* max( abs(first), abs(last) )
 
                     where `first' and `last' are the coverage time
                     bounds of a type 3 segment, expressed as seconds
                     past J2000 TDB.
 
                     The resulting parameter TOL is used as a tolerance
                     for comparing the input segment descriptor time
                     bounds to the first and last epoch covered by the
                     sequence of time intervals defined by the inputs
                    