d3_createSvg.js

//d3, a function return dom, but not handle a outside or global dom.
//refact: http://bl.ocks.org/mbostock/3885304
function type(d) {
  d.frequency = +d.frequency;
  return d;
}


function createSvg(data) {
   var margin = {top: 20, right: 20, bottom: 30, left: 40},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

var x = d3.scale.ordinal()
    .rangeRoundBands([0, width], .1);

var y = d3.scale.linear()
    .range([height, 0]);

var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom");

var yAxis = d3.svg.axis()
    .scale(y)
    .orient("left")
    .ticks(10, "%");
    
    
    var div = document.createElement("div");
    
    var svg  =  d3.select(div).append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");
    
    x.domain(data.map(function(d) { return d.letter; }));
  y.domain([0, d3.max(data, function(d) { return d.frequency; })]);

  svg.append("g")
      .attr("class", "x axis")
      .attr("transform", "translate(0," + height + ")")
      .call(xAxis);

  svg.append("g")
      .attr("class", "y axis")
      .call(yAxis)
    .append("text")
      .attr("transform", "rotate(-90)")
      .attr("y", 6)
      .attr("dy", ".71em")
      .style("text-anchor", "end")
      .text("Frequency");

  svg.selectAll(".bar")
      .data(data)
    .enter().append("rect")
      .attr("class", "bar")
      .attr("x", function(d) { return x(d.letter); })
      .attr("width", x.rangeBand())
      .attr("y", function(d) { return y(d.frequency); })
      .attr("height", function(d) { return height - y(d.frequency); });


    return div;
}
             
var datas = 
[
{"letter":"A","frequency":0.08167},
{"letter":"B","frequency":0.01492},
{"letter":"C","frequency":0.02782},
{"letter":"D","frequency":0.04253},
{"letter":"E","frequency":0.12702},
{"letter":"F","frequency":0.02288},
{"letter":"G","frequency":0.02015},
{"letter":"H","frequency":0.06094},
{"letter":"I","frequency":0.06966},
{"letter":"J","frequency":0.00153},
{"letter":"K","frequency":0.00772},
{"letter":"L","frequency":0.04025},
{"letter":"M","frequency":0.02406},
{"letter":"N","frequency":0.06749},
{"letter":"O","frequency":0.07507},
{"letter":"P","frequency":0.01929},
{"letter":"Q","frequency":0.00095},
{"letter":"R","frequency":0.05987},
{"letter":"S","frequency":0.06327},
{"letter":"T","frequency":0.09056},
{"letter":"U","frequency":0.02758},
{"letter":"V","frequency":0.00978},
{"letter":"W","frequency":0.02360},
{"letter":"X","frequency":0.00150},
{"letter":"Y","frequency":0.01974},
{"letter":"Z","frequency":0.00074}
];


document.body.innerHTML = createSvg(datas).innerHTML;