# coyote: CGSETDIFFERENCE

- coyote/Utilities
- [Source code]

Description

      This function is used to find the difference between two sets of integers.
      In other words, the function will find the values that are in Set A but
      are missing in Set B.

Categories

      Utilities

Returns

      A vector of values that are found in set_a but are missing in set_b.

Params

      set_a: in, required, type=integer
         A vector of integers.
      set_b: in, required, type=integer
         A vector of integers.

Keywords

      count: out, optional, type=integer
           This keyword contains the number of elements in the difference vector.
      noresult: in, optional
           Set this keyword to a value that will be returned from the function
           if no difference between the two sets of numbers is found. By default, set_a.
      positions: out, optional, type=integer
           An output keyword that will return the positions or locations in A of the values
           not found in B.
      success: out, optional, type=boolean
           This keyword is set to 1 if an difference was found, and to 0 otherwise.

Examples

      Here is how to use this program::
        IDL> set_a = [1,2,3,4,5]
        IDL> set_b = [4,5,6,7,8,9,10,11]
        IDL> Print, cgSetDifference(set_a, set_b)
            1  2  3

Author

      FANNING SOFTWARE CONSULTING::
         David W. Fanning
         1645 Sheely Drive
         Fort Collins, CO 80526 USA
         Phone: 970-221-0438
         E-mail: david@idlcoyote.com
         Coyote's Guide to IDL Programming: http://www.idlcoyote.com

History

      Change History::
         Written by: David W. Fanning, November 25, 2009, from code originally supplied to the IDL
            newsgroup by Research Systems software engineers.
         Added COUNT and POSITIONS keywords. Liam Steele, 13 Dec 2012.
         Defined values for COUNT and POSITIONS when there is no overlap in the vectors. 14 Dec 2012. LS.

Copyright

      Copyright (c) 2009-2013, Fanning Software Consulting, Inc.