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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <h1>Visualize Data with a Heat Map</h1>
<p><a href="https://youtu.be/w4jAkHd7qlE" target="_blank">Video tutorial</a></p>

<div class="graph">
  <svg id="heatmap"></svg>
  <div class="tooltip"></div>

<!-- Footer-->
<div class="row text-center">
			<div class="col-xs-12">
				<div class="tableFooter">
				  <!-- for footer -->
      <div class="col-xs-6">
      <h5><a href="http://www.eleftheriabatsou.com" target="_blank">Eleftheria</a> | <a href="https://codepen.io/EleftheriaBatsou" target="_blank">Projects</a> | <a href="https://www.youtube.com/channel/UCC-WwYv3DEW7Nkm_IP6VeQQ" target="_blank"> Coding videos </a></h5>
      <!-- social media -->
      <div class="col-xs-6 text-primary">
        <a href="https://twitter.com/BatsouElef" target="_blank">
     <img class="footerSvg"src="https://image.flaticon.com/icons/svg/60/60580.svg" 
      style="text-align:center" alt="twitter"> 
         <a href="https://github.com/EleftheriaBatsou" target="_blank">
     <img class="footerSvg" src="https://image.flaticon.com/icons/svg/25/25657.svg" 
      style="text-align:center" alt="github"> 
        <a href="https://www.youtube.com/channel/UCC-WwYv3DEW7Nkm_IP6VeQQ" target="_blank">
     <img class="footerSvg" src="https://image.flaticon.com/icons/svg/25/25312.svg" 
       style="text-align:center" alt="youtube"> 
    <!-- end footer -->
<!-- end of Footer -->
              body {
 text-align: center;
h1, h3, p{

.graph {
  margin: 0 auto;
  background-color: white; 

.tooltip {
  background-color: lightsalmon;
  border: 1px solid black;
  width: 100px;
  opacity: 0;
  color: black;
  position: absolute;

 * Footer
a:link    {color:orangered;  text-decoration:none}
a:visited {color:orangered; text-decoration:none}
a:hover   {color:red; text-decoration:underline}

  margin-top: 15px;
  width: 32px;
              var height = 500, width = 1000,
    margin = {
      left: 120, right: 20, top: 20, bottom: 70
    url = "https://raw.githubusercontent.com/FreeCodeCamp/ProjectReferenceData/master/global-temperature.json",
    months = ["January","February","March","April","May","June","July","August","September","October","November","December"],
    color = ["#ef5350","#EC407A","#AB47BC","#7E57C2","#5C6BC0","#42A5F5","#26C6DA","#26A69A","#D4E157","#FFEE58","#FFA726"];

var canvas = d3.select('svg').attr({
  height: height + margin.top + margin.bottom,
  width: width + margin.left + margin.right

var group = canvas.append('g').attr({
  transform: "translate(" + margin.left + "," + margin.top + ")"

var div = d3.select('.tooltip');
var xScale = d3.time.scale().range([0,width]);
var yScale = d3.scale.ordinal().domain(months).rangeBands([0,height]);
var colorScale = d3.scale.quantize().range(color);

//call the json with the url and a function
  data = data.monthlyVariance;
  //map the data
    d.month = months[d.month-1];
    d.year = d3.time.format("%Y").parse(d.year.toString());
  //declair the function xScale
    return data.year;
  //scale the colors
    return d.variance;
  var barWidth = width / (data.length / 12)
  var barHeight = height / 12;
  //scale the axis and set orientation
  var xAxis = d3.svg.axis().scale(xScale).orient("bottom");
  var yAxis = d3.svg.axis().scale(yScale).orient("left").ticks(12);
  //add a g element that provides a reference point for adding the axes.
  //append the axis according to the size and the position that we have set up with our width, height and margin’s.
    class: "xAxis",
    transform: "translate(0," + (height) + ")"
    class: "yAxis",
    transform: "translate(0,0)",
    transform: function(data){
      return "translate(" + xScale(data.year) + "," + yScale(data.month) +  ")";
    }).append('rect').attr({ //append the rectangulars and scale them in the graph
    width: barWidth,
    height: yScale.rangeBand()
  }).style({ //scale the colors
    fill: function(data){
     return colorScale(data.variance);
    //make the tooltip to follow the mouse
      left: d3.event.pageX + "px",
      top: d3.event.pageY + "px"
    //appear/disappear the tooltip on mouse hover
    //8.66 is a standard value
    div.html("<p>Year: " + d3.time.format("%Y")(d.year) + "</p></p>Value = " + (8.66 + d.variance).toFixed(2) + "</p><p>Month: " + d.month + "</p>" );

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