viewof datafile = Scrubber(datafiles, {
delay: 10,
loop: true,
autoplay: false
})
map = svg`<svg viewBox="0 0 975 610">
<g fill="none" stroke="#000" stroke-linejoin="round" stroke-linecap="round">
<path stroke="#aaa" stroke-width="0.5" d="${path(counties)}"></path>
<path stroke-width="0.5" d="${path(states)}"></path>
<path d="${path(nation)}"></path>
</g>
<g>
${data.map( (d,i) => `<circle
cx=${getLat( d.location )}
cy=${getLng( d.location )}
r=${3}
fill="steelblue"
data-idx=${i}
/>`).join('\n')}
</g>
</svg>`
getLat = (d) => {
let loc = projection([+d.longitude, +d.latitude])
return `${loc && loc[0]}`
}
getLng = (d) => {
let loc = projection([+d.longitude, +d.latitude])
return `${loc && loc[1]}`
}
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endpoint = `https://raw.githubusercontent.com/codecreative/train-tester/main/data/${datafile}`
data = {
if( !data_cache[datafile] ) {
console.log('fetching ', datafile);
let new_data = await fetch( endpoint )
.then((response) => response.json())
.then( json => json.filter( d => d.location ) )
mutable data_cache[datafile] = new_data;
return new_data
} else {
console.log('from cache', datafile)
return data_cache[datafile]
}
}
data_ = fetch( endpoint )
.then((response) => response.json())
.then( json => json.filter( d => d.location ) )
projection = d3.geoAlbersUsa().scale(1300).translate([487.5, 305])
path = d3.geoPath()
states = topojson.mesh(us, us.objects.states, (a, b) => a !== b)
nation = topojson.feature(us, us.objects.nation)
counties = topojson.mesh(us, us.objects.counties, (a, b) => a !== b && (a.id / 1000 | 0) === (b.id / 1000 | 0))
us = FileAttachment("counties-albers-10m.json").json()
topojson = require("topojson-client@3")
d3 = require("d3-geo@2")
import { Scrubber } from "@mbostock/scrubber"
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.
