Procedure

   void cylrec_c ( SpiceDouble r,
                   SpiceDouble lon,
                   SpiceDouble z,
                   SpiceDouble rectan[3] )

Abstract

   Convert from cylindrical to rectangular coordinates.

Required_Reading

   None.

Keywords

   CONVERSION
   COORDINATES

Brief_I/O

   VARIABLE  I/O  DESCRIPTION
   --------  ---  -------------------------------------------------
   r          I   Distance of a point from z axis.
   lon        I   Angle (radians) of a point from xZ plane
   z          I   Height of a point above xY plane.
   rectan     O   Rectangular coordinates of the point.

Detailed_Input

   r          Distance of the point of interest from z axis.

   lon        Cylindrical angle (in radians) of the point of
              interest from XZ plane.

   z          Height of the point above XY plane.

Detailed_Output

   rectan     Rectangular coordinates of the point of interest.

Parameters

   None.

Exceptions

   Error free.

Files

   None.

Particulars

   This routine transforms the coordinates of a point from
   cylindrical to rectangular coordinates.

Examples

   Below are two tables.

   Listed in the first table (under r, lon and z ) are
   cylindrical coordinate triples that approximately represent
   points whose rectangular coordinates are taken from the set
   {-1, 0, 1}.  (Angular quantities are given in degrees.)

   The result of the code fragment

        Use the CSPICE routine convrt_c to convert the angular
        quantities to radians

        convrt_c (  lon, "DEGREES", "RADIANS", lon );

        cylrec_c ( r, lon, z, x );


   are listed in the second parallel table under x(1), x(2) and x(3).


     r         lon     z            x(1)       x(2)     x(3)
     -------------------------       --------------------------
     0.0000    0.0000   0.0000       0.0000     0.0000   0.0000
     1.0000    0.0000   0.0000       1.0000     0.0000   0.0000
     1.0000   90.0000   0.0000       0.0000     1.0000   0.0000
     0.0000    0.0000   1.0000       0.0000     0.0000   1.0000
     1.0000  180.0000   0.0000      -1.0000     0.0000   0.0000
     1.0000  270.0000   0.0000       0.0000    -1.0000   0.0000
     0.0000    0.0000  -1.0000       0.0000     0.0000  -1.0000
     1.4142   45.0000   0.0000       1.0000     1.0000   0.0000
     1.0000    0.0000   1.0000       1.0000     0.0000   1.0000
     1.0000   90.0000   1.0000       0.0000     1.0000   1.0000
     1.4142   45.0000   1.0000       1.0000     1.0000   1.0000

Restrictions

   None.

Literature_References

   None.

Author_and_Institution

   E.D. Wright     (JPL)
   W.L. Taber      (JPL)

Version

   -CSPICE Version 1.0.1, 08-FEB-1998 (EDW)

       Corrected and clarified header entries.  Removed return call.

   -CSPICE Version 1.0.0, 25-OCT-1997 (EDW)

Index_Entries

   cylindrical to rectangular

Link to routine cylrec_c source file cylrec_c.c