This repository provides a simple script to generate TopoJSON files from the Madrid City Council's Statistics portal vector data.
In a browser (using d3-geo and Canvas):
<!DOCTYPE html>
<canvas width="960" height="600"></canvas>
<script src="https://d3js.org/d3.v5.min.js"></script>
<script src="https://d3js.org/topojson.v3.min.js"></script>
<script>
var context = d3.select("canvas").node().getContext("2d"),
path = d3.geoPath().context(context);
d3.json("https://unpkg.com/madrid-atlas@1.0.0/madrid/census_tracts.json", function(error, madrid) {
if (error) throw error;
context.beginPath();
path(topojson.mesh(madrid));
context.stroke();
});
</script>In Node (using d3-geo and node-canvas):
var fs = require("fs"),
d3 = require("d3-geo"),
topojson = require("topojson-client"),
Canvas = require("canvas"),
madrid = require("./node_modules/madrid-atlas/madrid/census_tracts.json");
var canvas = new Canvas(960, 600),
context = canvas.getContext("2d"),
path = d3.geoPath().context(context);
context.beginPath();
path(topojson.mesh(madrid));
context.stroke();
canvas.pngStream().pipe(fs.createWriteStream("preview.png"));Clone or download the repo, start a terminal and run npm install in the folder. This command will run the script and move the generated files to the mad folder.
If you need to make further adjustments (simplification, quantization) you can change the prepublish script and run npm install again.
# madrid/census_tracts.json <>
A preprojected TopoJSON (EPSG:3042) which contains five objects: census tracts, neighborhoods, districts and city. Every tract, neighborhood and district has its corresponding identifier, so it's easy to get started.
# madrid.objects.census_tracts
# madrid.objects.neighborhoods
# madrid.objects.districts
# madrid.objects.city
The original idea and implementation comes from Mike Bostock’s us-atlas and world-atlas.
Check out es-atlas and barcelona-atlas, which provide other Spanish administrative divisions with the same format.