javascript-d3How do I create a radar chart with d3.js?

Creating a radar chart with d3.js is relatively straightforward. First, you will need to include the d3 library in your HTML file:

<script src="https://d3js.org/d3.v5.min.js"></script>

Next, you will need to create the SVG element and set its size:

var svg = d3.select('body').append('svg')
    .attr('width', width)
    .attr('height', height);

Third, you will need to create the scales for the chart. This will depend on the data you are plotting. For example, if you are plotting a chart with two variables, you might use something like this:

var x = d3.scaleLinear()
    .domain([0, d3.max(data, function(d) { return d[0]; })])
    .range([0, width]);

var y = d3.scaleLinear()
    .domain([0, d3.max(data, function(d) { return d[1]; })])
    .range([height, 0]);

Fourth, you will need to create the axes for the chart. This will depend on the data you are plotting. For example, if you are plotting a chart with two variables, you might use something like this:

var xAxis = d3.axisBottom(x);

var yAxis = d3.axisLeft(y);

svg.append("g")
    .attr("transform", "translate(0," + height + ")")
    .call(xAxis);

svg.append("g")
    .call(yAxis);

Fifth, you will need to create the line for the chart. This will depend on the data you are plotting. For example, if you are plotting a chart with two variables, you might use something like this:

var line = d3.line()
    .x(function(d) { return x(d[0]); })
    .y(function(d) { return y(d[1]); });

svg.append("path")
    .datum(data)
    .attr("fill", "none")
    .attr("stroke", "steelblue")
    .attr("stroke-linejoin", "round")
    .attr("stroke-linecap", "round")
    .attr("stroke-width", 1.5)
    .attr("d", line);

Finally, you will need to add labels to the chart. This will depend on the data you are plotting. For example, if you are plotting a chart with two variables, you might use something like this:

svg.selectAll(".dot")
    .data(data)
    .enter().append("text")
    .attr("fill", "black")
    .attr("font-size", 10)
    .attr("x", function(d) { return x(d[0]); })
    .attr("y", function(d) { return y(d[1]); })
    .text(function(d) { return d[0] + ", " + d[1]; });

The above code will create a basic radar chart with d3.js.

Parts of the code:

Include the d3 library: <script src="https://d3js.org/d3.v5.min.js"></script>

Create the SVG element and set its size:

var svg = d3.select('body').append('svg')
  .attr('width', width)
  .attr('height', height);

Create the scales for the chart:

var x = d3.scaleLinear()
  .domain([0, d3.max(data, function(d) { return d[0]; })])
  .range([0, width]);

var y = d3.scaleLinear()
  .domain([0, d3.max(data, function(d) { return d[1]; })])
  .range([height, 0]);

Create the axes for the chart:

var xAxis = d3.axisBottom(x);

var yAxis = d3.axisLeft(y);

svg.append("g")
  .attr("transform", "translate(0," + height + ")")
  .call(xAxis);

svg.append("g")
  .call(yAxis);

Create the line for the chart:

var line = d3.line()
  .x(function(d) { return x(d[0]); })
  .y(function(d) { return y(d[1]); });

svg.append("path")
  .datum(data)
  .attr("fill", "none")
  .attr("stroke", "steelblue")
  .attr("stroke-linejoin", "round")
  .attr("stroke-linecap", "round")
  .attr("stroke-width", 1.5)
  .attr("d", line);

Add labels to the chart:

svg.selectAll(".dot")
  .data(data)
  .enter().append("text")
  .attr("fill", "black")
  .attr("font-size", 10)
  .attr("x", function(d) { return x(d[0]); })
  .attr("y", function(d) { return y(d[1]); })
  .text(function(d) { return d[0] + ", " + d[1]; });

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