Meridian.Builder.H3 (Meridian v0.1.0)

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Builds graphs from Uber H3 hexagonal grids.

Requires the optional :h3 dependency.

Topologies

  • :rook — the 6 edge-adjacent neighbors (default)
  • :queen — rook + 6 vertex-adjacent neighbors (12 total)

Examples

iex> graph =
...>   Meridian.Graph.new(kind: :undirected)
...>   |> Meridian.Builder.H3.grid(center: {40.7484, -73.9857}, resolution: 9, k_ring: 1)
iex> Meridian.Graph.node_count(graph)
7

Summary

Functions

grid(g, opts)

Creates a graph from an H3 hexagonal grid centered on a lat/lon point.

Functions

grid(g, opts)

@spec grid(
  Meridian.Graph.t(),
  keyword()
) :: Meridian.Graph.t()

Creates a graph from an H3 hexagonal grid centered on a lat/lon point.

Options

  • :center — {lat, lon} tuple (required)
  • :resolution — H3 resolution, 0–15 (required)
  • :k_ring — number of rings outward from center, default 1
  • :topology — :rook (default) or :queen
  • :node_data_fn — function (h3_index :: integer) -> map to populate node data

Examples

iex> graph =
...>   Meridian.Graph.new(kind: :undirected)
...>   |> Meridian.Builder.H3.grid(center: {37.7749, -122.4194}, resolution: 5, k_ring: 1)
iex> Meridian.Graph.node_count(graph) >= 1
true