Scatter Plot w/Histogram Axes

Scatter plot with histogram axes in d3 v4. Based on this this Python example and coded for this stackoverflow question.

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

</style>
</head>

<body>
  <script src="//d3js.org/d3.v4.min.js"></script>
  <script>
    // set the dimensions and margins of the graph
    var margin = {
        top: 80,
        right: 80,
        bottom: 20,
        left: 20
      },
      width = 400 - margin.left - margin.right,
      height = 400 - margin.top - margin.bottom;

var svg = d3.select("body").append("svg")
      .attr("width", width + margin.left + margin.right)
      .attr("height", height + margin.top + margin.bottom)

var g = svg.append("g")
      .attr("transform",
        "translate(" + margin.left + "," + margin.top + ")");

var x = d3.scaleLinear().range([0, width]).domain([0, 10]),
      y = d3.scaleLinear().range([height, 0]).domain([0, 10]);

// Add the X Axis
    g.append("g")
      .attr("transform", "translate(0," + height + ")")
      .call(d3.axisBottom(x));

// Add the Y Axis
    g.append("g")
      .call(d3.axisLeft(y));

var random = d3.randomNormal(0, 1.2),
      data = d3.range(100).map(function() {
        return [random() + 5, random() + 5];
      });

g.selectAll(".point")
      .data(data)
      .enter()
      .append("circle")
      .attr("cx", function(d) {
        return x(d[0]);
      })
      .attr("cy", function(d) {
        return y(d[1]);
      })
      .attr("r", 7)
      .style("fill", "steelblue")
      .style("stroke", "lightgray");

// top histogram
    var gTop = svg.append("g")
      .attr("transform",
        "translate(" + margin.left + "," + 0 + ")");

var xBins = d3.histogram()
      .domain(x.domain())
      .thresholds(x.ticks(10))
      .value(function(d) {
        return d[0];
      })(data);

var xy = d3.scaleLinear()
      .domain([0, d3.max(xBins, function(d) {
        return d.length;
      })])
      .range([margin.top, 0]);

var xBar = gTop.selectAll(".bar")
      .data(xBins)
      .enter().append("g")
      .attr("class", "bar")
      .attr("transform", function(d) {
        return "translate(" + x(d.x0) + "," + xy(d.length) + ")";
      });

var bWidth = x(xBins[0].x1) - x(xBins[0].x0) - 1;
    xBar.append("rect")
      .attr("x", 1)
      .attr("width", bWidth)
      .attr("height", function(d) {
        return margin.top - xy(d.length);
      })
      .style("fill", "steelblue");

xBar.append("text")
      .attr("dy", ".75em")
      .attr("y", 2)
      .attr("x", bWidth / 2)
      .attr("text-anchor", "middle")
      .text(function(d) {
        return d.length < 4 ? "" : d.length;
      })
      .style("fill", "white")
      .style("font", "9px sans-serif");
      
    // right histogram
    var gRight = svg.append("g")
      .attr("transform",
        "translate(" + (margin.left + width) + "," + margin.top + ")");

var yBins = d3.histogram()
      .domain(y.domain())
      .thresholds(y.ticks(10))
      .value(function(d) {
        return d[1];
      })(data);

var yx = d3.scaleLinear()
      .domain([0, d3.max(yBins, function(d) {
        return d.length;
      })])
      .range([0, margin.right]);

var yBar = gRight.selectAll(".bar")
      .data(yBins)
      .enter().append("g")
      .attr("class", "bar")
      .attr("transform", function(d) {
        return "translate(" + 0 + "," + y(d.x1) + ")";
      });

var bWidth = y(yBins[0].x0) - y(yBins[0].x1) - 1;
    yBar.append("rect")
      .attr("y", 1)
      .attr("width", function(d){
        return yx(d.length);
      })
      .attr("height", bWidth)
      .style("fill", "steelblue");

yBar.append("text")
      .attr("dx", "-.75em")
      .attr("y", bWidth / 2 + 1)
      .attr("x", function(d){
        return yx(d.length);
      })
      .attr("text-anchor", "middle")
      .text(function(d) {
        return d.length < 4 ? "" : d.length;
      })
      .style("fill", "white")
      .style("font", "9px sans-serif");
      
  </script>
</body>

</html>

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