Visualization toolmaker. Founder @observablehq. Creator @d3. Former @nytgraphics. Pronounced BOSS-tock.
Published
Edited
Feb 12, 2019
1 fork
2 stars
chart = {
const svg = d3.select(DOM.svg(width, height));
svg.append("g")
.call(xAxis);
svg.append("g")
.call(yAxis);
svg.append("path")
.datum(data)
.attr("fill", "none")
.attr("stroke", "steelblue")
.attr("stroke-width", 1.5)
.attr("stroke-linejoin", "round")
.attr("stroke-linecap", "round")
.attr("d", line);
return svg.node();
}
height = 500
margin = ({top: 20, right: 30, bottom: 30, left: 40})
x = d3.scaleTime()
.domain(d3.extent(data, d => d.date))
.range([margin.left, width - margin.right])
y = d3.scaleLog()
.domain([d3.min(data, d => d.value * 0.99), d3.max(data, d => d.value / 0.99)])
.range([height - margin.bottom, margin.top])
xAxis = g => g
.attr("transform", `translate(0,${height - margin.bottom})`)
.call(d3.axisBottom(x).ticks(width / 80).tickSizeOuter(0))
.call(g => g.select(".domain").remove())
yAxis = g => g
.attr("transform", `translate(${margin.left},0)`)
.call(d3.axisLeft(y)
.tickValues(d3.scaleLinear().domain(y.domain()).ticks())
.tickFormat(formatChange))
.call(g => g.selectAll(".tick line")
.select(function() { return this.parentNode.appendChild(this.cloneNode()); })
.attr("stroke-opacity", d => d === 1 ? null : 0.2)
.attr("x2", width - margin.left - margin.right))
.call(g => g.select(".domain").remove())
formatChange = {
const formatPercent = d3.format("+.0%");
return x => x === 1 ? "0%" : formatPercent(x - 1);
}
line = d3.line()
.x(d => x(d.date))
.y(d => y(d.value))
data = (await (await fetch("https://min-api.cryptocompare.com/data/histominute?fsym=BTC&tsym=USD&aggregate=2&limit=720&e=CCCAGG")).json()).Data.map((d, i, data) => {
return {
date: new Date(d.time * 1000),
value: d.close / data[0].close
};
})
value = data[data.length - 1].value
d3 = require("d3@5")
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
