人口密度を視覚化
変数バインディング式で、人口密度を計算および表示します。
<!DOCTYPE html><html><head><meta charset="utf-8"><title>人口密度を視覚化</title><meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no"><link href="https://api.mapbox.com/mapbox-gl-js/v2.14.1/mapbox-gl.css" rel="stylesheet"><script src="https://api.mapbox.com/mapbox-gl-js/v2.14.1/mapbox-gl.js"></script><style>body { margin: 0; padding: 0; }#map { position: absolute; top: 0; bottom: 0; width: 100%; }</style></head><body><div id="map"></div><script> // TO MAKE THE MAP APPEAR YOU MUST // ADD YOUR ACCESS TOKEN FROM // https://account.mapbox.com mapboxgl.accessToken = 'YOUR_MAPBOX_ACCESS_TOKEN';const map = new mapboxgl.Map({container: 'map', // container IDstyle: 'mapbox://styles/mapbox/streets-v11', // style URLcenter: [30.0222, -1.9596], // starting position [lng, lat]zoom: 7 // starting zoom}); map.on('load', () => {map.addSource('rwanda-provinces', {'type': 'geojson','data': 'https://docs.mapbox.com/mapbox-gl-js/assets/rwanda-provinces.geojson'});map.addLayer({'id': 'rwanda-provinces','type': 'fill','source': 'rwanda-provinces','layout': {},'paint': {'fill-color': ['let','density',['/', ['get', 'population'], ['get', 'sq-km']],['interpolate',['linear'],['zoom'],8,['interpolate',['linear'],['var', 'density'],274,['to-color', '#edf8e9'],1551,['to-color', '#006d2c']],10,['interpolate',['linear'],['var', 'density'],274,['to-color', '#eff3ff'],1551,['to-color', '#08519c']]]],'fill-opacity': 0.7}});});</script> </body></html>