slaEcmat -

SYNOPSYS

PARAMETERS

double date

double ( *rmat

DESCRIPTION

  Form the equatorial to ecliptic rotation matrix (IAU 1980 theory).

  (double precision)

Given

     date     double         TDB (loosely ET) as Modified Julian Date
                                            (JD-2400000.5)

Returned

     rmat     double[3][3]   matrix

References

     Murray, C.A., Vectorial Astrometry, section 4.3.

Note

    The matrix is in the sense   v[ecl]  =  rmat * v[equ];  the
    equator, equinox and ecliptic are mean of date.

Called

 slaDeuler

  Defined in slamac.h:  DAS2R

  P.T.Wallace   Starlink   31 October 1993

SEE ALSO

• slalib.3