bubble update

<html>
  <head>
    <p>click to update</p>
    <style>
    body {
      margin: 0;
      font-family: "Helvetica", sans-serif;
    }
    text {
      text-anchor: middle;
      fill: #fff;
    }
    </style>
  </head>
  <body>
    <script src="https://d3js.org/d3.v4.min.js"></script>
    <script src="https://unpkg.com/jeezy@1.11.2/lib/jeezy.min.js"></script>
    <script>
    var alphabet = "abcdefghijklmnopqrstuvwxyz".split("");

var width = window.innerWidth, height = window.innerHeight;

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

var pack = d3.pack()
        .size([width, height])
        .padding(1.5);
      
    var data = [{"name":"campus", "size":10},
                {"name":"atlanta", "size":8},
                {"name":"havana", "size":6},
                {"name":"oh", "size":2},
               ];

redraw(data);
      
    d3.select("p")
      .on("click", function() {
      var data1= [{"name":"campus", "size":1},
                {"name":"atlanta", "size":1},
                {"name":"havana", "size":1},
                {"name":"oh", "size":1},
               ];

redraw(data1);
    });

function redraw(classes){

// transition
      var t = d3.transition()
          .duration(750);

// hierarchy
      var h = d3.hierarchy({children: classes})
          .sum(function(d) { return d.size; })

//JOIN
      var circle = svg.selectAll("circle")
          .data(pack(h).leaves(), function(d){ return d.data.name; });

var text = svg.selectAll("text")
          .data(pack(h).leaves(), function(d){ return d.data.name; });

//EXIT
      circle.exit()
          .style("fill", "#b26745")
        .transition(t)
          .attr("r", 1e-6)
          .remove();

text.exit()
        .transition(t)
          .attr("opacity", 1e-6)
          .remove();

//UPDATE
      circle
        .transition(t)
          .style("fill", "#3a403d")
          .attr("r", function(d){ return d.r })
          .attr("cx", function(d){ return d.x; })
          .attr("cy", function(d){ return d.y; })

text
        .transition(t)
          .attr("x", function(d){ return d.x; })
          .attr("y", function(d){ return d.y; });

//ENTER
      circle.enter().append("circle")
          .attr("r", 1e-6)
          .attr("cx", function(d){ return d.x; })
          .attr("cy", function(d){ return d.y; })
          .style("fill", "#fff")
        .transition(t)
          .style("fill", "#45b29d")
          .attr("r", function(d){ return d.r });

text.enter().append("text")
          .attr("opacity", 1e-6)
          .attr("x", function(d){ return d.x; })
          .attr("y", function(d){ return d.y; })
          .text(function(d){ return d.data.name; })
        .transition(t)
          .attr("opacity", 1);
    }

</script>
  </body>
</html>

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

https://unpkg.com/jeezy@1.11.2/lib/jeezy.min.js