Convert cell ID to hierarchical index string

Advanced function for working with hierarchical index strings. Most users don't need this - use cell IDs directly.

Usage

cell_to_index(cell_id, grid)

Arguments

cell_id

Cell IDs: integer64 for ISEA grids (whole numbers below 2^53 and digit strings are accepted), character for H3 grids

grid

A HexGridInfo or HexData object

Value

Character vector of hierarchical index strings

Details

A cell ID numbers the cells of one resolution from 1, so it names a cell only together with its grid. The index string carries its resolution in its length and names one cell among all resolutions of the grid's family, and so serves as the zonal identifier of OGC Topic 21; an H3 index carries its resolution in its bits.