Visualization toolmaker. Founder @observablehq. Creator @d3. Former @nytgraphics. Pronounced BOSS-tock.
Published
Edited
Aug 26, 2021
1 fork
20 stars
chart = {
const svg = d3.create("svg")
.attr("viewBox", [0, 0, width, height]);
svg.append("g")
.call(xAxis);
svg.append("g")
.call(yAxis);
svg.append("g")
.call(grid);
const trail = svg.append("path")
.attr("fill", "none")
.attr("stroke", "gray")
.attr("stroke-width", 0.5)
.attr("stroke-miterlimit", 1);
const path = svg.append("path")
.attr("fill", "none")
.attr("stroke", "red")
.attr("stroke-miterlimit", 1)
.attr("stroke-width", 2);
const dot = svg.append("circle")
.attr("fill", "red")
.attr("r", 4);
return Object.assign(svg.node(), {
update(date) {
const i = bisectDate(data, d3.utcMonth.offset(date, -3), 0);
const j = bisectDate(data, date, 0);
trail.attr("d", line(data.slice(0, i)));
path.attr("d", line(data.slice(Math.max(0, i - 1), j)));
dot.attr("cx", x(data[j - 1].volume)).attr("cy", y(data[j - 1].extent));
}
});
}
chart.update(date)
data = Array.from(d3.rollup([].concat(
extent.map(d => ({...d, type: "extent"})),
volume.map(d => ({...d, type: "volume"})),
), v => v.pop(), d => +d.date, d => d.type))
.filter(([, group]) => group.has("extent") && group.has("volume"))
.map(([date, group]) => ({
date: new Date(date),
extent: group.get("extent").value,
volume: group.get("volume").value
}))
extent = {
const parseDate = d3.utcParse("%B %d, %Y");
let month;
let date;
return d3.csvParseRows(await FileAttachment("Sea_Ice_Index_Daily_Extent_G02135_v3.0.csv").text(), (row, i) => {
if (i === 0) return;
if (row[0] !== "") month = row[0];
if (row[1] !== "") date = row[1];
return row
.slice(2)
.map((value, i) => ({
date: parseDate(`${month} ${date}, ${i + 1978}`),
value: value === "" ? null : +value
}))
.filter(({value}) => value !== null);
})
.flat(1)
.sort((a, b) => d3.ascending(a.date, b.date));
}
volume = d3.csvParse((await FileAttachment("PIOMAS.vol.daily.1979.2020.Current.v2.1.dat").text()).replace(/[ ]+/g, ","), ({Year: year, ["#day"]: day, Vol: volume}) => ({date: new Date(Date.UTC(year, 0, day)), value: +volume}))
bisectDate = d3.bisector(d => d.date).left
line = d3.line()
.x(d => x(d.volume))
.y(d => y(d.extent))
x = d3.scaleLinear()
.domain([0, d3.max(data, d => d.volume)]).nice()
.rangeRound([margin.left, width - margin.right])
y = d3.scaleLinear()
.domain([0, d3.max(data, d => d.extent)]).nice()
.rangeRound([height - margin.bottom, margin.top])
xAxis = g => g
.attr("transform", `translate(0,${height - margin.bottom})`)
.call(d3.axisBottom(x).ticks())
.call(g => g.append("text")
.attr("x", width)
.attr("y", margin.bottom - 4)
.attr("fill", "currentColor")
.attr("text-anchor", "end")
.text("Volume (thousands of km³) →"))
yAxis = g => g
.attr("transform", `translate(${margin.left},0)`)
.call(d3.axisLeft(y))
.call(g => g.append("text")
.attr("x", -margin.left)
.attr("y", 10)
.attr("fill", "currentColor")
.attr("text-anchor", "start")
.text("↑ Extent (millions of km²)"))
grid = g => g
.attr("stroke", "currentColor")
.attr("stroke-opacity", 0.1)
.call(g => g.append("g")
.selectAll("line")
.data(x.ticks())
.join("line")
.attr("x1", d => 0.5 + x(d))
.attr("x2", d => 0.5 + x(d))
.attr("y1", margin.top)
.attr("y2", height - margin.bottom))
.call(g => g.append("g")
.selectAll("line")
.data(y.ticks())
.join("line")
.attr("y1", d => 0.5 + y(d))
.attr("y2", d => 0.5 + y(d))
.attr("x1", margin.left)
.attr("x2", width - margin.right));
height = 640
margin = ({top: 20, right: 20, bottom: 36, left: 30})
import {Scrubber} from "@mbostock/scrubber"
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