analyze_green_and_tree_count_density: Analyze Green Space or Tree Count Density with Research...

In greenR: Green Index Quantification, Analysis and Visualization

Analyze Green Space or Tree Count Density with Research Metrics and Lorenz Curve

Description

This function analyzes the spatial distribution of green spaces or trees using counts per hexagon, avoiding unreliable area estimates. It calculates inequality and distribution metrics and produces an interactive map, analytics, and optional Lorenz curve and JSON export. Automatically selects binning strategy if data are too sparse for quantile or Jenks categorization.

Usage

analyze_green_and_tree_count_density(
  osm_data,
  mode = c("green_area", "tree_density"),
  h3_res = 8,
  color_palette = c("#FFEDA0", "#74C476", "#005A32"),
  opacity = 0.7,
  tile_provider = c("OpenStreetMap", "Positron", "DarkMatter", "Esri.WorldImagery"),
  enable_hover = TRUE,
  categorization_method = c("quantile", "jenks", "fixed"),
  fixed_breaks = NULL,
  save_html = FALSE,
  html_map_path = "density_map.html",
  save_json = FALSE,
  json_file = "density_data.json",
  save_lorenz = FALSE,
  lorenz_plot_path = "lorenz_curve.png"
)

Arguments

osm_data	Output from get_osm_data(), containing at least osm_data$green_areas$osm_polygons or osm_data$trees$osm_points.
mode	Character. Either "green_area" (green polygon count) or "tree_density" (point count). Default: "green_area".
h3_res	Integer. H3 resolution (0–15). Default = 8.
color_palette	Character vector of 3 colors for choropleth. Default = c("#FFEDA0", "#74C476", "#005A32").
opacity	Numeric. Fill opacity for hexes. Default = 0.7.
tile_provider	Character. One of c("OpenStreetMap", "Positron", "DarkMatter", "Esri.WorldImagery"). Default = "OpenStreetMap".
enable_hover	Logical. Show hover labels. Default = TRUE.
categorization_method	Character. One of c("quantile", "jenks", "fixed"). Default = "quantile".
fixed_breaks	Numeric vector of length 2. Thresholds for "fixed" method. Default = NULL.
save_html	Logical. Save map as self-contained HTML. Default = FALSE.
html_map_path	Character. Filepath for HTML. Default = "density_map.html".
save_json	Logical. Save hex centroid + value JSON. Default = FALSE.
json_file	Character. Filepath for JSON. Default = "density_data.json".
save_lorenz	Logical. Save Lorenz curve PNG. Default = FALSE.
lorenz_plot_path	Character. Filepath for Lorenz PNG. Default = "lorenz_curve.png".

Value

A list with:

map	Leaflet map object
analytics	Named list of summary statistics
json_file	Path to JSON file (if saved)
lorenz_plot	Path to Lorenz PNG (if saved)

Examples

## Not run: 
# Example: green area polygons (default mode)
osm_data <- get_osm_data("Zurich, Switzerland", features = c("green_areas", "trees"))
result <- analyze_green_and_tree_count_density(
  osm_data = osm_data,
  mode = "green_area",
  h3_res = 8,
  save_lorenz = TRUE
)
print(result$analytics)
result$map
result$lorenz_plot

# Example: tree density
result2 <- analyze_green_and_tree_count_density(
  osm_data = osm_data,
  mode = "tree_density",
  h3_res = 8,
  color_palette = c("#F0E442", "#009E73", "#D55E00"),
  save_html = TRUE
)
result2$map

## End(Not run)

greenR documentation built on Nov. 30, 2025, 5:06 p.m.