6.10 area chart | ridgline

<!DOCTYPE html>
<meta charset="utf-8">
<html>
<head>

<link href="https://fonts.googleapis.com/css2?family=Montserrat+Alternates:ital,wght@0,100;0,200;0,300;0,400;0,500;0,600;0,700;0,800;0,900;1,100;1,200;1,300;1,400;1,500;1,600;1,700;1,800;1,900&family=Montserrat:ital,wght@0,100;0,200;0,300;0,400;0,500;0,600;0,700;0,800;0,900;1,100;1,200;1,300;1,400;1,500;1,600;1,700;1,800;1,900&family=Roboto:ital,wght@0,100;0,300;1,100;1,300&display=swap" rel="stylesheet">

<script src="https://d3js.org/d3.v4.min.js"></script>

<p id="h1">AREAS | RIDGLINE</p>
<div id="link"> by
<a href="https://slides.com/sandravizmad">SANDRA</a> | <a href="https://data.oecd.org/agroutput/meat-consumption.htm">DATA </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 chart stylings*/

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

.area {
  fill:#85f6fa;
  stroke:none;
}

.activity:nth-child(odd)
.area {
  fill:#8ff798;
}

/*Defining axis stylings*/

.y-axis text, .x-axis text {
  font-family:'Montserrat Alternates', sans-serif;
  font-weight:100;
  font-size:10px;
  opacity:1;
  fill:white;
}

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

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

.y-axis line, .x-axis line {
  fill:none;
  stroke-width:0.1;
  stroke-opacity:0.5;
  stroke:white;
  stroke-dasharray:2;
}

</style>
</head>

//Margin conventions
var m = {top:80, right:20, bottom:50, left:200}
    w = 1000 - m.left - m.right,
    h = 900 - 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})`);

//Data format
var formatTime = d3.timeFormat('%I %p');

function parseTime(offset) {
  var date = new Date(2017, 0, 1);
  return d3.timeMinute.offset(date, offset);
}

//Data loading
d3.tsv(
  'https://gist.githubusercontent.com/sandravizz/634e39e1e41fc6ef993df149afdd538c/raw/b497b9d33fcaf94e2ab728a266836dc1211335ef/data.tsv',
  prepare,
  data => {

//Sort by time
  data.sort((a,b) => a.time - b.time);

//Nest data
  var data_nested = d3.nest()
      .key(d => d.activity)
      .entries(data);

//Check
  console.log(data_nested);

//Y visual encoding
  var yvar = d => d.value;

//Y2 scaled visual encoding
  var yValue2 = d => y2(d.key);

//Defining peaktime
  function peakTime(d)
    {var i = d3.scan(d.values,(a,b) => yvar(b) - yvar(a));
     return d.values[i].time;
   };

//Sort by peaktime
  data_nested.sort((a,b) => peakTime(b) - peakTime(a));

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

//X axis
  svg.append("g")
  	  .attr("class", "x-axis")
  	  .attr("transform", `translate(0, ${h})`)
  	  .call(d3.axisBottom()
  					 .scale(x)
  					 .ticks(3)
             .tickFormat(formatTime));

//Y2 scale
  var y2 = d3.scaleBand()
      .domain(data_nested.map( d => d.key))
  	  .range([0, h]);

//Y axis
  svg.append("g")
      .attr("class", "y-axis")
      .call(d3.axisLeft(y2));

//Help varaible
  var areaHeight = h/y2.domain().length;

//Y scale
  var y = d3.scaleLinear()
      .domain(d3.extent(data, yvar))
      .range([areaHeight,0]);

//Area generator
  var area = d3.area()
      .x(d => x(d.time))
      .y1(d => y(yvar(d)))
  		.y0(y(0));

//Line generator
  var line = d3.line()
      .x(d => x(d.time))
      .y(d => y(yvar(d)));

//Create the small containers
  var small_svg = svg.append('g')
      .selectAll('.activity')
  		.data(data_nested)
      .enter()
  		.append('g')
      .attr('class', d => 'activity activity--' + d.key)
      .attr('transform',d => {var ty = yValue2(d)- y2.bandwidth();
                              return 'translate(0,'+ ty +')';});

//Draw the area
  small_svg.append('path')
    	.attr('class', 'area')
      .datum(d => d.values)
      .attr('d', area);

//Draw the line
  small_svg.append('path')
      .attr('class', 'line')
      .datum(d => d.values)
      .attr('d', line);
});

//Data format
function prepare(d) {return {
  activity : d.activity,
  time : parseTime(d.time),
  value : +d.p_smooth
};
}

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

https://d3js.org/d3.v4.min.js