Procedure

   SpiceBoolean isordv_c ( ConstSpiceInt  * array,
                           SpiceInt         n      ) 

Abstract

 
   Determine whether an array of n items contains the integers 
   0 through n-1. 
 

Required_Reading

 
   None. 
 

Keywords

 
   SEARCH 
   SORT 
   UTILITY 
 

Brief_I/O

 
   Variable  I/O  Description 
   --------  ---  -------------------------------------------------- 
   array      I   Array of integers. 
   n          I   Number of integers in array. 
 
   The function returns SPICETRUE if the array contains the integers 
   0 through n-1, otherwise it returns SPICEFALSE. 
 

Detailed_Input

 
   array      is an array of integers.  Often this will be an array 
              that is a candidate order vector to be passed to 
              a routine for re-ordering some parallel array. 
 
   n          is the number of elements in array. 
 

Detailed_Output

 
   The function returns SPICETRUE if the array contains the integers 
   1 through n.  Otherwise it returns SPICEFALSE. 
 

Parameters

 
   None. 
 

Exceptions

  
   1) If n < 1, the function returns SPICEFALSE.

   2) If memory is not available to create a local copy of the order
      vector, the error SPICE(MALLOCFAILED) is signaled.
 

Files

 
   None. 
 

Particulars

 
   This function provides a simple means of determining whether 
   or not an array of n integers contains exactly the integers 
   0 through n-1.  An array with this property is called an
   "order vector."  Order vectors are returned by the CSPICE
   routines

      orderc_c
      orderd_c
      orderi_c

   and are accepted as input by the CSPICE routines

      reordc_c
      reordd_c
      reordi_c
      reordl_c
 

Examples

 
   1) Suppose you wished to reorder an array of strings based upon 
      a ranking array supplied by a user.  If the ranking array 
      contains any duplicates or refers to indices that are out 
      of the range of valid indices for the array of strings, 
      the attempt to reorder the array of strings cannot succeed. 
      Its usually better to detect such a possibility before 
      you begin trying to reorder the array of strings.  This routine 
      will detect the error. 
 
      The code fragment below illustrates this idea. 
 
         #include "SpiceUsr.h"
                  . 
                  . 
                  . 
           
         if ( isordv_c ( ordvec, n ) )  
         {
            ...reorder the input array of strings 
 
            reordc_c ( ordvec, n, lenvals, strings );
         }
         else 
         { 
            ...state the problem and let the user decide what 
            to do about it. 
                  . 
                  . 
                  . 
         } 
  

Restrictions

 
   None. 
 

Literature_References

 
   None. 
 

Author_and_Institution

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

Version

 
   -CSPICE Version 1.1.0, 16-FEB-2005 (NJB)  

      Bug fix:  dynamic memory is now freed.

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

Index_Entries

 
   test whether an integer array is an order vector 
 

Link to routine isordv_c source file isordv_c.c