grid: Grid Traversal

In h3o: H3 Geospatial Indexing System

Grid Traversal

Description

Functions used to traverse the H3 grid.

Usage

grid_disk(x, k = 1, safe = TRUE)

grid_ring(x, k = 1)

grid_distances(x, k = 1)

grid_path_cells(x, y)

grid_path_cells_size(x, y)

grid_distance(x, y)

grid_local_ij(x, y)

Arguments

x	an H3 vector.
k	the order of ring neighbors. 0 is the focal location (the observed H3 index). 1 is the immediate neighbors of the H3 index. 2 is the neighbors of the 1st order neighbors and so on.
safe	default TRUE. If FALSE uses the fast algorithm which can fail.
y	an H3 vector.

Details

• grid_disk(): returns the disk of cells for the identified K ring. It is a disk because it returns all cells to create a complete geometry without any holes. See grid_ring() if you do not want inclusive neighbors.

• grid_ring(): returns a K ring of neighbors around the H3 cell.

• grid_distances(): returns a list of numeric vectors indicating the network distances between neighbors in a K ring. The first element is always 0 as the travel distance to one's self is 0. If the H3 index is missing a 0 length vector will be returned.

• grid_path_cells(): returns a list of H3 vectors indicating the cells traversed to get from x to y. If either x or y are missing, an empty vector is returned.

• grid_path_cells_size(): returns an integer vector with the cell path distance between pairwise elements of x and y. If either x or y are missing the result is NA. grid_distance(): returns an integer vector with the network distance between pairwise elements of x and y. If either x or y are missing the result is NA. Effectively grid_path_cells_size() - 1.

• grid_local_ij() returns a two column data frame containing the columns i and j which correspond to the i,j coordinate directions to the destination cell.

Value

See details.

Examples

h3_strs <- c("841f91dffffffff", "841fb59ffffffff")
h3 <- h3_from_strings(h3_strs)

grid_disk(h3, 1)
grid_ring(h3, 2)
grid_distances(h3, 2)
grid_path_cells(h3, rev(h3))
grid_path_cells_size(h3, rev(h3))
grid_distance(h3, rev(h3))
grid_local_ij(h3, rev(h3))

h3o documentation built on Aug. 29, 2025, 5:34 p.m.