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Nicolas Lambert
Hi. I'm Nicolas Lambert, research engineer in geographic information science at CNRS (France). My job is to draw maps and teach cartography at the university. I am a geographer 🌎, and not really a developer 🖥️
Public
Geographic libraries
Edited
Nov 15
7 stars
2
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topohelper = import("https://cdn.jsdelivr.net/npm/topohelper@latest/+esm")
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world = FileAttachment("world.json").json()
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worldtopo = topohelper.fromGeojson(world).topojson
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topo = topohelper.from(worldtopo, { deep: true })
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topo.view({ tooltip: true, zoom: true })
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viewof level = Inputs.range([1, 0], { label: "Level", step: 0.1 })
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simplify = topohelper.from(worldtopo, { deep: true }).simplify({ level })
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simplify.view({ tooltip: true, zoom: true })
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world
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geo = topohelper
.from(worldtopo, { deep: true })
// add a layer with continent borders
.innerlines({
layer: 0, // derive from first layer
groupby: "region", // group by a property
name: "region_borders" // new layer name
})
// add a layer with outline of basemap
.outerlines({ layer: 0, name: "outline" })
// add centroids of nuts-3
.centroids({ layer: 0 })
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geo.view({ tooltip: true, zoom: true })
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arr = geo.toGeojson()
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arr[2]
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