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.
Given:
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.
the call:
cspice_drdlat, r, lon, lat, jacobi
returns:
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).
None.
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)
ICY.REQ
Icy Version 1.0.0, 11NOV2013, EDW (JPL)
Jacobian of rectangular w.r.t. latitudinal coordinates
