SLA_KBJ - Select Epoch Prefix   

ACTION:

Select epoch prefix `B' or `J'.

CALL:

CALL sla_KBJ (JB, E, K, J)

GIVEN:

JB sla_DBJIN prefix status: 0=none, 1=`B', 2=`J'

E D epoch - Besselian or Julian

RETURNED:

K `B' or `J'

J I status: 0=OK

NOTE:

The routine is mainly intended for use in conjunction with the sla_DBJIN routine. If the value of JB indicates that an explicit B or J prefix was detected by sla_DBJIN, a `B' or `J' is returned to match. If JB indicates that no explicit B or J was supplied, the choice is made on the basis of the epoch itself; B is assumed for E <1984, otherwise J.