Oklahoma voting precincts

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<style>

body {
  margin: 0;
}

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<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script src="//d3js.org/topojson.v1.min.js"></script>
<script src="colorbrewer.js"></script>
<script>

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

var scale,
    translate,
    area; // minimum area threshold for simplification

var clip = d3.geo.clipExtent()
    .extent([[0, 0], [width, height]]);

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    .translate([0, 0])
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    .scaleExtent([1, 20]);

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var path = d3.geo.path()
    .projection({stream: function(s) { return simplify.stream(clip.stream(s)); }})
    .context(context);

d3.json("ok-precincts.json", function(error, ok) {
  if (error) throw error;

topojson.presimplify(ok);

var precincts = topojson.feature(ok, ok.objects.merged);
  var precinct_boundary = topojson.mesh(ok, ok.objects.merged, function(a, b) { return a !== b; });

canvas
      .call(zoom.on("zoom", zoomed))
      .call(zoom.event);

function zoomed() {
    translate = zoom.translate();
    scale = zoom.scale();
    area = 1 / scale / scale;

context.clearRect(0, 0, width, height);

context.save();

context.beginPath();
    path(precincts);
    context.fillStyle = '#3182bd';
    context.fill();

context.beginPath();
    path(precinct_boundary);
    context.strokeStyle = "#fff";
    context.lineWidth = .35;
    context.stroke();

context.restore();
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});

</script>

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