7.11 animated line plot | stroke dashoffset

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<script src="https://d3js.org/d3.v3.min.js"></script>

<p id="h1">LINE CHART | ANIMATION </p>
<div id="link">by
<a href="https://slides.com/sandravizmad">SANDRA</a></div>

<style>

/*Defining text stylings*/

#h1 {
  font-size:30px;
  margin:30px 0px 0px 20px;
  color:#f5fa91;
  font-family:'Montserrat Alternates', sans-serif;
  font-weight:300;
}

#link {
	font-family:'Montserrat Alternates', sans-serif;
  font-weight:200;
  font-size:10px;
	margin:5px 0px 0px 22px;
  color:white;
}

a:link, a:visited, a:active {
	text-decoration: none;
  color:white;
  border-bottom:1.5px dotted white;
}

body {
  background-color:#011227;
}

/*Defining axis stylings*/

.y-axis text, .x-axis text {
  font-family:'Montserrat Alternates', sans-serif;
  font-weight:100;
  font-size:9px;
  opacity:1;
  fill:white;
}

.x-axis path, .y-axis path {
  fill:none;
  stroke-width:0;
  stroke-opacity:1;
  stroke:white;
}

.y-axis line, .x-axis line {
  fill:none;
  stroke-width:0;
  stroke-opacity:1;
  stroke:white;
  stroke-dasharray:2;
}

/*Defining chart stylings*/

.line {
   fill:none;
   stroke:white;
   stroke-width: 1px;
    }

.horizontalGrid {
   fill:none;
   stroke:white;
   stroke-width:0.5px;
   stroke-dasharray: 2;
    }

</style>
</head>

//Margin conventions
var m = {top:100, right:50, bottom:50, left:50}
    w = 600 - m.left - m.right,
    h = 600 - m.top - m.bottom;

//Container
var svg = d3.select("body")
    .append("svg")
    .attr("width", w + m.left + m.right)
    .attr("height", h + m.top + m.bottom)
    .append("g")
    .attr("transform", `translate(${m.left}, ${m.top})`);

//Date format
var parseDate = d3.time.format("%Y-%m-%d").parse;

//Data loading
d3.tsv(
  "https://gist.githubusercontent.com/sandravizz/3dc4d165961256625f0baff2664aaa2d/raw/7db03d6473a0cc409225d2bfc52e71a80f6a97b2/airbus%2520data", 
  data => {

//Color scale
var c = d3.scale.category10()
    .domain(d3.keys(data[0])
    .filter(function(key) {return key !== "date";}));

//Data format
data.forEach(d => {d.date = parseDate(d.date);});

var comp = c.domain()
  	.map(function(name) { return {
          name : name,values : data.map(d=> { return {
          date : d.date,price : +d[name]};})
};
});

//X scale
var x = d3.time.scale()
    .domain(d3.extent(data, d => d.date))
    .range([0, w]);

//Y scale
var y = d3.scale.linear()
    .domain([
      d3.min(comp, c => d3.min(c.values, v => v.price)),
      d3.max(comp, c => d3.max(c.values, v => v.price))])
    .range([h, 0]);

//Line genrator
var line = d3.svg.line()
    .interpolate("basis")
    .x(d => x(d.date))
    .y(d => y(d.price));

//Calling X axis
svg.append("g")
   .attr("class", "x-axis")
   .attr("transform", `translate(0, ${h})`)
   .call(d3.svg.axis()
    			 .scale(x)
   				 .ticks(5)
   				 .innerTickSize(2)
   				 .outerTickSize(0.5)
   				 .orient("bottom"));

//Calling Y axis
svg.append("g")
   .attr("class", "y-axis")
   .call(d3.svg.axis()
    			 .scale(y)
   				 .tickFormat(d => d+"%")
    			 .ticks(5)
  				 .innerTickSize(2)
   				 .outerTickSize(0.5)
    			 .orient("left"));

//Reference line
svg.append("line")
   .attr({"class":"horizontalGrid",
            "x1" : 0,
            "x2" : w,
            "y1" : y(0),
            "y2" : y(0)});

var company = svg.selectAll(".company")
    .data(comp)
   	.enter()
		.append("g")
    .attr("class", "company");

//Drawing the line
var p = svg.selectAll(".company")
  	.append("path")
    .attr("class", "line")
    .attr("d", d => line(d.values))
    .style("stroke", d => {if(d.name == "Airbus") { return "#8ff798" } else { return "#85f6fa";}});

//Preparation for the animation
var totalL = [p[0][0].getTotalLength(),
              p[0][1].getTotalLength()];

//Animation of the first line
d3.select(p[0][0])
  .attr("stroke-dasharray", totalL[0] +" "+ totalL[0])
  .attr("stroke-dashoffset", totalL[0])
  .transition()
  .duration(20000)
  .ease("linear")
  .attr("stroke-dashoffset", 0);

//Animation of the second line
d3.select(p[0][1])
  .attr("stroke-dasharray", totalL[1] +" "+ totalL[1])
  .attr("stroke-dashoffset", totalL[1])
  .transition()
  .duration(20000)
  .ease("linear")
  .attr("stroke-dashoffset", 0);

});

</script>
</body>
</html>

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