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 🖥️
Map projectionsh3-jsSymbolsThe draw() functionsquareProportional symbolsSpike markTypologyChoroplethLayout marksHandle geometriesSVG filters and clipTile markContainersinsetsPath markText markInteractivityTooltipsLegendsRidgelines mapWhy it's better not to add scalebars to world mapsNight and dayPan and zoomCharging points for electric vehicles in ParisLet's design a "dot cartogram"Hello geovizWorld Population
Circle mark
viz.circle({ r: 40, fill: "#38896F" })
viz.plot({ type: "circle", r: 40, fill: "#38896F" })
{
// Container
let svg = viz.create({
width: 500,
domain: world,
zoomable: true
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Circle
svg.circle({
pos: position,
fill: "#38896F"
});
// Render
return svg.render();
}
mumbai = [72.88, 19.07]
Type HTML, then Shift-Enter. Arrow ↑/↓ to switch modes.
{
// Container
let svg = viz.create({
domain: world,
width: 500,
zoomable: true
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Circle
svg.circle({
coords: "geo",
pos: mumbai,
fill: "#38896F"
});
// Render
return svg.render();
}
{
// Container
let svg = viz.create({
width: 500,
zoomable: true,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Circles
svg.circle({
data: world,
r: 4,
fill: "#38896F"
});
// Render
return svg.render();
}
{
// Container
let svg = viz.create({
width: 500,
zoomable: true,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Circles
svg.circle({
data: world,
r: "pop",
k: 30,
sort: "pop",
fill: "#38896F"
});
// Render
return svg.render();
}
{
// Container
let svg = viz.create({
width: 500,
zoomable: true,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Circles
svg.circle({
data: world,
r: (d) => Math.sqrt(d.properties.pop / 2000000),
sort: (a, b) =>
d3.descending(Math.abs(+a.properties.pop), Math.abs(+b.properties.pop)),
fill: "#38896F"
});
// Render
return svg.render();
}
radius = viz.tool.radius(
world.features.map((d) => d.properties.pop),
{ k: 40, fixmax: undefined }
)
{
// Container
let svg = viz.create({
width: 500,
zoomable: true,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Circles
svg.circle({
data: world,
r: (d) => radius.r(d.properties.pop),
sort: "pop",
fill: "#38896F"
});
// Render
return svg.render();
}
viz.legend.circles({ circle_fill: "#38896F" })
{
// Container
let svg = viz.create({
width: 1000,
zoomable: true,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Circles
svg.circle({
data: world,
r: (d) => radius.r(d.properties.pop),
sort: "pop",
fill: "#38896F"
});
// Legend
svg.legend.circles_nested({
pos: [70, 260],
gap: 10,
title: "Number of inh.",
data: radius.data,
k: radius.k
});
// Render
return svg.render();
}
viz.circle({
data: world,
r: 8,
dodge: true,
fill: "#38896F"
})
viz.circle({
data: world,
r: "pop",
dodge: true,
fill: "#38896F"
})
{
// Container
let svg = viz.create({
width: 500,
domain: world
});
// Basemap
svg.path({ datum: world, fill: "#CCC" });
// Circle
svg.circle({
r: 20,
fillOpacity: 0.5,
pos: position,
fill: "#38896F"
});
// Translated circle
svg.circle({
r: 20,
pos: position,
fill: "#38896F",
transform: "translate(40,0)"
});
// Render
return svg.render();
}
{
// Container
let svg = viz.create({
width: 800,
domain: africa,
zoomable: true,
background: "#b7e9f7",
margin: 30
});
svg.path({ datum: world, fill: "white", fillOpacity: 0.4 });
svg.path({ datum: africa, fill: "#F5DA7E", stroke: "white" });
svg.header({ text: "Population and wealth in Africa" });
// Circles (population)
svg.circle({
data: africa,
r: (d) => popradius.r(d.properties.poppct),
sort: "poppct",
fill: "#38896F",
stroke: "white"
});
// Nested circles (GDP)
svg.circle({
data: africa,
r: (d) => gdpradius.r(d.properties.gdppct),
transform: (d) =>
`translate(0, ${
popradius.r(d.properties.poppct) - gdpradius.r(d.properties.gdppct)
})`,
sort: "gdppct",
fill: "#893852",
stroke: "none"
});
// Legend
svg.legend.box({
pos: [100, 400],
rect_fill: "#38896F",
label: "Share of world\npopulation in this\ncountry"
});
svg.legend.box({
pos: [100, 440],
rect_fill: "#893852",
label: "Share of world\nGDP in this\ncountry"
});
// Legend
// Render
return svg.render();
}
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