JSFiddle - React, Tailwind, and code Playground

by Shashank D

HTML

<script src="https://d3js.org/d3.v4.min.js"></script>
<!DOCTYPE html>
<body>
<svg width="960" height="500"></svg>
</body>

CSS

.line {
  stroke: #0058a6;
  clip-path: url(#clip);
	fill: none;
	stroke-width: 1;
}

.zoom {
  cursor: move;
  fill: none;
  pointer-events: all;
}

JavaScript

//var datapointCount = 15000; // This draws both!
//var datapointCount = 16000; // This draws just series!
var datapointCount = 16300; // This shows empty!

var data = []
var ts = 1485546053000;
for (var i=0; i< datapointCount; i++) {
	data.push([ ts + i*500, Math.random()*30+7 ]);
}


var svg = d3.select("svg"),
    margin = {top: 20, right: 20, bottom: 110, left: 40},
    margin2 = {top: 430, right: 20, bottom: 30, left: 40},
    width = +svg.attr("width") - margin.left - margin.right,
    height = +svg.attr("height") - margin.top - margin.bottom,
    height2 = +svg.attr("height") - margin2.top - margin2.bottom;

var x = d3.scaleTime().range([0, width]),
    x2 = d3.scaleTime().range([0, width]),
    y = d3.scaleLinear().range([height, 0]),
    y2 = d3.scaleLinear().range([height2, 0]);

var xAxis = d3.axisBottom(x),
    xAxis2 = d3.axisBottom(x2),
    yAxis = d3.axisLeft(y);

var brush = d3.brushX()
    .extent([[0, 0], [width, height2]])
    .on("brush end", brushed);

var zoom = d3.zoom()
    .scaleExtent([1, Infinity])
    .translateExtent([[0, 0], [width, height]])
    .extent([[0, 0], [width, height]])
    .on("zoom", zoomed);

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

var line2 = d3.line()
    .x(function(d) { return x2(new Date(d[0])); })
    .y(function(d) { return y2(d[1]); });

svg.append("defs").append("clipPath")
    .attr("id", "clip")
    .append("rect")
    .attr("width", width)
    .attr("height", height);

var focus = svg.append("g")
    .attr("class", "focus")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

var context = svg.append("g")
    .attr("class", "context")
    .attr("transform", "translate(" + margin2.left + "," + margin2.top + ")");

x.domain(d3.extent(data, function(d) { return new Date(d[0]); }));
y.domain([ 0, d3.max(data, function(d) { return d[1]; }) ]);
x2.domain(x.domain());
y2.domain(y.domain());

focus.append("path")
     ...