Index of Functions: A B C D E F G H I J K L M N O P Q R S T U V W X
Index Page wnfild_c
Table of contents
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
       wnfild_c ( Fill small gaps in a DP window )

       void wnfild_c ( SpiceDouble     smlgap,
                       SpiceCell     * window )
#### Abstract
       Fill small gaps between adjacent intervals of a double precision
       window.
#### Required_Reading
       WINDOWS
#### Keywords
       WINDOWS
#### Brief_I/O
       VARIABLE  I/O  DESCRIPTION
       --------  ---  --------------------------------------------------
       smlgap     I   Limiting measure of small gaps.
       window    I-O  Window to be filled.
#### Detailed_Input
       smlgap      is the limiting measure of the small gaps to be filled.
                   Adjacent intervals separated by gaps of measure less than
                   or equal to `smlgap' are merged. The measure `smlgap' is
                   signed, and is used as is---the absolute value of `smlgap'
                   is not used for in place of negative input values.

       window      on input, is a window containing zero or more
                   intervals.

                   `window' must be declared as a double precision SpiceCell.

                   CSPICE provides the following macro, which declares and
                   initializes the cell

                      SPICEDOUBLE_CELL        ( window, WINDOWSZ );

                   where WINDOWSZ is the maximum capacity of `window'.
#### Detailed_Output
       window      on output, is the original window, after adjacent
                   intervals separated by small gaps have been merged.
#### Parameters
       None.
#### Exceptions
       1)  The cardinality of the input `window' 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 `smlgap' is less than or equal to zero, this routine has
           no effect on the window.

       3)  If the `window' cell argument has a type other than
           SpiceDouble, the error SPICE(TYPEMISMATCH) is signaled.
#### Files
       None.
#### Particulars
       This routine removes small gaps between adjacent intervals
       by merging intervals separated by gaps of measure less than
       or equal to the limiting measure `smlgap'.
#### Examples
       The numerical results shown for these examples may differ across
       platforms. The results depend on the SPICE kernels used as input,
       the compiler and supporting libraries, 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 ]

          merge any adjacent intervals separated by a gap equal to or less
          than 3.0.

          Example code begins here.

          /.
             Program wnfild_ex1
          ./
          #include <stdio.h>
          #include "SpiceUsr.h"

          int main()
          {

             /.
             Local parameters.
             ./
             #define WNSIZE           10

             /.
             Local variables.
             ./
             SpiceDouble              left;
             SpiceDouble              right;

             SPICEDOUBLE_CELL ( window,  WNSIZE );

             SpiceInt                 i;

             /.
             Validate the window with size WNSIZE and zero elements.
             ./
             wnvald_c ( WNSIZE, 0, &window );

             /.
             Insert the intervals

                [ 1, 3 ]  [ 7, 11 ]  [ 23, 27 ]  [ 29, 29 ]

             into `window'.
             ./
             wninsd_c (  1.0,   3.0, &window );
             wninsd_c (  7.0,  11.0, &window );
             wninsd_c ( 23.0,  27.0, &window );
             wninsd_c ( 29.0,  29.0, &window );

             /.
             Loop over the number of intervals in `window', output
             the `left' and `right' endpoints for each interval.
             ./
             printf( "Initial window:\n" );
             for ( i=0; i<wncard_c(&window); i++)
             {
                wnfetd_c( &window, i, &left, &right );
                printf("   Interval %d [%8.3f, %8.3f]\n", i, left, right );
             }

             /.
             Fill the gaps smaller than or equal to 3.0
             ./
             wnfild_c ( 3.0, &window );

             /.
             Output the intervals.
             ./
             printf( "\nWindow after filling gaps <= 3.0:\n" );
             for ( i=0; i<wncard_c(&window); i++)
             {
                wnfetd_c( &window, i, &left, &right );
                printf("   Interval %d [%8.3f, %8.3f]\n", i, left, right );
             }

             return ( 0 );
          }

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

          Initial window:
             Interval 0 [   1.000,    3.000]
             Interval 1 [   7.000,   11.000]
             Interval 2 [  23.000,   27.000]
             Interval 3 [  29.000,   29.000]

          Window after filling gaps <= 3.0:
             Interval 0 [   1.000,    3.000]
             Interval 1 [   7.000,   11.000]
             Interval 2 [  23.000,   29.000]

       2) Using the same window from the first example:

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

          Then the following series of calls

             wnfild_c (  1.0, &window );                             (1)
             wnfild_c (  2.0, &window );                             (2)
             wnfild_c (  3.0, &window );                             (3)
             wnfild_c ( 12.0, &window );                             (4)

          produces the following series of windows

             [1.0,  3.0]  [7.0, 11.0]  [23.0, 27.0]  [29.0, 29.0]    (1)
             [1.0,  3.0]  [7.0, 11.0]  [23.0, 29.0]                  (2)
             [1.0,  3.0]  [7.0, 11.0]  [23.0, 29.0]                  (3)
             [1.0, 29.0]                                             (4)
#### Restrictions
       None.
#### Literature_References
       None.
#### Author_and_Institution
       N.J. Bachman        (JPL)
       J. Diaz del Rio     (ODC Space)
       H.A. Neilan         (JPL)
       W.L. Taber          (JPL)
       I.M. Underwood      (JPL)
       E.D. Wright         (JPL)
#### Version
       -CSPICE Version 1.1.0, 10-AUG-2021 (JDR)

           Changed input argument name "small" to "smlgap" for consistency
           with other routines.

           Edited the header to comply with NAIF standard. Added complete code
           example based on existing example.

           Extended description of argument "window" in -Detailed_Input to include
           type and preferred declaration method.

           Added entry #1 in -Exceptions section.

       -CSPICE Version 1.0.1, 27-JUL-2007 (EDW)

           Changed gap size in -Examples (4) from 10 to 12 to correct
           erroneous example.

       -CSPICE Version 1.0.0, 29-JUL-2002 (NJB) (HAN) (WLT) (IMU)
#### Index_Entries
       fill small gaps in a d.p. window
#### Link to routine wnfild_c source file wnfild_c.c

    Fri Dec 31 18:41:15 2021