Converting Polygon to MultiPolygon with Shapely?

Question

I'm writing code that loads data into a database. I have to do some validation/clean up of the data before inserting it. One of the requirements of the database is that this particular table only accepts multipolygons. (It's simpler to just make everything consistently a multipolygon than to try to handle the two different cases.)

I have the shape in the form of a Polygon object. I need to convert it to a multipolygon for insertion. (I would just use the SQL methods for this, but unfortunately, I'm using an ORM right now.)

How can I convert the Polygon object into a MultiPolygon object?

Answer 1

You can wrap the polygon in a list and pass that as an argument to the MultiPolygon constructor.

Demo:

from shapely.geometry.multipolygon import MultiPolygon
from shapely import wkt

p = wkt.loads(u'POLYGON((0 0,0 1,1 1,0 0))')
m = MultiPolygon([p])
print(m.wkt)
# prints 'MULTIPOLYGON (((0 0, 0 1, 1 1, 0 0)))'