Hello My previous questions were based on the assumption that either my calculations were wrong or that I had misunderstood something.
However, the discrepancies are simply a result of round-off (I think). eg... the T matrix, when restored from Platon's EVs using Vect*Val*inverse(Vect), is: 1e-3 4.35389 -0.00488 0.00000 4.35611 0.00000 3.00000 The stated matrix is: 1e-3 4.36 0.00 0.00 4.36 0.00 3.00 The difference between the corresponding eigenvectors is large. Adam -------------------- T11 T12 T13 T22 T23 T33 (if the formatting becomes corrupted) --------------------