sofars 0.6.0

Pure Rust implementation of the IAU SOFA library
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71

use super::eect00;

///  Equation of the equinoxes, IAU 2000
///
///  The equation of the equinoxes, compatible with IAU 2000 resolutions,
///  given the nutation in longitude and the mean obliquity.
///
///  This function is part of the International Astronomical Union's
///  SOFA (Standards of Fundamental Astronomy) software collection.
///
///  Status:  canonical model.
///
///  Given:
///  ```
///     date1,date2  double    TT as a 2-part Julian Date (Note 1)
///     epsa         double    mean obliquity (Note 2)
///     dpsi         double    nutation in longitude (Note 3)
///  ```
///  Returned (function value):
///  ```
///  
///                  double    equation of the equinoxes (Note 4)
///  ```
///  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 obliquity, in radians, is mean of date.
///
///  3) The result, which is in radians, operates in the following sense:
///
///        Greenwich apparent ST = GMST + equation of the equinoxes
///
///  4) The result is compatible with the IAU 2000 resolutions.  For
///     further details, see IERS Conventions 2003 and Capitaine et al.
///     (2002).
///
///  Called:
///  ```
///  
///     iauEect00    equation of the equinoxes complementary terms
///  ```
///  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)
pub fn ee00(date1: f64, date2: f64, epsa: f64, dpsi: f64) -> f64 {
    /* Equation of the equinoxes. */
    dpsi * epsa.cos() + eect00(date1, date2)
}