Rx = Rv*Sx/Rv; %/draw(Rx,'r'); GAtext(1.1*Rx,'(w v) x (w v)^{-1}','r'); %/DrawPolyline({Sx,Rx},'m'); %/axis([-0.6 1 -0.6 0.7 -1 1]);% |  second reflection, in v% |   n = 10; %% number of points on rotation arc %/   DR = gexp(-I2*phi/2/n); %/   y = x; %/   for i=1:n %/      yy = DR*y/DR; %/      DrawPolyline({y,yy},'k'); %/      y = yy; %/   end %/rej = (x^I2)/I2; %/ DrawPolyline({x,rej,Rx},'k'); %/DrawPolyline({0.00001*e1,rej},'k'); %/axis([-0.6 1 -0.6 0.7 -1 1]);% |  the result is a rotation in the v^w-plane,% |  over twice the angle from v to w% |GAorbiter(-360,10); %/