Consolidate unique arcs.

[mbostock]

If an arc is only used once, it may be possible to merge it with an adjacent arc that is only also used once.

[mbostock]

In some ways the easiest way to fix this is to roundtrip through topo2geo and geo2topo again. In the case of the Merged Choropleth example you can reduce the 464K topology even further to 328K… or even 284K when quantized at 1e4, which seems sufficient for the display resolution!

topo2geo \
  < topo.json \
  tracts=tracts.json \
  counties=counties.json

geo2topo \
  tracts=tracts.json \
  counties=counties.json \
  | topoquantize 1e5 \
  > topo.json

[chabb]

Hello Mike!

Will it remove unused arcs too ?

Thanks !