[r-t] Delta-based transposition representation

[Alan Burlison]

On 10/06/2016 09:43, Richard Smith wrote:

> Picking up on a point Don didn't mention, this isn't true. Certainly if
> it does not sum to zero then the change is invalid.  But you're arguing
> the converse, that if the detals sum to zero the change is valid.
> That's not true: invalid changes can have deltas that sum to zero too.
> Consider +1 +1 -1 -1.

Yes, it's necessary but not sufficient - kind of like a parity check ;-)

-- 
Alan Burlison
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