D3 Force Simulation

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

<body>
  <h1>Force Directed layout</h1>
  <svg 
    width=800 
    height=400
    id="network"></svg>
  
    <script src="https://d3js.org/d3.v4.min.js"></script>
  <script>
    // Copy drag from: https://bl.ocks.org/mbostock/4062045
    
    let svg = d3.select("#network"),
        width = +svg.attr("width"),
        height = + svg.attr("height"),
        N = 100,
        r = d3.scaleSqrt()
    			.domain([0, 50])
    			.range([1, 15]),
        x = d3.scaleBand()
    			.domain(["M", "F"])
    			.range([50, width-50]),
        c = d3.scaleOrdinal()
    			.domain(["M", "F"])
    			.range(["steelblue", "firebrick"]),
        y = d3.scaleLinear()
    			.domain([20, 50])
    			.range([height, 0]),
        g = svg.append("g")
    			.attr("class", "graph"),
        tooltip = svg.append("text");
    
    let nodes = [
      {name:"John", age:23, gender:"M"},
      {name:"Edwin", age:25, gender:"M"},
      {name:"Santi", age:25, gender:"M"},
      {name:"Eliza", age:22, gender:"F"},      
      {name:"Magda", age:32, gender:"F"},            
      {name:"Vicente", age:43, gender:"M"},                  
      {name:"Sonia", age:44, gender:"F"}                            
    ]
    
    let links = [
      {source:"John", target:"Vicente", weigth:3},
      {source:"Edwin", target:"Vicente"},
      {source:"Santi", target:"Edwin"},
      {source:"Eliza", target:"Vicente"},
      {source:"Magda", target:"Vicente"},      
      {source:"John", target:"Sonia"},
      {source:"Edwin", target:"Sonia"},
      {source:"Eliza", target:"Sonia"},
      
    ]
    console.log(width, height);
    
    let simulation = d3.forceSimulation(nodes)
    	.force("x", d3.forceX((d) => x(d.gender))
           .strength(0.3))
    	.force("y", d3.forceY((d) => y(d.age))
            .strength(0.5))    
//     	.force("charge", d3.forceManyBody().strength(-50))
    	.force("collide", d3.forceCollide(d => r(d.age) + 1))
    	.force("link", d3.forceLink(links)
            	.id((d) => d.name)
             .distance(10).strength(0.1))
    
    	.on("tick", ticked);
    	
    
    console.log("nodes", nodes);
    console.log("links", links);    
    
    
    let sellinks = g.selectAll(".link")
    	.data(links)
    	.enter()
    	.append("line")
    	.attr("class", "link")
      .style("stroke", "#aaa")
    	.style("stroke-width", "10px")
      .style("opacity", 0.9)
    
    let selnodes = g.selectAll(".node")
    	.data(nodes)
    	.enter()
    	.append("circle")
    	.attr("class", "node")
      .style("fill", d => c(d.gender))
      .attr("r", d => r(d.age))
    	.on("mouseover", (d) => {
        tooltip.text(d.name)
        	.transition()
        	.duration(1000)
        	.attr("x", d.x)
        	.attr("y", d.y - 20);        
        
        console.log("clicked!", d);
      })
      .call(d3.drag()
            .on("start", dragstarted)
            .on("drag", dragged)
            .on("end", dragended));

selnodes.append("title")
    	.text(d => d.name);

function ticked() {
			sellinks.attr("x1", (l) => l.source.x)
        .attr("y1", (l) => l.source.y)
        .attr("x2", (l) => l.target.x)
        .attr("y2", (l) => l.target.y);

selnodes.attr("cx", (d) => d.x)
	      .attr("cy", (d) => d.y);
   }// ticked
    
function dragstarted(d) {
  if (!d3.event.active) simulation.alphaTarget(0.3).restart();
  d.fx = d.x;
  d.fy = d.y;
}

function dragged(d) {
  d.fx = d3.event.x;
  d.fy = d3.event.y;
}

function dragended(d) {
  if (!d3.event.active) simulation.alphaTarget(0);
  d.fx = null;
  d.fy = null;
}

</script>
</body>

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