cspice_drdcyl

 Abstract I/O Examples Particulars Required Reading Version Index_Entries

#### Abstract

CSPICE_DRDCYL computes the Jacobian of the transformation from
cylindrical to rectangular coordinates.

For important details concerning this module's function, please refer to
the CSPICE routine drdcyl_c.

#### I/O

Given:

r     scalar double precision describing the distance of the
point of interest from z axis.

lon   scalar double precision describing the cylindrical angle
(in radians) of the point of interest from the xz plane. The angle
increases in the counterclockwise sense about the +z axis.

z     scalar double precision describing the height of the point
above xy plane.

the call:

cspice_drdcyl, r, lon, z, jacobi

returns:

jacobi   double precision 3x3 matrix describing the matrix of partial
derivatives of the conversion between cylindrical and
rectangular coordinates. It has the form

-                               -
|  dx/dr     dx/dlon     dx/dz    |
|                                 |
|  dy/dr     dy/dlon     dy/dz    |
|                                 |
|  dz/dr     dz/dlon     dz/dz    |
-                               -

evaluated at the input values of 'r', 'lon' and 'z'.  Here
'x', 'y', and 'z' are given by the familiar formulae

x = r*cos(lon)
y = r*sin(lon)
z = z

None.

#### Particulars

It is often convenient to describe the motion of an object in
the cylindrical coordinate system.  However, when performing
vector computations its hard to beat rectangular coordinates.

To transform states given with respect to cylindrical coordinates
to states with respect to rectangular coordinates, one uses
the Jacobian of the transformation between the two systems.

Given a state in cylindrical coordinates

( r, lon, z, dr, dlon, dz )

the velocity in rectangular coordinates is given by the matrix
equation:
t          |                          t
(dx, dy, dz)   = jacobi|          * (dr, dlon, dz)
|(r,lon,z)

This routine computes the matrix

|
jacobi|
|(r,lon,z)

ICY.REQ

#### Version

-Icy Version 1.0.0, 11-NOV-2013, EDW (JPL)

#### Index_Entries

Jacobian of rectangular w.r.t. cylindrical coordinates

Wed Apr  5 17:58:00 2017