  is the ID of the first plate to be fetched from the
                  segment designated by `handle' and `dladsc'. The ID
                  of a plate is its ordinal position within the
                  segment. Plate IDs range from 1 to NP, where NP is
                  the number of plates in the segment.
 
                  Note that Fortran-style 1-based indexing is used for
                  plate IDs because these IDs must be consistent with
                  the IDs used in DSK files, across all l