Log Axis with Zero by mbostock

You might reserve a special place to render zeroes when using a log axis, since normally these will be displayed at infinity. However, since this represents a discontinuity in the encoding, it’s important to show the discontinuity visually.

index.html

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

.axis text {
  font: 10px sans-serif;
}

.axis path,
.axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}

</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>

var margin = {top: 210, right: 20, bottom: 220, left: 60},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

var x = d3.scale.log()
    .domain([1e-1, 1e4])
    .range([0, width]);

var x0 = d3.scale.ordinal()
    .domain([0])
    .range([-30]);

var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom")
    .ticks(20, d3.format(",.1s"));

var x0Axis = d3.svg.axis()
    .scale(x0)
    .orient("bottom");

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

svg.append("g")
    .attr("class", "x axis")
    .call(xAxis);

svg.append("g")
    .attr("class", "x-zero axis")
    .call(x0Axis);

</script>