Signal Plot I

Simple line chart that displays three dimensions of data taken from an accelerometer.

This is meant to be a very basic example of using a d3 line chart, while plotting multiple lines.

Note: some of the syntax has been simplified using ES6 arrow functions.

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
<style>
body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
    
.line {
  fill: none;
  opacity: 0.9;
  stroke-width: 1.5px;
}

.line--x {
  stroke: steelblue;
}
  
.line--y {
  stroke: red;
}

.line--z {
  stroke: purple;
}

</style>
</head>

<body>
<script>
// set the dimensions and margins of the graph
var margin = {top: 20, right: 40, bottom: 30, left: 50},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

// the different dimensions in the data
var dims = ['x', 'y', 'z'];

// set x-range
var x = d3.scaleLinear().range([0, width]);
  
// set the y-ranges
var Y = {}
dims.forEach(dim => {
  Y[dim] = d3.scaleLinear().range([height, 0]);
});

// define the line functions for each dimension
var lines = {}
dims.forEach(dim => { 
  lines[dim] = d3.line()
    .x(d => x(d.tick))
    .y(d => Y[dim](d[dim]));
});

// create the svg object
var svg = d3.select("body").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 + ")");

// process the data
d3.csv("accel-data.csv",(error, data) => {
  if (error) throw error;
  
  // Parse the data
  data.forEach(d => {
      d.tick = +d.tick;
      d.x = +d.x;
      d.y = +d.y;
      d.z = +d.z;
  });
  // Set domain scales
  x.domain(d3.extent(data, d => d.tick));
  for(var dim of dims) {
    Y[dim].domain(d3.extent(data, d => d[dim]));
  }
  
  // Draw Paths
  for (var dim of dims) {
    svg.append("path")
    	  .data([data])
        .attr("class", "line line--"+dim)
        .attr("d", d => lines[dim](d));
  }
  
  // Add the X Axis
  svg.append("g")
      .attr("transform", "translate(0," + height + ")")
      .call(d3.axisBottom(x));
  
  // Add the Y Axis (Note how we only need one axis)
  svg.append("g")
      .attr("class", "axisSteelBlue")
      .call(d3.axisLeft(Y['x']));
});
    
</script>
</body>

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