compute A = 1/Z1
compute X3 = A X1
compute Y3 = A Y1
compute Z3 = 1
compute XX3 = X3^2
compute YY3 = Y3^2
compute ZZ3 = 1
compute XZ3 = 2 X3
compute YZ3 = 2 Y3
compute XY3 = XZ3 Y3