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HIS 697-Data Analysis
Public
Edited
Apr 7
Importers
2
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us = d3.json("https://cdn.jsdelivr.net/npm/us-atlas@3/counties-10m.json")
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states = topojson.feature(us, us.objects.states)
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nation = topojson.feature(us, us.objects.nation)
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Plot.plot({
projection: "albers-usa",
marks: [Plot.geo(states, { strokeOpacity: 0.4 })]
})
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nhgis0001_ds12_1850_state.csv
Type Table, then Shift-Enter. Ctrl-space for more options.

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nhgis0001_ds12_1850_state_codebook = FileAttachment("nhgis0001_ds12_1850_state_codebook.txt").text()
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freeblackpop1850Lookup = {
const k = "STATE";
const v = "AGN004";
return new Map(freeblackpop1850.map((x) => [x[k], +x[v]]));
}
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freeblackpop1850Lookup.get("Virginia")
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Plot.plot({
projection: "albers-usa",
color: {
type: "sequential",
scheme: "OrRd",
legend: true
},
title: "Free Black Population in 1850",
marks: [
Plot.geo(states, {
fill: (d) => freeblackpop1850Lookup.get(d.properties.name),
stroke: "lightgray"
}),
Plot.geo(nation, { stroke: "black" })
]
})
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