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Abstract
I/O
Examples
Particulars
Required Reading
Version
Index_Entries

Abstract


   CSPICE_DSKZ02 returns plate model size parameters---plate count and
   vertex count---for a type 2 DSK segment.

I/O


   Given:

      handle    the handle of a DSK file containing a type 2
                segment from which data are to be fetched.

                [1,1] = size(handle); int32 = class(handle)

      dladsc    the DLA descriptor associated with the segment
                from which data are to be fetched.

                [SPICE_DLA_DSCSIZ,1]  = size(dladsc)
                                int32 = class(dladsc)

   the call:

      [nv, np] = cspice_dskz02( handle, dladsc )

   returns:

      nv        the number of vertices belonging to the specified plate
                model.

                [1,1] = size(nv); int32 = class(nv)

      np        the number of plates belonging to the specified plate
                model.

                [1,1] = size(np); int32 = class(np)

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.

   Look up all the vertices associated with each plate
   of the model contained in a specified type 2 segment. For each
   plate, display the plate's vertices and normal vector.

   For this example, we'll show the context of this look-up:
   opening the DSK file for read access, traversing a trivial,
   one-segment list to obtain the segment of interest.

      function dskz02_t( dsk )

         %
         % Declare DSK Mice parameters for use in API calls.
         %
         DSKMiceUser

         %
         % Constants
         %
         PBUFSIZ = 10000;

         %
         % Initial values
         %
         verts = zeros(3,3);

         %
         % Open the DSK file for read access.
         % We use the DAS-level interface for
         % this function.
         %
         handle  = cspice_dasopr( dsk );

         %
         % Begin a forward search through the
         % kernel, treating the file as a DLA.
         % In this example, it's a very short
         % search.
         %
         [dladsc, found] = cspice_dlabfs( handle );

         if ~found

            %
            % We arrive here only if the kernel
            % contains no segments. This is
            % unexpected, but we're prepared for it.
            %
            fprintf( 'No segments found in DSK file %s\n', dsk )
            return

         end

         %
         % If we made it this far, `dladsc' is the
         % DLA descriptor of the first segment.
         %
         % Get segment vertex and plate counts.
         %
         [nv, np] = cspice_dskz02( handle, dladsc );

         fprintf( '\n' )
         fprintf( 'Number of vertices:  %d\n', nv )
         fprintf( 'Number of plates:    %d\n', np )

         %
         %  Display the vertices of each plate.
         %
         remain = np;
         start  = 1;

         while (remain > 0 )

            %
            % `nread' is the number of plates we"ll read on this
            % loop pass. Set `nread' to the minimum of PBUFSIZ
            % and `remain'.
            %
            nread = min(PBUFSIZ, remain);

            plates = cspice_dskp02( handle, dladsc, start, nread );

            for  i = 1:(nread)

               plix = start + i - 1;

               %
               %  Read the vertices of the current plate.
               %
               for  j = 1:3

                  verts(j,:) = cspice_dskv02( handle, ...
                                              dladsc, plates(j,i), 1 );

               end


               %
               % Display the vertices of the ith plate:
               %
               fprintf( '\n' )
               fprintf( 'Plate number: %d\n', i )

               for  j = 1:3
                  fprintf( '   Vertex %d: ( %16.8e %16.8e %16.8e )\n', ...
                                                         j, verts(j,:) )
               end

               %
               % Display the normal vector of the current plate:
               %
               normal = cspice_dskn02( handle, dladsc, plix );
               fprintf( '   Normal:   ( %16.8e %16.8e %16.8e )\n', normal )

            end

            start  = start  + nread;
            remain = remain - nread;

         end

         %
         % Close file.
         %
         cspice_dascls( handle )

   MATLAB outputs:

      >> dskz02_t('solid.bds' )

      Number of vertices:  12
      Number of plates:    20

      Plate number: 1
         Vertex 1: (   0.00000000e+00   0.00000000e+00   1.17557000e+00 )
         Vertex 2: (   1.05146000e+00   0.00000000e+00   5.25731000e-01 )
         Vertex 3: (   3.24920000e-01   1.00000000e+00   5.25731000e-01 )
         Normal:   (   4.91124160e-01   3.56821347e-01   7.94654382e-01 )

      Plate number: 2
         Vertex 1: (   0.00000000e+00   0.00000000e+00   1.17557000e+00 )
         Vertex 2: (   3.24920000e-01   1.00000000e+00   5.25731000e-01 )
         Vertex 3: (  -8.50651000e-01   6.18034000e-01   5.25731000e-01 )
         Normal:   (  -1.87592328e-01   5.77350079e-01   7.94654645e-01 )

           ...

      Plate number: 19
         Vertex 1: (  -3.24920000e-01  -1.00000000e+00  -5.25731000e-01 )
         Vertex 2: (   0.00000000e+00   0.00000000e+00  -1.17557000e+00 )
         Vertex 3: (   8.50651000e-01  -6.18034000e-01  -5.25731000e-01 )
         Normal:   (   1.87592328e-01  -5.77350079e-01  -7.94654645e-01 )

      Plate number: 20
         Vertex 1: (   8.50651000e-01  -6.18034000e-01  -5.25731000e-01 )
         Vertex 2: (   0.00000000e+00   0.00000000e+00  -1.17557000e+00 )
         Vertex 3: (   8.50651000e-01   6.18034000e-01  -5.25731000e-01 )
         Normal:   (   6.07061680e-01   0.00000000e+00  -7.94654715e-01 )

Particulars


   This routine enables SPICE-based user applications to conveniently
   fetch the plate and vertex counts of a type 2 DSK segment.

   See the routine CSPICE_DSKB02 (DSK, fetch type 2 bookkeeping data)
   for an interface that returns all type 2 DSK segment bookkeeping
   data in a single call.

Required Reading


   For important details concerning this module's function, please
   refer to the CSPICE routine dskz02_c.

   MICE.REQ
   DAS.REQ
   DSK.REQ

Version


   -Mice Version 1.0.0, 07-MAY-2014, NJB (JPL), EDW (JPL)

Index_Entries


   fetch model size parameters from a type 2 dsk segment


Wed Apr  5 18:00:31 2017