q =

    0.5000         0         0         0         0         0
         0         0         0         0         0         0
         0         0         0         0         0         0
         0         0         0    0.5000         0         0
         0         0         0         0         0         0
         0         0         0         0         0         0

T =

     0     0     1     0     0     0
     1     0     0     0     0     0
     0     1     0     0     0     0
     0     0     0     0     0     1
     0     0     0     1     0     0
     0     0     0     0     1     0

T * q * T' =

         0         0         0         0         0         0
         0    0.5000         0         0         0         0
         0         0         0         0         0         0
         0         0         0         0         0         0
         0         0         0         0    0.5000         0
         0         0         0         0         0         0