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.

```

#### I/O

```
Given:

r     distance of the point of interest from z axis.

[1,n] = size(r); double = class(r)

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

[1,n] = size(lon); double = class(lon)

z     height of the point above xy plane.

[1,n] = size(z); double = class(z)

the call:

jacobi = cspice_drdcyl( r, lon, z)

returns:

jacobi   the matrix of partial derivatives of the conversion between
cylindrical and rectangular coordinates. It has the form

If [1,1] = size(r) then [3,3]   = size(jacobi)
If [1,n] = size(r) then [3,3,n] = size(jacobi)
double = class(jacobi)

-                               -
|  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)

```

#### Required Reading

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

MICE.REQ

```

#### Version

```
-Mice Version 1.0.0, 09-NOV-2012, EDW (JPL), SCK (JPL)

```

#### Index_Entries

```
Jacobian of rectangular w.r.t. cylindrical coordinates

```
`Wed Apr  5 18:00:30 2017`