Procedure

     PCKE02 ( PCK, evaluate data record from type 2 segment )

     SUBROUTINE PCKE02 ( ET, RECORD, EULANG )

Abstract

     Evaluate a single PCK data record from a segment of type 2
     (Chebyshev Polynomials, position only).

Required_Reading

     PCK

Keywords

     ROTATION
     TRANSFORMATION

Declarations

     IMPLICIT NONE

     DOUBLE PRECISION      ET
     DOUBLE PRECISION      RECORD   ( * )
     DOUBLE PRECISION      EULANG   ( 6 )

Brief_I/O

     VARIABLE  I/O  DESCRIPTION
     --------  ---  --------------------------------------------------
     ET         I   Epoch.
     RECORD     I   Data record.
     EULANG     O   Euler angles and their derivatives.

Detailed_Input

     ET       is an epoch, at which the Euler angles are to
              be computed.

     RECORD   is a data record which, when evaluated at epoch ET,
              will give the Euler angles of some body.

Detailed_Output

     EULANG   is the Euler angles and their derivatives at
              time ET.

Parameters

     None.

Exceptions

     Error free.

Files

     None.

Particulars

     The exact format and structure of type 2 (Chebyshev polynomials,
     position only) segments are described in the PCK Required Reading
     file.

     A type 2 segment contains three sets of Chebyshev coefficients,
     one set each for the Euler angles phi, delta and psi.  PCKE02
     calls the routine SPKE02 for each set to evaluate the polynomial
     AND its first derivative.

Examples

     The PCKEnn routines are almost always used in conjunction with
        the corresponding PCKRnn routines, which read the records from
        binary PCK files.

        The data returned by the PCKRnn routine is in its rawest form,
        taken directly from the segment. As such, it will be
        meaningless to a user unless he/she understands the structure
        of the data type completely. Given that understanding, however,
        the PCKRnn routines might be used to examine raw segment data
        before evaluating it with the PCKEnn routines.


     Here we load a binary PCK files and use PCKE02 to get the
     Euler angles.

     C
     C  Load binary PCK file.
     C
        CALL PCKLOF ('example.pck', HANDLE)


     C  Get a segment applicable to a specified body and epoch.

        CALL PCKSFS ( BODY, ET, HANDLE, DESCR, IDENT, FOUND )

        IF ( FOUND ) THEN


           Look at parts of the descriptor.

           CALL DAFUS ( DESCR, ND, NI, DCD, ICD )
           TYPE   = ICD( NT )
           REF    = ICD( NR )

           IF ( TYPE .EQ. 2 ) THEN

              Read in Chebyshev coefficients from segment.

              CALL PCKR02 ( HANDLE, DESCR, ET, RECORD )


              Call evaluation routine to get Euler angles
              phi, delta, w.

              CALL PCKE02 ( ET, RECORD, EULANG )


     The Euler angles and their derivatives are returned
     in EULANG.

Restrictions

     None.

Literature_References

     None.

Author_and_Institution

     J. Diaz del Rio    (ODC Space)
     E.D. Wright        (JPL)
     K.S. Zukor         (JPL)

Version

    SPICELIB Version 1.2.0, 20-AUG-2021 (JDR)

        Added IMPLICIT NONE statement.

        Edited the header to comply with NAIF standard.

    SPICELIB Version 1.1.1, 03-JAN-2014 (EDW)

        Minor edits to $Procedure; clean trailing whitespace.
        Removed unneeded $Revisions section.

    SPICELIB Version 1.1.0, 13-MAR-1995 (KSZ)

         Added error handling.

    SPICELIB Version 1.0.0, 30-SEP-1994 (KSZ)