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//
// GENERATED FILE
//
use super::*;
use crate::SpiceContext;
use f2rust_std::*;
const DX: i32 = 1;
const DY: i32 = 2;
const DZ: i32 = 3;
const DR: i32 = 1;
const DLON: i32 = 2;
const DLAT: i32 = 3;
/// Derivative of rectangular w.r.t. latitudinal
///
/// Compute the Jacobian matrix of the transformation from
/// latitudinal to rectangular coordinates.
///
/// # Brief I/O
///
/// ```text
/// VARIABLE I/O DESCRIPTION
/// -------- --- --------------------------------------------------
/// R I Distance of a point from the origin.
/// LON I Angle of the point from the XZ plane in radians.
/// LAT I Angle of the point from the XY plane in radians.
/// JACOBI O Matrix of partial derivatives.
/// ```
///
/// # Detailed Input
///
/// ```text
/// R is the distance of a point from the origin.
///
/// LON is the angle of the point from the XZ plane in
/// radians. The angle increases in the counterclockwise
/// sense about the +Z axis.
///
/// LAT is the angle of the point from the XY plane in
/// radians. The angle increases in the direction of the
/// +Z axis.
/// ```
///
/// # Detailed Output
///
/// ```text
/// JACOBI is the matrix of partial derivatives of the conversion
/// between latitudinal and rectangular coordinates. It has
/// the form
///
/// .- -.
/// | DX/DR DX/DLON DX/DLAT |
/// | |
/// | DY/DR DY/DLON DY/DLAT |
/// | |
/// | DZ/DR DZ/DLON DZ/DLAT |
/// `- -'
///
/// evaluated at the input values of R, LON and LAT.
/// Here X, Y, and Z are given by the familiar formulae
///
/// X = R * COS(LON) * COS(LAT)
/// Y = R * SIN(LON) * COS(LAT)
/// Z = R * SIN(LAT)
/// ```
///
/// # Exceptions
///
/// ```text
/// Error free.
/// ```
///
/// # Particulars
///
/// ```text
/// It is often convenient to describe the motion of an object
/// in latitudinal coordinates. It is also convenient to manipulate
/// vectors associated with the object in rectangular coordinates.
///
/// The transformation of a latitudinal state into an equivalent
/// rectangular state makes use of the Jacobian of the
/// transformation between the two systems.
///
/// Given a state in latitudinal coordinates,
///
/// ( r, lon, lat, dr, dlon, dlat )
///
/// the velocity in rectangular coordinates is given by the matrix
/// equation
/// t | t
/// (dx, dy, dz) = JACOBI| * (dr, dlon, dlat)
/// |(r,lon,lat)
///
/// This routine computes the matrix
///
/// |
/// JACOBI|
/// |(r,lon,lat)
/// ```
///
/// # Examples
///
/// ```text
/// The numerical results shown for this example may differ across
/// platforms. The results depend on the SPICE kernels used as
/// input, the compiler and supporting libraries, and the machine
/// specific arithmetic implementation.
///
/// 1) Find the latitudinal state of the Earth as seen from
/// Mars in the IAU_MARS reference frame at January 1, 2005 TDB.
/// Map this state back to rectangular coordinates as a check.
///
/// Use the meta-kernel shown below to load the required SPICE
/// kernels.
///
///
/// KPL/MK
///
/// File name: drdlat_ex1.tm
///
/// This meta-kernel is intended to support operation of SPICE
/// example programs. The kernels shown here should not be
/// assumed to contain adequate or correct versions of data
/// required by SPICE-based user applications.
///
/// In order for an application to use this meta-kernel, the
/// kernels referenced here must be present in the user's
/// current working directory.
///
/// The names and contents of the kernels referenced
/// by this meta-kernel are as follows:
///
/// File name Contents
/// --------- --------
/// de421.bsp Planetary ephemeris
/// pck00010.tpc Planet orientation and
/// radii
/// naif0009.tls Leapseconds
///
///
/// \begindata
///
/// KERNELS_TO_LOAD = ( 'de421.bsp',
/// 'pck00010.tpc',
/// 'naif0009.tls' )
///
/// \begintext
///
/// End of meta-kernel
///
///
/// Example code begins here.
