dataviz & research
Public
Edited
Apr 19, 2021
import {get_journeys} from "529140a6d468cf32"
isochrone_color = d3
.scaleLinear()
.domain([0, max_duration])
.range(["white", "royalblue"])
function predecessor(i) {
const duration = +data[i].duration;
// which is the nearest among points that are bigger than me
return d3.scan(
data.map((d, j) =>
+d.duration < duration
? d3.geoDistance(points[i], points[j]) *
Math.sqrt(duration / +d.duration)
: Infinity
)
);
}
// How many seconds walking, per pixel?
walkingtime = {
// At the equator 40000km ~= 960px * projection.scale() / d3.geoMercator().scale()
// multiply by cos(latitude)
const scale =
walkingspeed /
(((40000 * Math.cos(projection.center()[1] * radians)) /
960 /
projection.scale()) *
d3.geoMercator().scale() *
3600);
return function(T) {
return T * scale;
};
}
path = d3.geoPath().projection(projection)
rawpath = d3.geoPath()
import {tile, nextzenapikey} with {largeprojection as projection} from "17564db3a49dd521"
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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.
