### SLA_KBJ

Select Epoch Prefix

ACTION:
Select epoch prefix ‘B’ or ‘J’.
CALL:
CALL sla_KBJ (JB, E, K, J)
##### GIVEN:
 JB I sla_DBJIN prefix status: 0=none, 1=‘B’, 2=‘J’ E D epoch – Besselian or Julian

##### RETURNED:
 K C ‘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.