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mcf_st_cell_find_next — Get the next non-empty sparse-table cell
subroutine mcf_st_cell_find_next(dsid,row_index,column_index,next) integer*4 dsid integer*8 row_index integer*8 column_index integer*8 next
mcf_st_cell_find_next attempts to find,
for the sparse-table dataset identified by dsid,
the next non-empty cell, relative to the non-empty cell identified
by the row index row_index and the column index
column_index.
Using mcf_st_cell_find_next, one can
efficiently iterate over all non-empty cells of a row.
Cells are in general not sorted inside a row (see mcf_st_row_sort). For
unsorted rows, the column indices returned by
mcf_st_cell_find_next are in the order by which
the cells were added to the row.
dsid (input)Dataset identifier.
row_index (input)Row index, starting at 1.
column_index (input)Index of the column whose next non-empty cell is requested. Column indices start at 1. The column index must either be 0 or refer to a non-empty cell. If 0 is given, the first non-empty cell is requested.
next (output)If no error occurred and the next non-empty cell exists, the column index of the next non-empty cell is returned (starting from 1). If such a cell does not exist, 0 is returned. If an error occurred, a negative value indicating the MemCom error number is returned.