Genome Browser

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  </style>
</head>

<body>
  <script>
    <!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  </style>
</head>

<body>
  <script>
    // Feel free to change or delete any of the code you see in this editor!
    var svg = d3.select("body").append("svg")
      .attr("width", 960)
      .attr("height", 500)
        
    
    var flag_data = [{"fill":"blue", "x": 100},
                {"fill":"white", "x": 300},
                {"fill":"red", "x": 500}]
    
    console.log(flag_data);
    
    svg.selectAll("rect") //selects anything in the svg data file
    	.data(flag_data)	//data join... what connects the data to making the pic
    	.enter()
    	.append("rect")
    	.attr("y",100)
    	.attr("x", function(d) {return d.x;})
    	.attr("width", 200)
    	.attr("height", 400)
    	.attr("fill", function (d) {return d.fill})

</script>
</body>

https://d3js.org/d3.v4.min.js