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pythonplotpostgisspatialgeopandas

Geopandas polygon to line

I am new to geopandas and would like to plot only the outline of a polygon, similar to the function ST_Boundary() in PostGIS

I have a geodataframe states containing polygons for each state

states = counties.dissolve(by='STATEFP')

When I subset by one state, I am able to plot that state:

states.loc[states.index.isin(['06'])]['geometry']

I am only interested in the outline but it is not clear in the documentation how to convert a polygon to line geometry however. Is there a useful method in geopandas or another spatial library that might help in converting a polygon to a linestring?

enter image description here

Solution

  • You can get boundary as

    states.boundary

    Alternatively, if you want only exterior boundary you get it as

    states.exterior

    Those give you new GeoSeries with line geometry.