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DOUBLE PRECISION FUNCTION sla_EPCO (K0, K, E)
*+
* - - - - -
* E P C O
* - - - - -
*
* Convert an epoch into the appropriate form - 'B' or 'J'
*
* Given:
* K0 char form of result: 'B'=Besselian, 'J'=Julian
* K char form of given epoch: 'B' or 'J'
* E dp epoch
*
* Called: sla_EPB, sla_EPJ2D, sla_EPJ, sla_EPB2D
*
* Notes:
*
* 1) The result is always either equal to or very close to
* the given epoch E. The routine is required only in
* applications where punctilious treatment of heterogeneous
* mixtures of star positions is necessary.
*
* 2) K0 and K are not validated. They are interpreted as follows:
*
* o If K0 and K are the same the result is E.
* o If K0 is 'B' or 'b' and K isn't, the conversion is J to B.
* o In all other cases, the conversion is B to J.
*
* Note that K0 and K won't match if their cases differ.
*
* P.T.Wallace Starlink 5 September 1993
*
* Copyright (C) 1995 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
CHARACTER*(*) K0,K
DOUBLE PRECISION E
DOUBLE PRECISION sla_EPB,sla_EPJ2D,sla_EPJ,sla_EPB2D
IF (K.EQ.K0) THEN
sla_EPCO=E
ELSE IF (K0.EQ.'B'.OR.K0.EQ.'b') THEN
sla_EPCO=sla_EPB(sla_EPJ2D(E))
ELSE
sla_EPCO=sla_EPJ(sla_EPB2D(E))
END IF
END
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