quickselect VS d3.median by fil

Exploring mourner/quickselect as a faster alternative to compute d3.median()

Note: a better alternative is probably simplestatistics.

index.html

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <script src="https://unpkg.com/quickselect"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  </style>
</head>
<body>
  <script>
    // Feel free to change or delete any of the code you see in this editor!
    var svg = d3.select("body").append("svg")
      .attr("width", 960)
      .attr("height", 500)

    const data = d3.range(1000000).map(Math.random);
    
    let timem = performance.now();
    const m = d3.median(data);
    timem -= performance.now();

    let timeq = performance.now();
    partialSort(data, data.length/2);
    partialSort(data, data.length/2-1);
    const q = (data[data.length/2-1] + data[data.length/2]) / 2;
    timeq -= performance.now();
    
    svg.append("text")
      .text(`Result: ${m == q} ; quickselect time is ${d3.format('3.1%')(timeq/timem)} of d3.median time`)
      .attr("y", 200)
      .attr("x", 120)
      .style("font-size", 20)
      .style("font-family", "monospace")

  </script>
</body>