CSPICE_DRDLAT computes the Jacobian of the transformation from latitudinal
to rectangular coordinates.
For important details concerning this module's function, please refer to
the CSPICE routine drdlat_c.
radius scalar double precision describing the distance of a
point from the origin.
lon scalar double precision describing the angle of the
point measured from the XZ plane in radians. The angle
increases in the counterclockwise sense about the +Z axis.
lat scalar double precision describing the angle of the
point measured from the XY plane in radians. The angle
increases in the direction of the +Z axis.
cspice_drdlat, r, lon, lat, jacobi
jacobi double precision 3x3 matrix describing the matrix of partial
derivatives of the conversion between latitudinal and
rectangular coordinates, evaluated at the input coordinates.
This matrix 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).
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
t | t
(dx, dy, dz) = jacobi| * (dr, dlon, dlat)
This routine computes the matrix
-Icy Version 1.0.0, 11-NOV-2013, EDW (JPL)
Jacobian of rectangular w.r.t. latitudinal coordinates