- Abstract
Normalize a double precision 3-vector and return its magnitude.
- Required_Reading
None.
- Brief_I/O
VARIABLE I/O DESCRIPTION
-------- --- --------------------------------------------------
v1 I Vector to be normalized.
vout O Unit vector v1 / |v1|.
If v1 is the zero vector, then vout will also
be zero. vout can overwrite v1.
vmag O Magnitude of v1, i.e. |v1|.
- Detailed_Input
v1 This variable may contain any 3-vector, including the
zero vector.
- Detailed_Output
vout This variable contains the unit vector in the direction
of v1. If v1 is the zero vector, then vout will also be
the zero vector.
vmag This is the magnitude of v1.
- Parameters
None.
- Particulars
unorm_c references a function called vnorm_c (which itself is
numerically stable) to calculate the norm of the input vector v1.
If the norm is equal to zero, then each component of the output
vector vout is set to zero. Otherwise, vout is calculated by
dividing v1 by the norm.
- Examples
The following table shows how selected v1 implies vout and mag.
v1 vout mag
------------------ ------------------ ------
(5, 12, 0) (5/13, 12/13, 0) 13
(1D-7, 2D-7, 2D-7) (1/3, 2/3, 2/3) 3D-7
- Restrictions
None
- Exceptions
Error free.
- Files
None
- Author_and_Institution
W.M. Owen (JPL)
W.L. Taber (JPL)
- Literature_References
None
- Version
-CSPICE Version 1.1.0, 22-OCT-1998 (NJB)
Made input vector const.
CSPICE Version 1.0.0, 17-OCT-1997 (EDW)
- Index_Entries
3-dimensional unit vector and norm
- Link to routine source