Abstract

   CSPICE_WNFLTD filters (removes) small intervals from a
   double precision window.

I/O

   Given:

      smlint   scalar limiting measure of the small intervals to be
               filtered. Intervals of measure less than or equal to
                `smlint' are removed from the window.

               [1,1] = size(smlint); double = class(smlint)

      window_i SPICE window containing zero or more intervals.

               [2m,1] = size(window_i); double = class(window_i)

   the call:

      [window_f] = cspice_wnfltd( smlint, window_i )

   returns:

      window_f SPICE window containing zero or more intervals representing
               the original `window_i', after `smlint' intervals have been
               removed.

               [2n,1] = size(window_f); double = class(window_f)

Parameters

   None.

Examples

   Any numerical results shown for this example may differ between
   platforms as the results depend on the SPICE kernels used as input
   and the machine specific arithmetic implementation.

   1) Given a double precision window, containing the following four
      intervals:

         [ 1.0, 3.0 ], [ 7.0, 11.0 ], [ 23.0, 27.0 ], [ 29.0, 29.0 ]

      remove any intervals smaller than or equal to 0.0. From the
      resulting window, remove any intervals smaller than or equal to
      2.0; then those of measures less than or equal to 3; and,
      finally, those smaller than or equal to 4.0.

      Example code begins here.


      function wnfltd_ex1()

         %
         % Let `window' contain the intervals
         %
         window = [ [ 1; 3 ]; [ 7; 11 ]; [ 23; 27 ]; [ 29; 29 ]; ];

         %
         % Apply the following series of calls
         %
         window = cspice_wnfltd(  0, window );
         fprintf( '1: Removing intervals smaller than or equal to 0.0\n' );
         for i=1:cspice_wncard(window)

            [left, right] = cspice_wnfetd( window, i );
            fprintf( '%16.6f %16.6f\n', left, right  );

         end

         window = cspice_wnfltd(  2, window );
         fprintf( '2: Removing intervals smaller than or equal to 2.0\n' );
         for i=1:cspice_wncard(window)

            [left, right] = cspice_wnfetd( window, i );
            fprintf( '%16.6f %16.6f\n', left, right  );

         end

         window = cspice_wnfltd(  3, window );
         fprintf( '3: Removing intervals smaller than or equal to 3.0\n' );
         for i=1:cspice_wncard(window)

            [left, right] = cspice_wnfetd( window, i );
            fprintf( '%16.6f %16.6f\n', left, right  );

         end

         window = cspice_wnfltd(  4, window );
         fprintf( '4: Removing intervals smaller than or equal to 4.0\n' );
         for i=1:cspice_wncard(window)

            [left, right] = cspice_wnfetd( window, i );
            fprintf( '%16.6f %16.6f\n', left, right  );

         end


      When this program was executed on a Mac/Intel/Octave6.x/64-bit
      platform, the output was:


      1: Removing intervals smaller than or equal to 0.0
              1.000000         3.000000
              7.000000        11.000000
             23.000000        27.000000
      2: Removing intervals smaller than or equal to 2.0
              7.000000        11.000000
             23.000000        27.000000
      3: Removing intervals smaller than or equal to 3.0
              7.000000        11.000000
             23.000000        27.000000
      4: Removing intervals smaller than or equal to 4.0


      Note that the last result (4) represents an empty set.

Particulars

   This routine removes from the input window every interval with
   measure less than or equal to the limiting measure `smlint'.

Exceptions

   1)  The cardinality of the input `window_i' must be even. Left
       endpoints of stored intervals must be strictly greater than
       preceding right endpoints. Right endpoints must be greater
       than or equal to corresponding left endpoints. Invalid window
       data are not diagnosed by this routine and may lead to
       unpredictable results.

   2)  If `smlint' is less than or equal to zero, this routine has
       no effect on the window.

   3)  If any of the input arguments, `smlint' or `window_i', is
       undefined, an error is signaled by the Matlab error handling
       system.

   4)  If any of the input arguments, `smlint' or `window_i', is not
       of the expected type, or it does not have the expected
       dimensions and size, an error is signaled by the Mice
       interface.

Files

   None.

Restrictions

   None.

Required_Reading

   MICE.REQ
   WINDOWS.REQ

Literature_References

   None.

Author_and_Institution

   J. Diaz del Rio     (ODC Space)
   E.D. Wright         (JPL)

Version

   -Mice Version 1.1.0, 10-AUG-2021 (EDW) (JDR)

       Changed argument names "window" and "sml" to "window_i" and
       "smlint" for consistency with other routines.

       Edited the header to comply with NAIF standard. Added
       example's problem statement and reformatted example's output.

       Added -Parameters, -Exceptions, -Files, -Restrictions,
       -Literature_References and -Author_and_Institution sections, and
       completed -Particulars section.

       Eliminated use of "lasterror" in rethrow.

       Removed reference to the function's corresponding CSPICE header from
       -Required_Reading section.

   -Mice Version 1.0.1, 11-JUN-2013 (EDW)

       -I/O descriptions edits to conform to Mice documentation format.

   -Mice Version 1.0.0, 24-JUL-2007 (EDW)

Index_Entries

   filter small intervals from a d.p. window