rfa 0.5.9

A port ERFA to Rust.
Documentation 
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use crate::prec_nut::{pr00::*, nut00a::*, obl80::*, };
use super::ee00::*;
///  Equation of the equinoxes, compatible with IAU 2000 resolutions.
///
///  Given:
///   * date1,date2  TT as a 2-part Julian Date (Note 1)
///
///  Returned (function value):
///   * equation of the equinoxes (Note 2)
///
/// # Notes:
///
///  1) The TT date date1+date2 is a Julian Date, apportioned in any
///     convenient way between the two arguments.  For example,
///     JD(TT)=2450123.7 could be expressed in any of these ways,
///     among others:
///
///     |    date1    |      date2   |                      |
///     |-------------|--------------|----------------------|
///     |2450123.7    |       0.0    |  (JD method)         |
///     |2451545.0    |   -1421.3    |  (J2000 method)      |
///     |2400000.5    |   50123.2    |  (MJD method)        |
///     |2450123.5    |       0.2    | (date & time method) |
///
///     The JD method is the most natural and convenient to use in
///     cases where the loss of several decimal digits of resolution
///     is acceptable.  The J2000 method is best matched to the way
///     the argument is handled internally and will deliver the
///     optimum resolution.  The MJD method and the date & time methods
///     are both good compromises between resolution and convenience.
///
///  2) The result, which is in radians, operates in the following sense:
///
///        Greenwich apparent ST = GMST + equation of the equinoxes
///
///  3) The result is compatible with the IAU 2000 resolutions.  For
///     further details, see IERS Conventions 2003 and Capitaine et al.
///     (2002).
///
/// # Called:
///    * pr00      IAU 2000 precession adjustments
///    * obl80     mean obliquity, IAU 1980
///    * nut00a    nutation, IAU 2000A
///    * ee00      equation of the equinoxes, IAU 2000
///
/// # References:
///   * Capitaine, N., Wallace, P.T. and McCarthy, D.D., "Expressions to
///     implement the IAU 2000 definition of UT1", Astronomy &
///     Astrophysics, 406, 1135-1149 (2003).
///   * McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
///     IERS Technical Note No. 32, BKG (2004).
///
///  This revision:  2021 May 11
pub fn ee00a(date1: f64, date2: f64)->f64
{
    let mut dpsipr =0.0; let mut depspr =0.0; let mut dpsi = 0.0; let mut deps =0.0;
 
 
 /* IAU 2000 precession-rate adjustments. */
    pr00(date1, date2, &mut dpsipr, &mut depspr);
 
 /* Mean obliquity, consistent with IAU 2000 precession-nutation. */
    let epsa = obl80(date1, date2) + depspr;
 
 /* Nutation in longitude. */
    nut00a(date1, date2, &mut dpsi, &mut deps);
 
 /* Equation of the equinoxes. */
    ee00(date1, date2, epsa, dpsi)
 
/* Finished. */
 
 }