The avatar for @tombor
Thomas Ansart
Cartography and datavisualization at Sciences Po
Public
Topohelper
Edited
May 13, 2024
Paused
7 stars
1
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topohelper.from(topojson, {deep: true})
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lines = topohelper.from(topojson, {deep: true})
.lines()
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innerlines = topohelper.from(topojson, {deep: true})
.innerlines()
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innerlines_2 = topohelper.from(topojson, {deep: true})
.innerlines({groupby: "ADM1_PCODE"})
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outerlines = topohelper.from(topojson, {deep: true})
.outerlines()
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merge = topohelper.from(topojson, { deep: true }).merge({
groupby: "ADM1_PCODE"
})
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filter = topohelper.from(topojson, {deep: true})
// All ADM-2 of Sofia and Sofia City ADM-1
.filter({condition: d => ["BG020", "BG021"].includes(d.properties.ADM1_PCODE)})
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centroids = topohelper.from(topojson, {deep: true})
.centroids({better})
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simplify = topohelper.from(topojson, {deep: true})
.simplify({level})
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properties = topohelper.from(topojson, { deep: true }).properties({
select: ["ADM2_PCODE", "ADM2_EN", "Shape_Area"],
rename: { ADM2_PCODE: "id", ADM2_EN: "name", Shape_Area: "area" },
derive: { area_1000: (d) => d.area * 1000 }
})
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fourLayers.view({
layer: form.layer,
zoom: form.zoom,
tooltip: form.tooltip,
size: [form.width, form.width * 0.5]
})
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fourLayers.toTopojson()
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fourLayers.toTopojson({layer: [0,3]})
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fourLayers.toGeojson()
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fourLayers.toGeojson({layer: [0,3]})
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properties.toObjects()
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// Bulgaria administrative level 2
// https://data.humdata.org/dataset/cod-ab-bgr
topojson = FileAttachment("bgr_adm2_2022.json").json()
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