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Compact Hex Cells

Source: R/hex_compact.R
hex_compact.Rd

Merges child cells into their parent when all children are present. This is a lossless compression — no spatial information is lost. The compact representation uses fewer cells to cover the same area.

Usage

hex_compact(cell_ids, grid)

Arguments

cell_ids

Cell IDs to compact. For H3 grids, a character vector. For ISEA grids, a character vector of hierarchical index strings.

grid

A HexGridInfo object specifying the grid.

Value

A character vector of compacted cell IDs. Cells that could be merged into parents appear as parent IDs at coarser resolution.

Details

H3 backend: Uses the vendored H3 compactCells function.

ISEA backend (aperture 7, Z7 index): Groups cells by parent index (dropping the last digit). If all 7 children are present, replaces them with the parent. Iterates until no further compaction is possible.

See also

hex_uncompact() for the inverse operation, get_parent(), get_children() for hierarchical operations

Examples

# \donttest{
# H3 compaction
g <- hex_grid(resolution = 3, type = "h3")
parent <- "832830fffffffff"
children <- get_children(parent, g)[[1]]
compact <- hex_compact(children, g)
compact  # Should return the parent
# }