- Abstract
Find the unit vector along a double precision vector of
arbitrary dimension.
- Required_Reading
None.
- Brief_I/O
VARIABLE I/O DESCRIPTION
-------- --- --------------------------------------------------
v1 I Vector to be normalized.
ndim I Dimension of v1 (and also vout).
vout O Unit vector v1 / |v1|.
If v1 = 0, vout will also be zero.
vout can overwrite v1.
- Detailed_Input
v1 This is any double precision vector of arbitrary
dimension. This routine will detect if is V1 the
zero vector, and will not attempt to divide by zero.
ndim is the dimension of V1 (and also VOUT).
- Detailed_Output
vout contains the unit vector in the direction of v1. If
v1 represents the zero vector, then vout will also be
the zero vector. vout may overwrite v1.
- Parameters
None.
- Particulars
vhatg_c determines the magnitude of V1 and then divides each
component of V1 by the magnitude. This process is highly stable
over the whole range of multi-dimensional vectors.
- Examples
The following table shows how selected v1 maps to vout.
v1 ndim vout
-----------------------------------------------------------------
(5, 12, 0, 0) 4 (5/13, 12/13, 0, 0)
(1e-7, 2D-e, 2e-7) 3 (1/3, 2/3, 2/3)
- Restrictions
The relative number of cases whereby floating point overflow may
occur is negligible. Thus, no error recovery or reporting scheme
is incorporated into this subroutine.
- Exceptions
Error free.
- Files
None.
- Author_and_Institution
N.J. Bachman (JPL)
W.M. Owen (JPL)
- Literature_References
None.
- Version
-CSPICE Version 1.0.0, 13-JUL-1999 (NJB) (WMO)
- Index_Entries
unitize a n-dimensional vector
- Link to routine source