CART2CYL  Convert cartesian to cylindrical coordinates.

   CYL = cart2cyl(POINT)
   convert the 3D cartesian coordinates of points POINT (given by [X Y Z]
   where X, Y, Z have the same size) into cylindrical coordinates CYL,
   given by [THETA R Z]. 
   THETA is the arctangent of the ratio Y/X (between 0 and 2*PI)
   R     can be computed using sqrt(X^2+Y^2)
   Z     keeps the same value.
   The size of THETA, and R is the same as the size of X, Y and Z.

   CYL = cart2cyl(X, Y, Z)
   provides coordinates as 3 different parameters

   Example
   cart2cyl([-1 0 2])
   gives : 4.7124    1.0000     2.0000

   See also agles3d, cart2pol, cart2sph2


 ------
 Author: David Legland
 e-mail: david.legland@jouy.inra.fr
 Created: 2006-03-23
 Copyright 2006 INRA - CEPIA Nantes - MIAJ (Jouy-en-Josas).

Package: matgeom