///
///
/// PROGRAM DRDLAT_EX1
/// IMPLICIT NONE
///
/// C
/// C SPICELIB functions
/// C
/// DOUBLE PRECISION RPD
///
/// C
/// C Local parameters
/// C
/// CHARACTER*(*) FMT1
/// PARAMETER ( FMT1 = '(A,E18.8)' )
/// C
/// C Local variables
/// C
/// DOUBLE PRECISION DRECTN ( 3 )
/// DOUBLE PRECISION ET
/// DOUBLE PRECISION JACOBI ( 3, 3 )
/// DOUBLE PRECISION LAT
/// DOUBLE PRECISION LON
/// DOUBLE PRECISION LT
/// DOUBLE PRECISION LATVEL ( 3 )
/// DOUBLE PRECISION RECTAN ( 3 )
/// DOUBLE PRECISION R
/// DOUBLE PRECISION STATE ( 6 )
///
/// C
/// C Load SPK, PCK and LSK kernels, use a meta kernel for
/// C convenience.
/// C
/// CALL FURNSH ( 'drdlat_ex1.tm' )
///
/// C
/// C Look up the apparent state of earth as seen from Mars at
/// C January 1, 2005 TDB, relative to the IAU_MARS reference
/// C frame.
/// C
/// CALL STR2ET ( 'January 1, 2005 TDB', ET )
///
/// CALL SPKEZR ( 'Earth', ET, 'IAU_MARS', 'LT+S',
/// . 'Mars', STATE, LT )
///
/// C
/// C Convert position to latitudinal coordinates.
/// C
/// CALL RECLAT ( STATE, R, LON, LAT )
///
/// C
/// C Convert velocity to latitudinal coordinates.
/// C
///
/// CALL DLATDR ( STATE(1), STATE(2), STATE(3), JACOBI )
///
/// CALL MXV ( JACOBI, STATE(4), LATVEL )
///
/// C
/// C As a check, convert the latitudinal state back to
/// C rectangular coordinates.
/// C
/// CALL LATREC ( R, LON, LAT, RECTAN )
///
/// CALL DRDLAT ( R, LON, LAT, JACOBI )
///
/// CALL MXV ( JACOBI, LATVEL, DRECTN )
///
///
/// WRITE(*,*) ' '
/// WRITE(*,*) 'Rectangular coordinates:'
/// WRITE(*,*) ' '
/// WRITE(*,FMT1) ' X (km) = ', STATE(1)
/// WRITE(*,FMT1) ' Y (km) = ', STATE(2)
/// WRITE(*,FMT1) ' Z (km) = ', STATE(3)
/// WRITE(*,*) ' '
/// WRITE(*,*) 'Rectangular velocity:'
/// WRITE(*,*) ' '
/// WRITE(*,FMT1) ' dX/dt (km/s) = ', STATE(4)
/// WRITE(*,FMT1) ' dY/dt (km/s) = ', STATE(5)
/// WRITE(*,FMT1) ' dZ/dt (km/s) = ', STATE(6)
/// WRITE(*,*) ' '
/// WRITE(*,*) 'Latitudinal coordinates:'
/// WRITE(*,*) ' '
/// WRITE(*,FMT1) ' Radius (km) = ', R
/// WRITE(*,FMT1) ' Longitude (deg) = ', LON/RPD()
/// WRITE(*,FMT1) ' Latitude (deg) = ', LAT/RPD()
/// WRITE(*,*) ' '
/// WRITE(*,*) 'Latitudinal velocity:'
/// WRITE(*,*) ' '
/// WRITE(*,FMT1) ' d Radius/dt (km/s) = ', LATVEL(1)
/// WRITE(*,FMT1) ' d Longitude/dt (deg/s) = ',
/// . LATVEL(2)/RPD()
/// WRITE(*,FMT1) ' d Latitude/dt (deg/s) = ',
/// . LATVEL(3)/RPD()
/// WRITE(*,*) ' '
/// WRITE(*,*) 'Rectangular coordinates from inverse ' //
/// . 'mapping:'
/// WRITE(*,*) ' '
/// WRITE(*,FMT1) ' X (km) = ', RECTAN(1)
/// WRITE(*,FMT1) ' Y (km) = ', RECTAN(2)
/// WRITE(*,FMT1) ' Z (km) = ', RECTAN(3)
/// WRITE(*,*) ' '
