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//
// GENERATED FILE
//
use super::*;
use crate::SpiceContext;
use f2rust_std::*;
/// Derivative of latitudinal w.r.t. rectangular
///
/// Compute the Jacobian matrix of the transformation from
/// rectangular to latitudinal coordinates.
///
/// # Brief I/O
///
/// ```text
/// VARIABLE I/O DESCRIPTION
/// -------- --- --------------------------------------------------
/// X I X-coordinate of point.
/// Y I Y-coordinate of point.
/// Z I Z-coordinate of point.
/// JACOBI O Matrix of partial derivatives.
/// ```
///
/// # Detailed Input
///
/// ```text
/// X,
/// Y,
/// Z are the rectangular coordinates of the point at
/// which the Jacobian of the map from rectangular
/// to latitudinal coordinates is desired.
/// ```
///
/// # Detailed Output
///
/// ```text
/// JACOBI is the matrix of partial derivatives of the conversion
/// between rectangular and latitudinal coordinates. It
/// has the form
///
/// .- -.
/// | dr/dx dr/dy dr/dz |
/// | dlong/dx dlong/dy dlong/dz |
/// | dlat/dx dlat/dy dlat/dz |
/// `- -'
///
/// evaluated at the input values of X, Y, and Z.
/// ```
///
/// # Exceptions
///
/// ```text
/// 1) If the input point is on the z-axis (X = 0 and Y = 0), the
/// Jacobian is undefined, the error SPICE(POINTONZAXIS) is
/// signaled.
/// ```
///
/// # Particulars
///
/// ```text
/// When performing vector calculations with velocities it is
/// usually most convenient to work in rectangular coordinates.
/// However, once the vector manipulations have been performed
/// it is often desirable to convert the rectangular representations
/// into latitudinal coordinates to gain insights about phenomena
/// in this coordinate frame.
///
/// To transform rectangular velocities to derivatives of coordinates
/// in a latitudinal system, one uses the Jacobian of the
/// transformation between the two systems.
///
/// Given a state in rectangular coordinates
///
/// ( x, y, z, dx, dy, dz )
///
/// the corresponding latitudinal coordinate derivatives are given by
/// the matrix equation:
///
/// t | t
/// (dr, dlong, dlat) = JACOBI| * (dx, dy, dz)
/// |(x,y,z)
///
/// This routine computes the matrix
///
/// |
/// JACOBI|
/// |(x, y, z)
/// ```
///
/// # 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: dlatdr_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 DLATDR_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 ( 'dlatdr_ex1.tm' )
///
/// C
/// C Look up the apparent state of earth as seen from Mars
/// C at January 1, 2005 TDB, relative to the IAU_MARS
/// C reference 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 1.0.1, 26-OCT-2021 (JDR)
///
/// Edited the header to comply with NAIF standard.
/// Added complete code example.
///
/// - SPICELIB Version 1.0.0, 16-JUL-2001 (WLT)
/// ```
pub fn dlatdr(
ctx: &mut SpiceContext,
x: f64,
y: f64,
z: f64,
jacobi: &mut [[f64; 3]; 3],
) -> crate::Result<()> {
DLATDR(x, y, z, jacobi.as_flattened_mut(), ctx.raw_context())?;
ctx.handle_errors()?;
Ok(())
}
//$Procedure DLATDR ( Derivative of latitudinal w.r.t. rectangular )
pub fn DLATDR(
X: f64,
Y: f64,
Z: f64,
JACOBI: &mut [f64],
ctx: &mut Context,
) -> f2rust_std::Result<()> {
let mut JACOBI = DummyArrayMut2D::new(JACOBI, 1..=3, 1..=3);
let mut RECTAN = StackArray::<f64, 3>::new(1..=3);
let mut R: f64 = 0.0;
let mut LONG: f64 = 0.0;
let mut LAT: f64 = 0.0;
let mut INJACB = StackArray2D::<f64, 9>::new(1..=3, 1..=3);
//
// SPICELIB functions
//
//
// Local variables
//
//
// Standard SPICE error handling.
//
if RETURN(ctx) {
return Ok(());
} else {
CHKIN(b"DLATDR", ctx)?;
}
//
// There is a singularity of the Jacobian for points on the z-axis.
//
if ((X == 0 as f64) && (Y == 0 as f64)) {
SETMSG(b"The Jacobian of the transformation from rectangular to latitudinal coordinates is not defined for points on the z-axis.", ctx);
SIGERR(b"SPICE(POINTONZAXIS)", ctx)?;
CHKOUT(b"DLATDR", ctx)?;
return Ok(());
}
//
// We will get the Jacobian of the transformation from rectangular
// to latitudinal coordinates by implicit differentiation.
//
// First move the X,Y and Z coordinates into a vector.
//
VPACK(X, Y, Z, RECTAN.as_slice_mut());
//
// Convert from rectangular to latitudinal coordinates.
//
RECLAT(RECTAN.as_slice(), &mut R, &mut LONG, &mut LAT);
//
// Get the Jacobian of the transformation from latitudinal to
// rectangular coordinates at R, LONG, LAT.
//
DRDLAT(R, LONG, LAT, INJACB.as_slice_mut());
//
// Now invert INJACB to get the Jacobian of the transformation from
// rectangular to latitudinal coordinates.
//
INVORT(INJACB.as_slice(), JACOBI.as_slice_mut(), ctx)?;
CHKOUT(b"DLATDR", ctx)?;
Ok(())
}