ashtonburg/README.md

## README.md

      
    Raw
  

              README.md
            
          
    A variant of the simple bar chart using d3-scale and d3-request to render to Canvas.
forked from mbostock's block: Canvas Bar Chart

  
## data.tsv

          
            letter
            frequency

            
              A
              .08167

            
              B
              .01492

            
              C
              .02782

            
              D
              .04253

            
              E
              .12702

            
              F
              .02288

            
              G
              .02015

            
              H
              .06094

            
              I
              .06966

            
              J
              .00153

            
              K
              .00772

            
              L
              .04025

            
              M
              .02406

            
              N
              .06749

            
              O
              .07507

            
              P
              .01929

            
              Q
              .00095

            
              R
              .05987

            
              S
              .06327

            
              T
              .09056

            
              U
              .02758

            
              V
              .00978

            
              W
              .02360

            
              X
              .00150

            
              Y
              .01974

            
              Z
              .00074

## index.html
<!DOCTYPE html>
<meta charset="utf-8">
<canvas width="960" height="500"></canvas>
<script src="//d3js.org/d3.v4.0.0-alpha.4.min.js"></script>
<script>

var canvas = document.querySelector("canvas"),
    context = canvas.getContext("2d");

var margin = {top: 20, right: 20, bottom: 30, left: 40},
    width = canvas.width - margin.left - margin.right,
    height = canvas.height - margin.top - margin.bottom;

var x = d3.scaleBand()
    .rangeRound([0, width])
    .padding(0.1);

var y = d3.scaleLinear()
    .rangeRound([height, 0]);

context.translate(margin.left, margin.top);

d3.requestTsv("data.tsv", function(d) {
  d.frequency = +d.frequency;
  return d;
}, function(error, data) {
  if (error) throw error;

  x.domain(data.map(function(d) { return d.letter; }));
  y.domain([0, d3.max(data, function(d) { return d.frequency; })]);

  var yTickCount = 10,
      yTicks = y.ticks(yTickCount),
      yTickFormat = y.tickFormat(yTickCount, "%");

  context.beginPath();
  x.domain().forEach(function(d) {
    context.moveTo(x(d) + x.bandwidth() / 2, height);
    context.lineTo(x(d) + x.bandwidth() / 2, height + 6);
  });
  context.strokeStyle = "black";
  context.stroke();

  context.textAlign = "center";
  context.textBaseline = "top";
  x.domain().forEach(function(d) {
    context.fillText(d, x(d) + x.bandwidth() / 2, height + 6);
  });

  context.beginPath();
  yTicks.forEach(function(d) {
    context.moveTo(0, y(d) + 0.5);
    context.lineTo(-6, y(d) + 0.5);
  });
  context.strokeStyle = "black";
  context.stroke();

  context.textAlign = "right";
  context.textBaseline = "middle";
  yTicks.forEach(function(d) {
    context.fillText(yTickFormat(d), -9, y(d));
  });

  context.beginPath();
  context.moveTo(-6.5, 0 + 0.5);
  context.lineTo(0.5, 0 + 0.5);
  context.lineTo(0.5, height + 0.5);
  context.lineTo(-6.5, height + 0.5);
  context.strokeStyle = "black";
  context.stroke();

  context.save();
  context.rotate(-Math.PI / 2);
  context.textAlign = "right";
  context.textBaseline = "top";
  context.font = "bold 10px sans-serif";
  context.fillText("Frequency", -10, 10);
  context.restore();

  context.fillStyle = "steelblue";
  data.forEach(function(d) {
    context.fillRect(x(d.letter), y(d.frequency), x.bandwidth(), height - y(d.frequency));
  });
});

</script>
	letter	frequency
	A	.08167
	B	.01492
	C	.02782
	D	.04253
	E	.12702
	F	.02288
	G	.02015
	H	.06094
	I	.06966
	J	.00153
	K	.00772
	L	.04025
	M	.02406
	N	.06749
	O	.07507
	P	.01929
	Q	.00095
	R	.05987
	S	.06327
	T	.09056
	U	.02758
	V	.00978
	W	.02360
	X	.00150
	Y	.01974
	Z	.00074
	<!DOCTYPE html>
	<meta charset="utf-8">
	<canvas width="960" height="500"></canvas>
	<script src="//d3js.org/d3.v4.0.0-alpha.4.min.js"></script>
	<script>

	var canvas = document.querySelector("canvas"),
	context = canvas.getContext("2d");

	var margin = {top: 20, right: 20, bottom: 30, left: 40},
	width = canvas.width - margin.left - margin.right,
	height = canvas.height - margin.top - margin.bottom;

	var x = d3.scaleBand()
	.rangeRound([0, width])
	.padding(0.1);

	var y = d3.scaleLinear()
	.rangeRound([height, 0]);

	context.translate(margin.left, margin.top);

	d3.requestTsv("data.tsv", function(d) {
	d.frequency = +d.frequency;
	return d;
	}, function(error, data) {
	if (error) throw error;

	x.domain(data.map(function(d) { return d.letter; }));
	y.domain([0, d3.max(data, function(d) { return d.frequency; })]);

	var yTickCount = 10,
	yTicks = y.ticks(yTickCount),
	yTickFormat = y.tickFormat(yTickCount, "%");

	context.beginPath();
	x.domain().forEach(function(d) {
	context.moveTo(x(d) + x.bandwidth() / 2, height);
	context.lineTo(x(d) + x.bandwidth() / 2, height + 6);
	});
	context.strokeStyle = "black";
	context.stroke();

	context.textAlign = "center";
	context.textBaseline = "top";
	x.domain().forEach(function(d) {
	context.fillText(d, x(d) + x.bandwidth() / 2, height + 6);
	});

	context.beginPath();
	yTicks.forEach(function(d) {
	context.moveTo(0, y(d) + 0.5);
	context.lineTo(-6, y(d) + 0.5);
	});
	context.strokeStyle = "black";
	context.stroke();

	context.textAlign = "right";
	context.textBaseline = "middle";
	yTicks.forEach(function(d) {
	context.fillText(yTickFormat(d), -9, y(d));
	});

	context.beginPath();
	context.moveTo(-6.5, 0 + 0.5);
	context.lineTo(0.5, 0 + 0.5);
	context.lineTo(0.5, height + 0.5);
	context.lineTo(-6.5, height + 0.5);
	context.strokeStyle = "black";
	context.stroke();

	context.save();
	context.rotate(-Math.PI / 2);
	context.textAlign = "right";
	context.textBaseline = "top";
	context.font = "bold 10px sans-serif";
	context.fillText("Frequency", -10, 10);
	context.restore();

	context.fillStyle = "steelblue";
	data.forEach(function(d) {
	context.fillRect(x(d.letter), y(d.frequency), x.bandwidth(), height - y(d.frequency));
	});
	});

	</script>