d3.js - 需要帮助调试Chrome，Safari和Firefox中的差异

Question

I am experimenting with this d3 demo and I am having trouble debugging why I am experiencing different behavior in Chrome vs. Safari/FireFox. If I run the full code below, it works in Chrome but not in Safari/Firefox. I seem to have isolated the problem to the following:

If I change this line:

var circles = chart.select("#points").selectAll("circle")

to this:

var circles = chart.selectAll("circle")

it works in Safari/Firefox/Chrome, but I want to understand what is happening and why the code below doesn't work. Any insight would be greatly appreciated.

Full Code

 <svg>
  <g id="chart">
   <g id="bg">
   </g>
   <g id="countries">
   </g>
   <g id="points">
   </g>
  </g>
 </svg>


  <script type="text/javascript">

  d3.json("costofliving.json", function(col) {

    var cx = 200;
    var cy = 132;

    var cw = 400;
    var ch = 400;

    var svg = d3.select("svg");
    var nticks = 14;

    var price_min = 0;
    var price_max = d3.max(col, function(d) {return d.price});

    var rent_min = 0;
    var rent_max = d3.max(col, function(d) {return d.rent});

    var price_scale = d3.scale.linear()
      .domain([price_min, price_max])
      .range([ch, 0]);
    var rent_scale = d3.scale.linear()
      .domain([rent_min, rent_max])
      .range([0, cw]);

    var price_layout = d3.layout.histogram()
      .value(function(d) { return d.price })
      .range([0, price_max])
      .bins(nticks);

    var rent_layout = d3.layout.histogram()
     .value(function(d) { return d.rent })
     .range([0, rent_max])
     .bins(nticks);

   var chart = svg.append("g")
    .attr("transform", "translate(" + [cx, cy] + ")");

  chart.append("g")
   .attr("id", "countries")
   .style("opacity", 0);

  chart.append("g")
   .attr("id", "points")

  var circles = chart.select("#points").selectAll("circle")
   .data(col);

  circles.enter()
   .append("circle")

  circles.attr({
    r: 6,
    cx: function(d,i) {
    return rent_scale(d.rent);
   },
    cy: function(d,i) {
    return price_scale(d.price);
   }
  })  
 });
 </script>

Answer 1

You need to set a width and height for any svg element in Firefox. According to the W3C Spec , the svg element will use "100%" as default, but my Firefox 17 (and probably other browsers) may not yet implement it like that.

When setting some absolute values in your code it works as expected.

<svg width="600" height="600">