cspice_dcyldr

 Abstract I/O Examples Particulars Required Reading Version Index_Entries

#### Abstract

```
CSPICE_DCYLDR computes the Jacobian of the transformation from
rectangular to cylindrical coordinates.

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

```

#### I/O

```
Given:

x
y,
z   scalar double precision describing the rectangular coordinates
of the point at which the Jacobian of the map from rectangular
to cylindrical coordinates is desired.

the call:

cspice_dcyldr, x, y, z, jacobi

returns:

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

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

evaluated at the input values of 'x', 'y', and 'z'.

```

```
None.

```

#### Particulars

```
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 cylindrical coordinates to gain insights about phenomena
in this coordinate frame.

To transform rectangular velocities to derivatives of
coordinates in a cylindrical 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 velocity in cylindrical coordinates is given by the matrix
equation:

t          |                     t
(dr, dlon, dz)   = jacobi|       * (dx, dy, dz)
|(x,y,z)

This routine computes the matrix

|
jacobi|
|(x,y,z)

```

```
ICY.REQ

```

#### Version

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

```

#### Index_Entries

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

```
`Wed Apr  5 17:57:59 2017`