ojs
ojs
ojs
Author
Nicolas Lambert
@neocarto
Front-end cartographer. Research Engineer in Geographic Information Science at CNRS & UAR RIATE. Author of Mad Maps (2019), Practical Handbook of Thematic Cartography (2016, 2020, 2025) and Cartographia (2025).
Comments (2)
Fati CHEN
Jan 3, 2023You can also do :
```observablehq
propertiesandgeom = geo.map(world, (d, i) => {
const [lon, lat] = d3.geoCentroid(world.features[i])
return {id: d.CNTR_ID,
name: d.CNTR_NAME,
lat,
lon,
geoArea: d3.geoArea(world.features[i])}
})
```
instead of accessors
Nicolas Lambert
Jan 3, 2023Thank you. It's much better this way. I add your code below.
© 2026 Observable, Inc.