Simple animation at lollipop plot loading





This post describes how to add a simple animation when your lollipop chart loads. It's just a couple additional lines of code that add a bit of style to your work. Plus it is a good way to understand how animation work in d3. This example works with d3.js v4 and v6


Lollipop section

Steps:

  • Start by understanding the basic horizontal lollipop chart.

  • For the animation, first make the plot with dots and lines at x = 0. Then, change their positions to their true value using the transition() function.
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<!DOCTYPE html>
<meta charset="utf-8">

<!-- Load d3.js -->
<script src="https://d3js.org/d3.v4.js"></script>

<!-- Create a div where the graph will take place -->
<div id="my_dataviz"></div>

<!DOCTYPE html>
<meta charset="utf-8">
        
<!-- Load d3.js -->
<script src="https://d3js.org/d3.v6.js"></script>
        
<!-- Create a div where the graph will take place -->
<div id="my_dataviz"></div>
    
<script>

// set the dimensions and margins of the graph
var margin = {top: 10, right: 30, bottom: 40, left: 100},
    width = 460 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

// append the svg object to the body of the page
var svg = d3.select("#my_dataviz")
  .append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform",
          "translate(" + margin.left + "," + margin.top + ")");

// Parse the Data
d3.csv("https://raw.githubusercontent.com/holtzy/data_to_viz/master/Example_dataset/7_OneCatOneNum_header.csv", function(data) {

// sort data
data.sort(function(b, a) {
  return a.Value - b.Value;
});

// Add X axis
var x = d3.scaleLinear()
  .domain([0, 13000])
  .range([ 0, width]);
svg.append("g")
  .attr("transform", "translate(0," + height + ")")
  .call(d3.axisBottom(x))
  .selectAll("text")
    .attr("transform", "translate(-10,0)rotate(-45)")
    .style("text-anchor", "end");

// Y axis
var y = d3.scaleBand()
  .range([ 0, height ])
  .domain(data.map(function(d) { return d.Country; }))
  .padding(1);
svg.append("g")
  .call(d3.axisLeft(y))

// Lines
svg.selectAll("myline")
  .data(data)
  .enter()
  .append("line")
    .attr("x1", x(0))
    .attr("x2", x(0))
    .attr("y1", function(d) { return y(d.Country); })
    .attr("y2", function(d) { return y(d.Country); })
    .attr("stroke", "grey")

// Circles -> start at X=0
svg.selectAll("mycircle")
  .data(data)
  .enter()
  .append("circle")
    .attr("cx", x(0) )
    .attr("cy", function(d) { return y(d.Country); })
    .attr("r", "7")
    .style("fill", "#69b3a2")
    .attr("stroke", "black")

// Change the X coordinates of line and circle
svg.selectAll("circle")
  .transition()
  .duration(2000)
  .attr("cx", function(d) { return x(d.Value); })

svg.selectAll("line")
  .transition()
  .duration(2000)
  .attr("x1", function(d) { return x(d.Value); })

})

</script>
<script>

// set the dimensions and margins of the graph
const margin = {top: 10, right: 30, bottom: 40, left: 100},
    width = 460 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

// append the svg object to the body of the page
const svg = d3.select("#my_dataviz")
  .append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform",
          `translate(${margin.left}, ${margin.top})`);

// Parse the Data
d3.csv("https://raw.githubusercontent.com/holtzy/data_to_viz/master/Example_dataset/7_OneCatOneNum_header.csv").then( function(data) {

// sort data
data.sort(function(b, a) {
  return a.Value - b.Value;
});

// Add X axis
const x = d3.scaleLinear()
  .domain([0, 13000])
  .range([ 0, width]);
svg.append("g")
  .attr("transform", `translate(0, ${height})`)
  .call(d3.axisBottom(x))
  .selectAll("text")
    .attr("transform", "translate(-10,0)rotate(-45)")
    .style("text-anchor", "end");

// Y axis
const y = d3.scaleBand()
  .range([ 0, height ])
  .domain(data.map(function(d) { return d.Country; }))
  .padding(1);
svg.append("g")
  .call(d3.axisLeft(y))

// Lines
svg.selectAll("myline")
  .data(data)
  .join("line")
    .attr("x1", x(0))
    .attr("x2", x(0))
    .attr("y1", function(d) { return y(d.Country); })
    .attr("y2", function(d) { return y(d.Country); })
    .attr("stroke", "grey")

// Circles -> start at X=0
svg.selectAll("mycircle")
  .data(data)
  .join("circle")
    .attr("cx", x(0) )
    .attr("cy", function(d) { return y(d.Country); })
    .attr("r", "7")
    .style("fill", "#69b3a2")
    .attr("stroke", "black")

// Change the X coordinates of line and circle
svg.selectAll("circle")
  .transition()
  .duration(2000)
  .attr("cx", function(d) { return x(d.Value); })

svg.selectAll("line")
  .transition()
  .duration(2000)
  .attr("x1", function(d) { return x(d.Value); })

})
</script>

Related blocks →

  • The most basic barplot with d3.js - link

  • Lollipop chart - link

  • Horizontal Bar Chart Sort - link