Procedure

   void reordd_c ( ConstSpiceInt      * iorder,
                   SpiceInt             ndim,
                   SpiceDouble        * array  ) 

Abstract

 
   Re-order the elements of a double precision array according to 
   a given order vector. 
 

Required_Reading

 
   None. 
 

Keywords

 
    ARRAY,  SORT 
 

Brief_I/O

 
   VARIABLE  I/O  DESCRIPTION 
   --------  ---  -------------------------------------------------- 
   iorder     I   Order vector to be used to re-order array. 
   ndim       I   Dimension of array. 
   array     I/O  Array to be re-ordered. 

Detailed_Input

 
   iorder      is the order vector to be used to re-order the input 
               array. The first element of iorder is the index of 
               the first item of the re-ordered array, and so on. 

               Note that the order imposed by reordd_c is not the 
               same order that would be imposed by a sorting 
               routine. In general, the order vector will have 
               been created (by one of the order routines) for 
               a related array, as illustrated in the example below. 

   ndim        is the number of elements in the input array. 

   array       on input, is an array containing some number of 
               elements in unspecified order. 
 

Detailed_Output

 
   array       on output, is the same array, with the elements 
               in re-ordered as specified by iorder. 

Parameters

 
   None. 
 

Exceptions

 
   1) If memory cannot be allocated to create a Fortran-style version of
      the input order vector, the error SPICE(MALLOCFAILED) is signaled.
 
   2) If ndim < 2, this routine executes a no-op.  This case is 
      not an error.

Files

 
   None. 
 

Particulars

 
   reordd_c uses a cyclical algorithm to re-order the elements of 
   the array in place. After re-ordering, element iorder[0] of 
   the input array is the first element of the output array, 
   element iorder[1] is the input array is the second element of 
   the output array, and so on. 

   The order vector used by reordd_c is typically created for 
   a related array by one of the order routines, as shown in 
   the example below. 
 

Examples

 
   In the following example, the ORDER and REORD routines are 
   used to sort four related arrays (containing the names, 
   masses, integer ID codes, and visual magnitudes for a group 
   of satellites). This is representative of the typical use of 
   these routines. 

      #include "SpiceUsr.h"
          .
          .
          .
      /.
      Sort the object arrays by name. 
      ./ 

      orderc_c ( namlen, names, n,  iorder ); 

      reordc_c ( iorder, n, namlen, names  );
      reordd_c ( iorder, n,         masses ); 
      reordi_c ( iorder, n,         codes  ); 
      reordd_c ( iorder, n,         vmags  );
 

Restrictions

 
   None. 
 

Literature_References

 
    None. 
 

Author_and_Institution

 
   N.J. Bachman    (JPL)
   W.L. Taber      (JPL) 
   I.M. Underwood  (JPL) 
 

Version

 
   -CSPICE Version 1.0.0, 11-JAN-2003 (EDW)

      Trivial. Corrected 'Detailed_output' section
      header to 'Detailed_Output'.

   -CSPICE Version 1.0.0, 10-JUL-2002 (NJB)

Index_Entries

 
   reorder a d.p. array 
 

Link to routine reordd_c source file reordd_c.c