rveciana - population-density-in-equatorial-guinea-using-geomercatorequatorialguinea-projection

Population density in Equatorial Guinea, using geoMercatorEquatorialGuinea projection

This block shows how to use the geoMercatorEquatorialGuinea projection from d3-composite-projections

Data source:

The color scale legend is created using d3-legend

<!DOCTYPE html>
<meta charset="utf-8">
<style>

.states {
  fill: #ccc;
  stroke: #fff;
}
</style>
<body>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script src="http://d3js.org/topojson.v1.min.js"></script>
<script src="https://unpkg.com/d3-composite-projections@1.2.0/d3-composite-projections.min.js"></script>
<script src="http://d3js.org/colorbrewer.v1.min.js"></script>
<script src="https://d3js.org/d3-scale-chromatic.v1.min.js"></script>

<script src="d3-legend.min.js"></script>

<script>
var width = 960,
    height = 500;

var popDensity = {"Annobón": 294.6, "Bioko Norte": 298.2, "Bioko Sur": 23.4, "Centro Sur": 12.7, "Kié-Ntem": 42.4, "Litoral": 44.8, "Wele-Nzas": 28.8};

var projection = d3.geoMercatorEquatorialGuinea();
var path = d3.geoPath()
    .projection(projection);

/*
var colorScale = d3.scaleOrdinal(colorbrewer.PuRd[9])
    .domain([0,50, 100, 150, 200, 250, 300]);*/

    var colorScale =  d3.scaleLinear()
       .domain([0, 300])
       .range(["rgb(46, 73, 123)", "rgb(71, 187, 94)"]);

colorScale = d3.scaleSequential(d3.interpolateYlOrRd)
        .domain([0, 300]);

console.info(colorScale(3));

var svg = d3.select("body").append("svg")
    .attr("width", width)
    .attr("height", height);

    var t = d3.transition();
d3.json("ge.json", function(error, ge) {
  var france = topojson.feature(ge, ge.objects.ge);
  svg.selectAll(".land")
      .data(france.features)
      .enter()
      .append("path")
      .attr("class", "land")
      .attr("d", path)
      .style("fill", function(d){console.info(colorScale(popDensity[d.properties.NAME_1])); return colorScale(popDensity[d.properties.NAME_1]);})
      .style("stroke", "#000")
      .style("stroke-width", "0.5px");

  svg
    .append("path")
      .style("fill","none")
      .style("stroke","#777")
      .attr("d", projection.getCompositionBorders());


    svg.append("g")
      .attr("class", "legendLinear")
      .attr("transform", "translate(700, 430)");

    var legendLinear = d3.legendColor()
      .labelFormat(d3.format(".0f"))
      .title("Densidad de población (hab./km2)")
      .shapeWidth(30)
      .orient('horizontal')
      .scale(colorScale);

    svg.select(".legendLinear")
      .call(legendLinear);

});

</script>