/// WRITE(*,*) 'Rectangular velocity from inverse mapping:'
/// WRITE(*,*) ' '
/// WRITE(*,FMT1) ' dX/dt (km/s) = ', DRECTN(1)
/// WRITE(*,FMT1) ' dY/dt (km/s) = ', DRECTN(2)
/// WRITE(*,FMT1) ' dZ/dt (km/s) = ', DRECTN(3)
/// WRITE(*,*) ' '
/// END
///
///
/// When this program was executed on a Mac/Intel/gfortran/64-bit
/// platform, the output was:
///
///
/// Rectangular coordinates:
///
/// X (km) = -0.76096183E+08
/// Y (km) = 0.32436380E+09
/// Z (km) = 0.47470484E+08
///
/// Rectangular velocity:
///
/// dX/dt (km/s) = 0.22952075E+05
/// dY/dt (km/s) = 0.53760111E+04
/// dZ/dt (km/s) = -0.20881149E+02
///
/// Latitudinal coordinates:
///
/// Radius (km) = 0.33653522E+09
/// Longitude (deg) = 0.10320290E+03
/// Latitude (deg) = 0.81089866E+01
///
/// Latitudinal velocity:
///
/// d Radius/dt (km/s) = -0.11211601E+02
/// d Longitude/dt (deg/s) = -0.40539288E-02
/// d Latitude/dt (deg/s) = -0.33189930E-05
///
/// Rectangular coordinates from inverse mapping:
///
/// X (km) = -0.76096183E+08
/// Y (km) = 0.32436380E+09
/// Z (km) = 0.47470484E+08
///
/// Rectangular velocity from inverse mapping:
///
/// dX/dt (km/s) = 0.22952075E+05
/// dY/dt (km/s) = 0.53760111E+04
/// dZ/dt (km/s) = -0.20881149E+02
/// ```
///
/// # Author and Institution
///
/// ```text
/// J. Diaz del Rio (ODC Space)
/// W.L. Taber (JPL)
/// ```
///
/// # Version
///
/// ```text
/// - SPICELIB Version 1.1.0, 26-OCT-2020 (JDR)
///
/// Changed the input argument name LONG to LON for consistency
/// with other routines.
///
/// Edited the header to comply with NAIF standard. Added complete
/// code example.
///
/// Updated $Brief_I/O and $Detailed_Input sections to correct R
/// argument name, which in previous version was RADIUS.
///
/// - SPICELIB Version 1.0.0, 19-JUL-2001 (WLT)
/// ```
pub fn drdlat(r: f64, lon: f64, lat: f64, jacobi: &mut [[f64; 3]; 3]) {
DRDLAT(r, lon, lat, jacobi.as_flattened_mut());
}
//$Procedure DRDLAT ( Derivative of rectangular w.r.t. latitudinal )
pub fn DRDLAT(R: f64, LON: f64, LAT: f64, JACOBI: &mut [f64]) {
let mut JACOBI = DummyArrayMut2D::new(JACOBI, 1..=3, 1..=3);
//
// Local variables
//
//
// Construct the matrix directly.
//
JACOBI[[DX, DR]] = (f64::cos(LON) * f64::cos(LAT));
JACOBI[[DY, DR]] = (f64::sin(LON) * f64::cos(LAT));
JACOBI[[DZ, DR]] = f64::sin(LAT);
JACOBI[[DX, DLON]] = -((R * f64::sin(LON)) * f64::cos(LAT));
JACOBI[[DY, DLON]] = ((R * f64::cos(LON)) * f64::cos(LAT));
JACOBI[[DZ, DLON]] = 0.0;
JACOBI[[DX, DLAT]] = -((R * f64::cos(LON)) * f64::sin(LAT));
JACOBI[[DY, DLAT]] = -((R * f64::sin(LON)) * f64::sin(LAT));
JACOBI[[DZ, DLAT]] = (R * f64::cos(LAT));
}