JSFiddle - React, Tailwind, and code Playground

by grenblau

HTML

<!DOCTYPE html>
<html lang="en">
  <head>

    <script type="text/javascript" src="https://d3js.org/d3.v6.min.js"></script>
  </head>
  <body>
    <div class="chart"></div>
       <!-- <script src="arcExample.js">    </script>-->
  </body>
</html>

JavaScript

// (1) This version uses the json in a variable called data and does not use the d3.json call.  This is not a solution because I need to be able to read the json data from a file.
// (2) It also does not use the grads variable (radialGradients) to fill the arcs
// It has the virtue that it works, but it doesn't do what I want
var width = window.innerWidth,
    height = window.innerHeight;

var body = d3.select('body')

// append svg to the DIV
chart = d3.select(".chart");

const svg = chart.append("svg:svg")
    .attr("width", width)
    .attr("height", height);

///////////////////////////////////////  Global variables controlling the arc appearance //////////////////
const arcMin = 30;
const arcWidth = 45.5;
const arcPad = 1;
///////////////////////////////////////////////////////////////////////////////////////////////
data={"type":"sequenceData","sequences":[{"pulse":1,"code":0},{"pulse":1,"code":1},{"pulse":1,"code":2},{"pulse":2,"code":3},{"pulse":2,"code":4},{"pulse":2,"code":5},{"pulse":2,"code":6},{"pulse":2,"code":7},{"pulse":2,"code":8},{"pulse":2,"code":9},{"pulse":2,"code":10},{"pulse":3,"code":12}]};
//d3.json("https://gitlab.com/evodevosys/stackoverflowdata/-/raw/master/d3ArcGradientExample.json").then(function (data) {

        const grads = svg.append("defs").selectAll("radialGradient").data(data.sequences);
        grads.enter().append("radialGradient")
            .attr("gradientUnits", "objectBoundingBox")
            .attr("cx", 0)
            .attr("cy", 0)
            .attr("fr", (d, i) => arcMin + (d.pulse-1) * (arcWidth))
            .attr("r", (d, i) => arcMin + d.pulse * (arcWidth))
            .attr("id", function (d) {
                return "grad" + d.code;
            });
        grads.append("stop")
            .attr("offset", "0%").style("stop-color", "white")
            .attr("offset", "100%").style("stop-color", "green");//eventually this gradient will go between two colors that are functions of the data that is read in from...