D3 code with variable

stat_graph.css

.graph {
  font: 10px sans-serif;
}
.axis path,
.axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}
.x.axis path {
  display: none;
}
.line {
  fill: none;
  stroke: steelblue;
  stroke-width: 2px;
}
.sparkcircle {
  fill: #f00;
  stroke: none;
}

stat_graph.html

{% extends 'oic/base.html' %}

{% load static %}

{% block statgraphcss %}
    <link rel="stylesheet" type="text/css" href="{% static 'oic/css/stat_graph.css' %}" />
{% endblock %}

{% block body_block %}

<!-- stat_graph.html -->

<div class="col-sm-8 col-sm-offset-2">

<h2>Graph of {{statname}}</h2>

<hr>

<span class="graph"></span>

<!-- statid is a number, like 1, 2, 3, etc.  -->  
<script>
var statid = {{statid}};
</script>

<script src="{% static 'oic/js/d3.v3.js' %}"></script>
<script src="{% static 'oic/js/stat_graph.js' %}"></script>

</div>

{% endblock %}

stat_graph.js

//function statgraph(statid) {

// had this hard-coded and worked just fine
// but with changes to HTML for "global" JS variable, no longer works and is "undefined"
// per the web site logs for the API call to get the data
// var statid = 1;

var margin = {top: 20, right: 20, bottom: 30, left: 50},
    width = 750 - margin.left - margin.right,
    height = 400 - margin.top - margin.bottom;
//var parseDate = d3.time.format("%Y-%m-%d").parse; // for dates like "2014-01-01"
//var parseDate = d3.time.format("%Y-%m-%dT00:00:00Z").parse;  // for dates like "2014-01-01T00:00:00Z"
var parseDate = d3.time.format("%Y-%m-%d").parse;  // for dates like "2014-01-01T00:00:00Z"
var x = d3.time.scale()
    .range([0, width]);
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");
var line = d3.svg.line()
    //.x(function(d) { return x(d.month); })
    .x(function(d) { return x(d.dt); })
    .y(function(d) { return y(d.value); });
var svg = d3.select(".graph").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 + ")");
//d3.json("{% url "play_count_by_month" %}", function(error, data) {
//d3.json("{% url "queue_count_by_month" %}", function(error, data) {
//d3.json("/oic/api/get_stat_values/1", function(error, data) {
d3.json("/oic/api/get_stat_values/"+statid, function(error, data) {
  data.forEach(function(d) {
    //d.month = parseDate(d.month);
    d.dt = parseDate(d.dt);
  });
  //x.domain(d3.extent(data, function(d) { return d.month; }));
  x.domain(d3.extent(data, function(d) { return d.dt; }));
  y.domain(d3.extent(data, function(d) { return d.value; }));
  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("Value");
  svg.append("path")
      .datum(data)
      .attr("class", "line")
      .attr("d", line);
  svg.selectAll(".dot")
    .data(data)
  .enter().append("circle")
      .attr("class", "sparkcircle")
      .attr("r", 2.5)
      .attr("cx", function(d) { return x(d.dt); })
      .attr("cy", function(d) { return y(d.value); });
});

//}