/rust/registry/src/index.crates.io-1949cf8c6b5b557f/sofars-0.6.2/src/pnp/pn06a.rs

Source
use super::{nut06a, pn06};

///  Precession-nutation, IAU 2006/2000A models:  a multi-purpose function,
///  supporting classical (equinox-based) use directly and CIO-based use
///  indirectly.
///
///  This function is part of the International Astronomical Union's
///  SOFA (Standards of Fundamental Astronomy) software collection.
///
///  Status:  support function.
///
///  Given:
///     date1,date2  double          TT as a 2-part Julian Date (Note 1)
///
///  Returned (function value):
///     (dpsi, deps, epsa, rb, rp, rbp, rn, rbpn) (f64, f64, f64, [[f64; 3]; 3], [[f64; 3]; 3], [[f64; 3]; 3], [[f64; 3]; 3], [[f64; 3]; 3])
///
///     dpsi,deps    nutation (Note 2)
///     epsa         mean obliquity (Note 3)
///     rb           frame bias matrix (Note 4)
///     rp           precession matrix (Note 5)
///     rbp          bias-precession matrix (Note 6)
///     rn           nutation matrix (Note 7)
///     rbpn         GCRS-to-true matrix (Notes 8,9)
///
///  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:
///
///      ```text
///             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 nutation components (luni-solar + planetary, IAU 2000A) in
///      longitude and obliquity are in radians and with respect to the
///      equinox and ecliptic of date.  Free core nutation is omitted;
///      for the utmost accuracy, use the iauPn06 function, where the
///      nutation components are caller-specified.
///
///  3)  The mean obliquity is consistent with the IAU 2006 precession.
///
///  4)  The matrix rb transforms vectors from GCRS to mean J2000.0 by
///      applying frame bias.
///
///  5)  The matrix rp transforms vectors from mean J2000.0 to mean of
///      date by applying precession.
///
///  6)  The matrix rbp transforms vectors from GCRS to mean of date by
///      applying frame bias then precession.  It is the product rp x rb.
///
///  7)  The matrix rn transforms vectors from mean of date to true of
///      date by applying the nutation (luni-solar + planetary).
///
///  8)  The matrix rbpn transforms vectors from GCRS to true of date
///      (CIP/equinox).  It is the product rn x rbp, applying frame bias,
///      precession and nutation in that order.
///
///  9)  The X,Y,Z coordinates of the IAU 2006/2000A Celestial
///      Intermediate Pole are elements (3,1-3) of the GCRS-to-true
///      matrix, i.e. rbpn[2][0-2].
///
///  10) It is permissible to re-use the same array in the returned
///      arguments.  The arrays are filled in the stated order.
///
///  Called:
///     iauNut06a    nutation, IAU 2006/2000A
///     iauPn06      bias/precession/nutation results, IAU 2006
///
///  Reference:
///
///     Capitaine, N. & Wallace, P.T., 2006, Astron.Astrophys. 450, 855
pub fn pn06a(
    date1: f64,
    date2: f64,
) -> (
    f64,
    f64,
    f64,
    [[f64; 3]; 3],
    [[f64; 3]; 3],
    [[f64; 3]; 3],
    [[f64; 3]; 3],
    [[f64; 3]; 3],
) {
    /* Nutation. */
    let (dpsi, deps) = nut06a(date1, date2);

    /* Remaining results. */
    let (epsa, rb, rp, rbp, rn, rbpn) = pn06(date1, date2, dpsi, deps);

