vupack_c

Index Page vupack_c
A B C D E F G H I J K L M N O P Q R S T U V W X
Procedure Abstract Required_Reading Keywords Brief_I/O Detailed_Input | Detailed_Output Parameters Exceptions Files Particulars Examples | Restrictions Literature_References Author_and_Institution Version Index_Entries
#### Procedure
       void vupack_c ( ConstSpiceDouble     v[3],
                       SpiceDouble        * x,
                       SpiceDouble        * y,
                       SpiceDouble        * z     )
#### Abstract
       Unpack three scalar components from a vector.
#### Required_Reading
       None.
#### Keywords
       VECTOR
#### Brief_I/O
       VARIABLE  I/O  DESCRIPTION
       --------  ---  --------------------------------------------------
       v          I   3-vector.
       x,
       y,
       z          O   Scalar components of 3-vector.
#### Detailed_Input
       v           is a double precision 3-vector.
#### Detailed_Output
       x,
       y,
       z           are the scalar components of the 3-vector v.  On output,
                   the following equalities hold:

                      x = v[0]
                      y = v[1]
                      z = v[2]
#### Parameters
       None.
#### Exceptions
       Error free.
#### Files
       None.
#### Particulars
       Basically, this is just shorthand notation for the common
       sequence

          x = v[0];
          y = v[1];
          z = v[2] ;

       The routine is useful largely for two reasons. First, it
       reduces the chance that the programmer will make a "cut and
       paste" mistake, like

          x = v[0];
          y = v[0];
          z = v[0];

       Second, it makes conversions between equivalent units simpler,
       and clearer. For instance, the sequence

          x = v[0] * rpd_c();
          y = v[1] * rpd_c();
          z = v[2] * rpd_c();

       can be replaced by the (nearly) equivalent sequence

          vscl_c   ( rpd_c(),  v,   v  );
          vupack_c ( v,  &x,  &y,  &z  );
#### Examples
       See: Detailed_Description.
#### Restrictions
       None.
#### Literature_References
       None.
#### Author_and_Institution
       N.J. Bachman    (JPL)
       I.M. Underwood  (JPL)
#### Version
       -CSPICE Version 1.0.0, 07-NOV-2006 (NJB)

          Corrected header errors that claimed this routine
          performs the function of vpack_c.

       -CSPICE Version 1.0.0, 28-JUN-1999 (IMU) (NJB)
#### Index_Entries
       unpack three scalar components from a vector
#### Link to routine vupack_c source file vupack_c.c

    Thu Apr 16 08:59:37 2009