JSFiddle - React, Tailwind, and code Playground
HTML
<script src="https://cdn.rawgit.com/mbostock/d3/master/d3.js"></script>
JavaScript
var q = d3.scale.quantize().domain([0, 1]).range(['a', 'b', 'c']);
console.log(q(0.411));
var ql = d3.scale.quantile().domain([0,1,10000]).range(['a','b','c']);
console.log(ql(999));