Download Gadm Data -version: 3.6-

# Example usage if __name__ == "__main__": # Download India data at admin level 1 (states) country = "IND" # India admin_level = 1 # States/Provinces gdf = download_gadm_data(country, version="3.6", level=admin_level) if gdf is not None: # Generate different feature types # 1. Generate boundary features boundaries = generate_feature(gdf, feature_type="boundary") print(f"Generated {len(boundaries['features'])} boundary features") # 2. Generate centroid features centroids = generate_feature(gdf, feature_type="centroid") print(f"Generated {len(centroids['features'])} centroid features") # 3. Generate simplified features (for web mapping) simplified = generate_feature(gdf, feature_type="simplified") print(f"Generated simplified features") # Save to GeoJSON import json with open(f"{country}_gadm36_level{admin_level}_boundaries.geojson", 'w') as f: json.dump(boundaries, f, indent=2) print("Saved boundaries to GeoJSON file") # Display first feature print("\nSample feature:") print(json.dumps(boundaries['features'][0], indent=2)[:500] + "...") import geopandas as gpd import os def download_gadm_alternative(country_code, level=0): """ Alternative method using direct download URLs """ # Alternative URLs for GADM 3.6 urls = { 'IND': 'https://geodata.ucdavis.edu/gadm/gadm3.6/gpkg/gadm36_IND_gpkg.zip', 'USA': 'https://geodata.ucdavis.edu/gadm/gadm3.6/gpkg/gadm36_USA_gpkg.zip', 'BRA': 'https://geodata.ucdavis.edu/gadm/gadm3.6/gpkg/gadm36_BRA_gpkg.zip', # Add more countries as needed }

def generate_feature(gdf, feature_type="boundary"): """ Generate a feature from the GADM data Parameters: - gdf: GeoDataFrame with GADM data - feature_type: Type of feature to generate ('boundary', 'centroid', 'bbox', or 'simplified') """ if gdf is None or len(gdf) == 0: print("No data available") return None features = [] for idx, row in gdf.iterrows(): feature = { "type": "Feature", "properties": {}, "geometry": None } # Add properties for col in gdf.columns: if col != 'geometry': feature["properties"][col] = str(row[col]) if row[col] is not None else None # Generate geometry based on feature_type if feature_type == "boundary": feature["geometry"] = row.geometry.__geo_interface__ elif feature_type == "centroid": centroid = row.geometry.centroid feature["geometry"] = centroid.__geo_interface__ feature["properties"]["feature_type"] = "centroid" elif feature_type == "bbox": bbox = row.geometry.bounds from shapely.geometry import box bbox_geom = box(*bbox) feature["geometry"] = bbox_geom.__geo_interface__ feature["properties"]["feature_type"] = "bounding_box" elif feature_type == "simplified": # Simplify geometry (reduce complexity) simplified = row.geometry.simplify(tolerance=0.01) feature["geometry"] = simplified.__geo_interface__ feature["properties"]["feature_type"] = "simplified" features.append(feature) # Create FeatureCollection feature_collection = { "type": "FeatureCollection", "features": features, "metadata": { "source": "GADM version 3.6", "feature_type": feature_type, "num_features": len(features) } } return feature_collection download gadm data -version 3.6-

zip_path = os.path.join(output_dir, f"gadm36_{country_code}.zip") # Example usage if __name__ == "__main__": #

with open(zip_path, 'wb') as f: for chunk in response.iter_content(chunk_size=8192): f.write(chunk) Generate simplified features (for web mapping) simplified =

import requests import zipfile

# Load the GeoPackage gpkg_path = os.path.join(output_dir, f"gadm36_{country_code}.gpkg") gdf = gpd.read_file(gpkg_path, layer=str(level))