    (dpsi, deps, epsa, rb, rp, rbp, rn, rbpn)
}

Coverage Report

Created: 2026-10-28 06:40

Line	Count	Source
1		use super::{nut06a, pn06};
2
3		/// Precession-nutation, IAU 2006/2000A models: a multi-purpose function,
4		/// supporting classical (equinox-based) use directly and CIO-based use
5		/// indirectly.
6		///
7		/// This function is part of the International Astronomical Union's
8		/// SOFA (Standards of Fundamental Astronomy) software collection.
9		///
10		/// Status: support function.
11		///
12		/// Given:
13		/// date1,date2 double TT as a 2-part Julian Date (Note 1)
14		///
15		/// Returned (function value):
16		/// (dpsi, deps, epsa, rb, rp, rbp, rn, rbpn) (f64, f64, f64, [[f64; 3]; 3], [[f64; 3]; 3], [[f64; 3]; 3], [[f64; 3]; 3], [[f64; 3]; 3])
17		///
18		/// dpsi,deps nutation (Note 2)
19		/// epsa mean obliquity (Note 3)
20		/// rb frame bias matrix (Note 4)
21		/// rp precession matrix (Note 5)
22		/// rbp bias-precession matrix (Note 6)
23		/// rn nutation matrix (Note 7)
24		/// rbpn GCRS-to-true matrix (Notes 8,9)
25		///
26		/// Notes:
27		///
28		/// 1) The TT date date1+date2 is a Julian Date, apportioned in any
29		/// convenient way between the two arguments. For example,
30		/// JD(TT)=2450123.7 could be expressed in any of these ways,
31		/// among others:
32		///
33		/// ```text
34		/// date1 date2
35		///
36		/// 2450123.7 0.0 (JD method)
37		/// 2451545.0 -1421.3 (J2000 method)
38		/// 2400000.5 50123.2 (MJD method)
39		/// 2450123.5 0.2 (date & time method)
40		/// ```
41		///
42		/// The JD method is the most natural and convenient to use in
43		/// cases where the loss of several decimal digits of resolution
44		/// is acceptable. The J2000 method is best matched to the way
45		/// the argument is handled internally and will deliver the
46		/// optimum resolution. The MJD method and the date & time methods
47		/// are both good compromises between resolution and convenience.
48		///
49		/// 2) The nutation components (luni-solar + planetary, IAU 2000A) in
50		/// longitude and obliquity are in radians and with respect to the
51		/// equinox and ecliptic of date. Free core nutation is omitted;
52		/// for the utmost accuracy, use the iauPn06 function, where the
53		/// nutation components are caller-specified.
54		///
55		/// 3) The mean obliquity is consistent with the IAU 2006 precession.
56		///
57		/// 4) The matrix rb transforms vectors from GCRS to mean J2000.0 by
58		/// applying frame bias.
59		///
60		/// 5) The matrix rp transforms vectors from mean J2000.0 to mean of
61		/// date by applying precession.
62		///
63		/// 6) The matrix rbp transforms vectors from GCRS to mean of date by
64		/// applying frame bias then precession. It is the product rp x rb.
65		///
66		/// 7) The matrix rn transforms vectors from mean of date to true of
67		/// date by applying the nutation (luni-solar + planetary).
68		///
69		/// 8) The matrix rbpn transforms vectors from GCRS to true of date
70		/// (CIP/equinox). It is the product rn x rbp, applying frame bias,
71		/// precession and nutation in that order.
72		///
73		/// 9) The X,Y,Z coordinates of the IAU 2006/2000A Celestial
74		/// Intermediate Pole are elements (3,1-3) of the GCRS-to-true
75		/// matrix, i.e. rbpn[2][0-2].
76		///
77		/// 10) It is permissible to re-use the same array in the returned
78		/// arguments. The arrays are filled in the stated order.
79		///
80		/// Called:
81		/// iauNut06a nutation, IAU 2006/2000A
82		/// iauPn06 bias/precession/nutation results, IAU 2006
83		///
84		/// Reference:
85		///
86		/// Capitaine, N. & Wallace, P.T., 2006, Astron.Astrophys. 450, 855
87	0	pub fn pn06a(
88	0	date1: f64,
89	0	date2: f64,
90	0	) -> (
91	0	f64,
92	0	f64,
93	0	f64,
94	0	[[f64; 3]; 3],
95	0	[[f64; 3]; 3],
96	0	[[f64; 3]; 3],
97	0	[[f64; 3]; 3],
98	0	[[f64; 3]; 3],
99	0	) {
100		/* Nutation. */
101	0	let (dpsi, deps) = nut06a(date1, date2);
102
103		/* Remaining results. */
104	0	let (epsa, rb, rp, rbp, rn, rbpn) = pn06(date1, date2, dpsi, deps);
105
106	0	(dpsi, deps, epsa, rb, rp, rbp, rn, rbpn)
107	0	}