These earlier sightings allowed an exact calculation of the orbit of the new planet.

In extreme cases, the final result may be zero even though an exact calculation may be several million.

To produce an exact calculation, some 26 digits of accuracy would have been required.

Alternatively, a nomogram may be used to check an answer obtained from another exact calculation method.

The new method of cladistics has, for the first time, allowed the exact calculation of their evolutionary relationships.