Dissolving polygon features with the sf package

Question

Dissolve is a common geoproccessing technique discussed as an sf approach here.

I\'m trying to replicate dissolve as it functions in ArcGIS. Consider counties by two gr

Answer 1

I am not too familiar with how ArcGIS defines a polygon, but the simple feature access (an ISO standard) specification of a polygon is a single ring with zero or more inner rings denoting holes. This means that under that specification, if you have the main land + a couple of islands, you don't have a single polygon. To represent these as a single feature, the corresponding geometry type is multipolygon. Meaning your answer is in nc_dissolve: it has two features.